This study explored stress & food preferences. 232 Flemish students completed a food frequency questionnaire and psychological tests to measure stress levels, during exam period, to determine effects of stress on food choices as part of a longitudinal study.
Results
Diet quality of the students was observed to deteriorate during the exam period in response to stress, with preferences for high fat and sugar foods increased. The study indicated that chronic stress alters food preferences to high fat and high sugar foods. However, the data was from food frequency questionnaires and self reported measures of stress levels. These methods are vulnerable to self reporting biases. Further research which monitors diet whilst taking serum samples of cortisol and other stress-related markers are required to explore these findings further.
Michels, N., Man, T., Vinck, B., & Verbeyst, L. (2020). Dietary changes and its psychosocial moderators during the university examination period. European journal of nutrition, 59(1), 273–286.
This study investigate bilingualism & cognition. The study was a meta analysis of studies. Inclusion criteria was studies investigating bilingualism in the elderly with relation to Alzheimer’s disease risk. 6 prospective cohort studies were selected and 8 retrospective studies were selected. Of the 14 studies, only 2 had a monolingual control group. 14 studies selected for analysis. Study indicated that bilingualism may be protective against memory decline in older adults.
Results:
Meta analysis indicates that one exception, the studies support the idea that bilingualism reduces risk of memory decline. . However, only a small sample of studies included, although selected studies generally of a good sample size (>500). Only two of the studies included participants with Alzheimer’s disease diagnosis. Moreover, only two studies had a control group. Further, two of the studies included only Hispanic subjects, which may have impacted results.
A notable limitation of the meta analysis is that it did not include any statistical analysis methods (i.e p value) and this is a significant limitation. Further large scale research is required to explore effects of bilingualism on cognition, and whether bilingualism may be protective against cognitive decline.
This study investigated bilingualism & cognition. Study included 28 older adult participants – 14 monolingual participants and 14 bilingual participants (who had been bilingual since before age 11). All participants were subjected to a fMRI and had no diagnosed mental health conditions.
Results indicated:
Bilingual participants performed better on tasks and had better working memory (p<0.01) and better connectivity (p=0.002), compared with the monolingual group (p=0.17)
Results observed for other types of memory were not significant
Study size was small. Further large scale warranted. Study did not specify regarding bilingualism, as to whether participants spoke more than 2 languages, or whether certain type and complexity of language afford greater protection (i.e romance languages, Germanic languages etc.). Further research merited to explore effects of bilingualism on other types of memory.
Grady, C. L., Luk, G., Craik, F. I., and Bialystok, E. (2015). Brain network activity in monolingual and bilingual older adults. Neuropsychologia 66, 170–181. doi: 10.1016/j.neuropsychologia.2014.10.042
In this study memory change over 6 years was assessed using a large scale sample (16, 638 elderly individuals born <1948) from Health and Retirement Study. Growth curve models were analysed with reference to memory recall of a 10 word list and levels of social integration (i.e with family, volunteering, marital status).
Results indicated:
Socialisation demonstrated as a predictor of slower memory decline (p<.01).
In individuals with vascular disease, socialisation observed to be protective buffer ( (p< 0.05)
Memory amongst least socialised deteriorated at twice the rate of other participants, with association greatest amongst those with <12 years of education (p<0.07)
The study indicates that socialisation and levels of education may be protective factors for memory decline. The study also suggests that socialisation may reduce risk for memory decline in individuals with vascular diseases. The study did not use a robust means of measuring memory capability, such as MMSE. Results for socialisation as a predictor of slower memory decline not statistically significant. However, socialisation in individuals with vascular disease as a protective factor was observed to be statistically significant. More research required as to the mechanisms of how socialisation reduces risk of memory decline in vascular disease. Findings for education as a protective factor were observed to be statistically significant. More research required into to what level of education is most protective against memory decline.
Ertel, K. A., Glymour, M. M., & Berkman, L. F. (2008). Effects of social integration on preserving memory function in a nationally representative US elderly population. American journal of public health, 98(7), 1215–1220.
This study explored fasting & cognitive performance. It identified that biological ageing is a process which is accelerated and exacerbated by excessive calories and a sedentary lifestyle. Further, these factors combined may increase the risk of developing neurodegenerative diseases. This systematic review explored the role of different types of IF (intermittent fasting) on cognitive function, with specific focus on BDNF (brain derived neurotrophic factor) as a marker. Reduction of levels of BDNF has been associated with cognitive decline and increased risk of Alzheimer’s disease. Moreover, reductions in BDNF may result in a reduction in synaptic plasticity, memory and learning.
The study accepted and appraised 82 papers. Key findings were:
IF modulated BDNF supporting synaptic maturation and function
Primary evidence demonstrates pro-cognitive and neuroprotective effects of IF and BDNF
Sex specific differences were observed in response to IF
IF was suggested to be supportive for brain health and sustaining cognitive performance into old age, although it was identified further research is required into this area
Seidler, K., & Barrow, M. (2021). Intermittent fasting and cognitive performance – Targeting BDNF as potential strategy to optimise brain health. Frontiers in neuroendocrinology, 65, 100971. Advance online publication. https://doi.org/10.1016/j.yfrne.2021.100971
A sample of 2,034 individuals (age >55) in Singapore were studied to explore the link between fish consumption and depression. The study was conducted as part of the Singapore Longitudinal Aging Studies (SLAS) project and results were adjusted for all other possible factors such as smoking, exercise, diabetes etc.
Individuals consuming fish three times per week were observed to report lower depressive symptoms, compared with those who did not consume fish.
Wu D., Feng L., Gao Q., Li J.L., Rajendran K.S., Wong J.C., Kua E.H., Ng T.P. Association between fish intake and depressive symptoms among community-living older Chinese adults in Singapore: A cross-sectional study. J. Nutr. Health Aging. 2016;20:404–407.exercise, diabetes etc
This study looked at the correlation between nutritional status of older adults and health. Correlation was observed between quality of nutritional status and depressive symptoms. Elderly individuals who perceived that they had poorer health, were also observed to be at higher risk of depression.
Jung, S. E., Bishop, A. J., Kim, M., Hermann, J., Kim, G., & Lawrence, J. (2017). Nutritional Status of Rural Older Adults Is Linked to Physical and Emotional Health. Journal of the Academy of Nutrition and Dietetics, 117(6)
MIND Diet vs Mediterranean Diet: Which Is Better for Brain Health?
If you search for the “best diet for brain health,” you’ll almost always come across the same two names: the Mediterranean diet and the MIND diet. In this article, we’ll explore the MIND Diet vs Mediterranean Diet debate to see how the two really compare. But after a decade of advances in nutritional neuroscience, perhaps that’s no longer the most useful question to ask.
When it comes to diets backed by the strongest evidence for brain or overall health, two consistently stand out: the Mediterranean diet and the MIND diet. Both have genuine scientific credibility. The Mediterranean diet has decades of research behind it, originally focused on cardiovascular health before later demonstrating important cognitive benefits, including a landmark trial showing improved cognitive performance in those following it [1]. The MIND diet was developed later, specifically to reduce cognitive decline by combining elements of the Mediterranean and DASH diets. One of the first large studies, involving almost 1,000 older adults, found that greater adherence was associated with significantly slower cognitive decline [2].
Both are excellent dietary patterns and are backed by a good and growing body of scientific evidence. If you are already eating this way, you are doing something positive for your brain.
But here is the question we can forget to ask.
What if the real opportunity is not choosing between these diets, but building on them?
This is not another article arguing that one diet is superior to the other. The more interesting question is whether either reflects everything we now know about protecting brain health and preventing dementia.
Neither diet was designed around the full body of evidence we have today. They were developed using the best available science at the time, and our understanding of dementia has advanced considerably since then. That does not make either diet wrong. It simply means they have provided an excellent foundation rather than the finished picture.
This is what we are interested in. Rather than forcing people into a specific dietary silo, we want to build on the various dietary strategies with newer evidence from nutritional neuroscience, biomarker research, and lifestyle medicine that has emerged over the past decade.
Before comparing the Mediterranean and MIND diets, it’s worth recognising that they have far more in common than they have differences. A comprehensive review published in 2019 found evidence supporting the Mediterranean, DASH, and MIND diets for better cognitive health [8], reflecting their shared emphasis on vegetables, whole grains, legumes, nuts, and minimally processed foods.
Mediterranean Diet vs MIND Diet: A Detailed Comparison
Mediterranean diet
MIND diet
Where it came from
A traditional dietary pattern associated with countries bordering the Mediterranean
A dietary pattern developed specifically for brain health by combining elements of the Mediterranean and DASH diets
Main focus
Overall health, particularly cardiovascular health and healthy ageing
Reducing the risk of cognitive decline and dementia
Foods emphasised
Vegetables, fruit, legumes, whole grains, nuts, olive oil and fish
Leafy green vegetables, other vegetables, berries, nuts, beans, whole grains, fish, poultry and olive oil
Foods limited
Red and processed meat, refined foods, added sugar and highly processed foods
Butter, cheese, red meat, fried foods, pastries and sweets
How prescriptive it is
Broad principles, with flexibility around quantities and frequency
More specific weekly targets for particular foods, especially leafy green vegetables and berries
Evidence base
Decades of research, strongest for cardiovascular health, with growing evidence for cognitive benefits
Strong observational evidence for brain health, with fewer intervention trials
Although the DASH diet is often included in these comparisons, it largely serves as one of the foundations of the MIND diet rather than a separate competitor. For that reason, the real comparison today is usually between the broader Mediterranean dietary pattern and the more brain-focused MIND diet.
Does the MIND Diet or Mediterranean Diet Offer Greater Brain Protection?
Based on the evidence, probably not.
One of the largest clinical trials to test the MIND diet followed participants for three years, comparing it with another healthy, calorie-reduced diet [4]. Both groups improved, but neither clearly outperformed the other. Rather than suggesting one dietary pattern is superior, the study reminds us that there are many ways to eat well and that healthy diets can have far more in common than they have differences.
The Mediterranean and MIND diets remain two of the best-researched dietary patterns for healthy ageing and brain health. Both are associated with better cognitive outcomes than a typical Western diet, and both provide an excellent foundation for most people.
The real opportunity in the MIND Diet vs Mediterranean Diet debate lies not in choosing between them, but in building on their shared strengths using what we have learned over the last decade.
Two people can follow exactly the same diet and have very different omega-3 levels, homocysteine levels, blood sugar control, and ultimately, different risks of cognitive decline.
Today, we can go beyond general dietary advice. Instead of simply recommending fish, we can assess omega-3 status. Instead of assuming a diet rich in leafy greens provides enough B vitamins, we can measure homocysteine. Instead of relying on diet alone to judge metabolic health, we can monitor HbA1c to identify early insulin resistance. The future of brain health is not choosing between dietary patterns. It is combining healthy eating with objective measures of what your brain actually needs.
A healthy diet does not guarantee optimal nutrition
Both the Mediterranean and MIND diets encourage leafy green vegetables, and with good reason. They are rich in folate, one of the B vitamins needed to help regulate homocysteine, a naturally occurring compound that becomes one of the clearest modifiable risk factors for brain shrinkage and cognitive decline when levels are elevated.
However, following these diets does not guarantee healthy homocysteine levels. Age, genetics, digestion, certain medications, and nutrient absorption all influence homocysteine, meaning two people eating the same diet can have very different results.
This highlights an important principle. Eating whole, unprocessed foods is an excellent and essential starting point, but it cannot tell you whether your nutritional status is optimal. In a randomised controlled trial, B vitamin supplementation slowed brain atrophy in people with elevated homocysteine [5], demonstrating that identifying and correcting nutritional deficiencies can make a measurable difference.
The story becomes even more interesting when we look at omega-3. Research suggests these nutrients work together rather than independently. In one study, B vitamins only slowed brain atrophy in people who already had adequate omega-3 status [6]. Another found the reverse: omega-3 supplementation only improved cognitive outcomes in people with low homocysteine, suggesting adequate B vitamin status is necessary for the brain to fully benefit from omega-3 [7] (read more overview of the interaction between omega-3, B vitamins, and brain health). Elevated homocysteine, which often reflects inadequate functional B vitamin status, is itself an established risk factor for cognitive decline.
The message is not that either diet is lacking. Rather, it is that nutrients interact in complex ways that no dietary pattern alone can predict. You cannot accurately know whether your omega-3 status or homocysteine levels are optimal simply by looking at what’s on your plate.
This is why you need a more personalised approach. Alongside encouraging healthy dietary patterns such as the Mediterranean or MIND diet, or even ketogenic or low-carb diets, we also believe in measuring key biomarkers, including homocysteine and omega-3 status, through the DRIfT® test. By combining dietary advice with specific biomarkers, or through tools like the Cognitive Function Test, it becomes possible to understand what your brain actually needs, rather than relying on assumptions.
Blood sugar matters too
Another thing to reflect on is that neither the Mediterranean nor the MIND diet was designed around blood sugar control as its primary goal. Compared with a typical Western diet, both are a major improvement. Their emphasis on vegetables, legumes, healthy fats, and minimally processed foods naturally supports steadier blood sugar than diets high in refined carbohydrates and ultra-processed foods.
However, neither diet asks an important question: how much carbohydrate is right for you?
Carbohydrate tolerance varies considerably between individuals. Someone who exercises regularly and is metabolically healthy may thrive on a Mediterranean-style pattern. Someone with insulin resistance or pre-diabetes may benefit from a lower-carbohydrate approach, even if the carbohydrates they eat come from healthy sources. Reflecting this, some clinicians are now using lower-carbohydrate and ketogenic diets therapeutically for selected neurological and mental health conditions.
The point is not that everyone should follow a lower-carbohydrate diet. It is that good metabolic health is consistently associated with better cognitive health, and no single dietary pattern is right for everyone. Healthy eating provides the foundation, but measuring markers such as HbA1c allows dietary advice to become far more personalised and useful for prevention.
Why diet alone is not enough for brain health?
Food is one of the most powerful tools we have to support brain health, but it is only one part of the picture.
Research consistently shows that regular physical activity, restorative sleep, social connection, and cognitive stimulation all influence the risk of cognitive decline. No dietary pattern can account for these factors on its own. This is why our COGNITION framework brings together the evidence across multiple areas of brain health, recognising that it is the combination of nutrition, lifestyle, and key health markers, rather than any single intervention, that has the greatest influence on long-term cognitive resilience.
Rather than searching for the single “best” diet, we believe it is more helpful to combine evidence-based nutrition with an understanding of your own biomarkers and lifestyle. This allows recommendations to be tailored to the individual, rather than the dietary label.
MIND diet vs Mediterranean diet: the question that matters more than which diet is best
Instead of asking whether the Mediterranean or MIND diet is better, perhaps the more useful question is:
How many proven brain health habits are part of your routine?
You might eat a Mediterranean diet yet still have elevated homocysteine, low omega-3 status, raised HbA1c, or poor sleep, all of which can influence long-term brain health. Diet is one important lever, but it is not the whole system.
To help people understand their own brain health more completely, we developed the Cognitive Function Test™ alongside the DRIfT® at-home blood test. Together, they assess key biomarkers, lifestyle, and established risk factors, helping identify where the greatest opportunities for improvement lie. They are not diagnostic tools, but they can provide a far clearer picture of your brain health than diet alone ever could.
The Mediterranean and MIND diets remain among the best-researched dietary patterns for healthy ageing and cognitive health. Both also share many principles with the DASH diet, reinforcing that healthy dietary patterns have far more in common than they have differences. But protecting your brain is about more than blindly following a dietary pattern, or worse, getting locked into dietary dogma. It is about understanding your own biology, identifying the risk factors you can change, and taking action before problems develop.
The future of brain health is not choosing the “perfect” diet. It is combining the best of nutritional science with personalised testing and evidence-based lifestyle changes, giving every person the opportunity to understand what their brain needs to stay healthy for decades to come.
Ready to understand your own brain health?
Healthy eating is a great place to start, but understanding your own risk factors allows you to make more informed decisions.
Barnes LL, Dhana K, Liu X, Carey VJ, Ventrelle J, Johnson K, Hollings CS, Bishop L, Laranjo N, Stubbs BJ, Reilly X, Agarwal P, Zhang S, Grodstein F, Tangney CC, Holland TM, Aggarwal NT, Arfanakis K, Morris MC, Sacks FM. Trial of the MIND Diet for Prevention of Cognitive Decline in Older Persons. New England Journal of Medicine. 2023;389:602-611. DOI: 10.1056/NEJMoa2302368
This article is intended for general information only and does not constitute medical advice. It is not a substitute for consultation with a qualified healthcare professional, and anyone with concerns about their cognitive health should seek individual guidance.
The evidence for the relationship between alcohol, coffee and tea and cognitive deficits/benefits has been confounding to date. This meta-analysis aimed to assess the current evidence available in terms of the dose–response relationship between alcohol, coffee or tea consumption and cognitive deficits. Interestingly, it concluded that, based on the studies and data reviewed, whilst excessive consumption of alcohol is known to have adverse health effects, light consumption of alcohol (<11 g/day) and of coffee (<2.8 cups/day) are associated with reduced risk of cognitive deficits. It also concludes that the cognitive benefits of green tea consumption increase with its daily consumption.
Alcohol, coffee and tea intake and the risk of cognitive deficits: a dose-response meta-analysis. Ran, L.S., Liu, W.H., Fang, Y.Y. et al. (2021) Epidemiology & Psychiatric Sciences. 30(e13).
The study investigated B Vitamins and prevention of cognitive decline. Elevation of homocysteine (Hcy) levels is well-established as a risk factor for Alzheimer’s and other types of dementia, yet controversy exists regarding whether B-vitamin-mediated reduction of homocysteine levels can benefit cognitive function.
The review concludes that “the evidence from this meta-analysis suggests that B vitamin supplementation was associated with a reduced rate of cognitive decline, especially in populations who received early intervention and long-term intervention. Pooled results suggest that folate in sufficiency, which already emerged in populations at the MCI stage, is a risk factor for dementia and cognitive decline, and higher intake of folate is associated with a decreased risk of incident dementia in non-dementia aged population. Considering demographic trends in many countries with rapidly aging populations and widespread insufficiency in dietary intake of B vitamins, the findings support the view that public health measures to improve B vitamin status should be targeted at people at risk of cognitive impairment, which would lower the health and societal burdens of dementia”.
Wang, Z., Zhu, W., Xing, Y., et al (2021) B vitamins and prevention of cognitive decline and incident dementia: a systematic review and meta-analysis, Nutrition Reviews
Vitamin D deficiency is more common in patients with schizophrenia. This is due to factors such as social isolation, lack of movement, smoking, spending less time outside, malnutrition, and disruption of vitamin D synthesis by antipsychotic drugs.
The study looked into the relationship between sunlight exposure and positive, negative, and cognitive symptoms. 52 patients were invited to take part and 40 completed the study.
Patients had their serum 25OHD levels measured in order to understand their current vitamin D level in the blood.
The following clinical assessment scales were used pre and post replacement of Vitamin D:
SANS – scale for the assessment of negative symptoms
SAPS – Scale for the Assessment of Positive Symptoms
WCST-CV- Wisconsin Card Sorting Test used to evaluate executive function
Vitamin D deficiency was found in 65.4% of the patients with vitamin D values below the normal limit.
Various levels of oral vitamin D was given once a week for eight weeks to the patients according to their initial levels. Vitamin D levels were measured again eight weeks after the initiation of the treatment. Additionally, patients whose serum vitamin D level could not reach > 30 ng/mL within the eight weeks were given additional doses until the optimal level was reached.
Results showed that the mean SANS score was statistically significantly lower after replacement of vitamin D and the total attention score was also significantly improved. The study therefore concluded that addressing vitamin D deficiency in schizophrenic patients (together with antipsychotic treatment) can improve the total attention span and positive and negative symptoms in schizophrenia.
This paper investigated iron deficiency and schizophrenia. Previous research finding that iron deficiency may alter dopaminergic transmission, this study was conducted to identify whether low blood iron levels could be related to severity of schizophrenia symptoms. This study was conducted on 121 patients during their first episode of schizophrenia disorder. Symptoms were measured using the positive and negative syndrome scale (PANSS), and iron deficiency was defined as a serum ferritin less than 20ng/ml. The study found patients with iron deficiency were significantly more likely to have more prominent negative symptoms, and patients with more negative symptoms had significantly lower serum ferritin (iron) levels than their counterparts. This study highlights a possibility for further investigation as to whether iron supplementation could be used as an intervention.
Kim SW, Stewart R, Park WY, Jhon M, Lee JY, Kim SY, Kim JM, Amminger P, Chung YC, Yoon JS. Latent iron deficiency as a marker of negative symptoms in patients with first-episode schizophrenia spectrum disorder. Nutrients. 2018 Nov;10(11):1707
This study investigated omega 3 and schizophrenia. Specifically, the study explored the effect of omega-3 supplementation in symptom severity in schizophrenic patients over a long period of time, as previous studies have had mixed findings when interventions lasted 10-12 weeks. A randomized placebo-controlled trial was conducted over 26 weeks to study whether omega-3 fatty acids would have an effect on symptom severity in first episode schizophrenic patients. 71 patients were assigned either a placebo of olive oil or 2.2g/day of omega-3 supplement. Severity of symptoms were measured using the positive and negative syndrome scale (PANNSS). A 50% improvement in symptom severity was recorded more frequently in the omega-3 group compared to the placebo group. Significant improvements were found in depressive symptoms, the level of functioning and clinical global impression when patients were supplemented. These findings suggest that a 6-month intervention of omega-3 supplementation may be able to decrease symptom severity in first episode schizophrenia patients.
Pawełczyk T, Grancow-Grabka M, Kotlicka-Antczak M, Trafalska E, Pawełczyk A. A randomized controlled study of the efficacy of six-month supplementation with concentrated fish oil rich in omega-3 polyunsaturated fatty acids in first episode schizophrenia. J Psychiatr Res. 2016 Feb;73:34-44.
This study explored antipsychotics, omega 3 and schizophrenia. The review compiled previous studies surrounding treatment of schizophrenia using omega-3 and looked at what pathways in the brain are impacted by an omega-3 supplementation. After compiling information on omega-3 and anti-psychotic drugs it was found that the drugs used to treat schizophrenia and omega-3 supplementation impact on dopamine and glutamate transmission, oxidative stress, inflammation, myelination, and neurotransmission pathways in a similar way. Through evaluation of multiple clinical studies on omega-3 supplementation it was concluded that omega-3 has been linked to improved symptoms in those experiencing a schizophrenic episode. This research suggests that omega-3 supplementation may be an important consideration in schizophrenia.
Shared Biological Pathways between Antipsychotics and Omega-3 Fatty Acids: A Key Feature for Schizophrenia Preventive Treatment? Int J Mol Sci. 2021 Jun 26;22(13):6881
This study investigated micronutrients in childhood psychosis. Childhood psychosis is difficult to address effectively with conventional pharmaceuticals, many of which have adverse long-term health consequences. In contrast, there are promising reports from several research groups of micronutrient treatment (vitamins, minerals, amino acids and essential fatty acids) of mood, anxiety and psychosis symptoms using a complex formula that appears to be safe and tolerable. The study reviews previous studies using this formula to support mental symptoms, and presents an 11-year-old boy with a 3-year history of mental illness whose parents chose to transition him from medication to micronutrients. Symptom severity was monitored in three clusters: anxiety, obsessive compulsive disorder and psychosis. Complete remission of psychosis occurred, and severity of anxiety and obsessional symptoms decreased significantly (p<0.001); the improvements are sustained at 4-year follow-up. A cost comparison revealed that micronutrient treatment was <1% of his inpatient mental healthcare. Additional research on broad-spectrum micronutrient treatment is warranted.
Efficacy and cost of micronutrient treatment of childhood psychosis. Rodway et al. (2012). British Medical Journal Case Reports, doi:10.1136/bcr-2012-007213
This study investigated omega 3 and anxiety. The study set out to determine if omega-3 fish oil supplementation could improve both anxiety levels and inflammation in a group of 68 medical students who didn’t have a diagnosis of an anxiety disorder but could be expected to be experiencing some level of anxiety as medical exams were coming up. The researchers measured anxiety levels, and took blood tests to measure markers of inflammation (known as proinflammatory cytokines). The subjects were given either a high dose fish oil (2g of the omega-3 EPA and 348mg of DHA) or a placebo capsule daily for 12 weeks. At this point, the measurements were taken again and these showed that those who had taken the fish oil had both lower levels of anxiety and lower levels of proinflammatory cytokines.
This 2007 New Zealand study investigated omega 3 concentrations and wellbeing. 2,416 people participating in the 1997 National Nutrition Survey. Researchers investigated if a relationship existed between the composition of fats in the blood and the mental and physical well-being.
They found that the higher the proportion of Omega 3 fats, the better the physical and mental wellbeing of the person. Specifically they measured EPA levels in the blood as well as the ratio of EPA to arachidonic acid (AA).
EPA is the fatty acid found in oily fish and fish oil supplements while AA is mostly found in meat and dairy products.
Crowe FL et al.,’Serum phospholipid n 3 long-chain polyunsaturated fatty acids and physical and mental health in a population-based survey of New Zealand adolescents and adults’. Am J Clin Nutr. 2007 Nov;86(5):1278-85
In a study of people with schizophrenia, measures were made of levels of essential fats in red blood cells. Essential fats were found to be lower in this sample, than in the sample group without schizophrenia. In addition, an association was observed between levels of essential fats and severity of schizophrenia symptoms experienced.
Sumiyoshi T et al. ‘Essential polyunsaturated fatty acids and social cognition in schizophrenia.’ Psychiatry Res. 2008 Jan 15;157(1-3):87-93.
This study investigated sleep deprivation & adolescence. Later parent-set bedtimes and correspondingly shorter sleep duration appears to be related to the development of depression in adolescence, a cross-sectional analysis showed. In the sample 24% of adolescents were shown to experience depression when going to sleep at midnight or later. In addition to depression, adolescents with later bedtimes also had a greater risk of having a 20% increased incidence of suicidal thoughts, compared with adolescents who went to bed before 10:00pm.
Gangwisch, J. E., Babiss, L. A., Malaspina, D., Turner, J. B., Zammit, G. K., & Posner, K. (2010). Earlier parental set bedtimes as a protective factor against depression and suicidal ideation. Sleep, 33(1), 97–106. https://doi.org/10.1093/sleep/33.1.97
This study assessed tryptophan & emotional processing. It explored whether tryptophan (TRP) induces cognitive changes opposite to the negative biases found in depression and characteristic of those induced by serotonergic antidepressants in healthy volunteers. Thirty eight healthy volunteers were randomised to receive 14 days double-blind intervention with TRP (1g for 3x a day) or placebo. On the final day, emotional processing was assessed using four tasks: facial expression recognition, emotion-potentiated startle, attentional probe and emotional categorisation and memory. The results showed that TRP increased the recognition of happy facial expressions and decreased the recognition of disgusted facial expressions in female, but not male, volunteers. TRP also reduced attentional vigilance towards negative words and decreased baseline startle responsivity in the females. It concludes that these findings provide evidence that TRP supplementation in women induces a positive bias in the processing of emotional material that is reminiscent of the actions of serotonergic antidepressants. This highlights a key role for serotonin in emotional processing and lends support to the use of TRP as a nutritional supplement in people with mild depression or for prevention in those at risk.
Murphy SE et al. ‘Tryptophan supplementation induces a positive bias in the processing of emotional material in healthy female volunteers’. Psychopharmacology (Berl). 2006 Jul;187(1):121-30. Epub 2006 May 4
This study investigated school children & healthy diets. A Canadian survey of 5,000 11 year olds and their families found that children who ate more fruits and vegetables and fewer calories from fat were 41% more likely to pass a literacy assessment. Furthermore, children with poor diet quality were observed to perform more poorly academically in school. Socioeconomic factors were taken into account when making the analysis.
Florence M D et al. ‘Diet quality and academic performance,’ J Sch Health. 2008 Apr;78(4):209-15
Research has demonstrated that healthy food boosts school performance. The Nutrition and Health survey in Taiwan Elementary School Children, 2001-2002, analysed the diets and school performance of 2,222 primary school children. The study shows that children with poorer overall school performance were more likely to eat sweets and fried foods and were less likely to eat foods rich in protein, vitamins and minerals.
Fu ML et al. ‘Association between Unhealthful Eating Patterns and Unfavorable Overall School Performance in Children’, J Am Diet Assoc. 2007;107:1935-1943
Research has investigated poor diet & mental health in teens. Three quarters of lifetime psychiatric disorders emerge in the teenage years or in early adulthood. In an Australian study involving 2054 teenagers, researchers found that during a 2 year period, the teenagers who improved the quality of their diets experienced improved mental health. In contrast, those whose diet quality deteriorated experienced a worsening of their mental health. A better quality diet was one that included fruit and vegetables as “core food groups” and included both 2 or more servings of fruit per day and 4 or more servings of vegetables, as well as general avoidance of processed foods including chips, fried foods, chocolate, sweets, and ice cream. A poorer quality diet was defined as one which was high in snack and processed foods. This study could have important implications for prevention of mental health disorders.
Jacka FN, Kremer PJ, Berk M, de Silva-Sanigorski AM, Moodie M, et al. (2011) A Prospective Study of Diet Quality and Mental Health in Adolescents. PLoS ONE 6(9): e24805.
Research has investigated schizophrenia & gluten free, low carb diets. The research relates the case of a schizophrenic woman whose symptoms improved when she was put on a low-carb, ketogenic diet. This highlights the possible link between coeliac disease and schizophrenia.
The review of several studies concludes that more research is needed to confirm the association between gluten intake and schizophrenia and whether dietary change can ameliorate schizophrenic symptoms. Health care providers could consider screening for coeliac disease and/or augment the medical regimen for patients with schizophrenia with a gluten free or low carb diet.
The study investigated fish oil & psychosis. Individuals at extremely high risk of developing psychosis appear less likely to develop psychotic disorders following a 12-week course of fish oil capsules containing long-chain omega-3 polyunsaturated fatty acids. Those taking the capsules also showed signs of reduced positive, negative and general symptoms of schizophrenia. Schizophrenic patients may have an underlying dysfunction in fatty acid metabolism and the potential effects of omega-3 polyunsaturated fatty acids on psychosis development may result from changes to cell membranes and interactions with neurotransmitter systems in the brain.
Research has investigated the link between diabetes & schizophrenia. This study looked at 99 patients with schizophrenia. Their 2 h post prandial plasma glucose was tested prior to medication and then again after 6 weeks on medication. The results were compared with a matched healthy control group. The study found a significant difference in baseline 2 h post-prandial blood suger between the control group and treatment group as well as significant increase in weight, fasting blood sugar and 2h post-prandial blood sugar from baseline to endpoint between the groups. It concluded that male patients with schizophrenia were liable to develop Diabetes Mellitus(DM) and antipsychotic treatment may lead to the development of DM in a significant 10% within 6 weeks.
Saddichha s et al ‘Diabetes and schizophrenia – effect of disease or drug? Results from a randomized, double-blind, controlled prospective study in first-episode schizophrenia’.Acta Psychiatr Scand. 2008 May;117(5):342-7. Epub 2008 Feb 26
Research has investigated food additives, hyperactivity and children. Lead researcher Professor Jim Stevenson says this study on food additives and hyperactive behaviour in children, carried out at Southampton University, shows that certain combinations of artificial food colours (tartrazine (E102), ponceau 4R (E124), sunset yellow (E110), carmoisine (E122), quinoline yellow (E104) and allura red AC (E129) as well as the commonly used preservative sodium benzoate (E211) are linked to increases in hyperactivity.
McCann D et al., Food additives and hyperactive behaviour in 3-year-old and 8/9-year-old children in the community: a randomised, double-blinded, placebo-controlled trial. Lancet. 2007 Sep 5
Research has suggested nutrition in infancy may be linked to adult earning power. The findings, published in The Lancet, were based on a three-decade study of Guatemalan males from birth. During the 1970s, some of the babies in the study were given a very nutritious food supplement, some a less nutritious one. When the researchers returned three decades later to see how the babies were faring, they found that men who had had the very nutritious supplement up to the age of three were earning nearly half as much more per hour than the other villagers. The women did not have similar wage differentials, possibly because they had less choice about where they worked. The researchers assert that these results are the first direct evidence of a clear link between early-life nutrition and adult wages, and that feeding babies well could drive economic growth.
Hoddinott J et al. ‘Effect of a nutrition intervention during early childhood on economic productivity in Guatemalan adults’ Lancet. 2008 Feb 2;371(9610):411-6
A total of 1092 subjects without dementia (667 women and 425 men; average age, 76 years) were followed for an average of 8 years. Their homocysteine levels were monitored and it was noted which of those went onto develop dementia and Alzheimer’s. The authors concluded that an increased level of homocysteine in the blood is a “strong, independent risk factor for the development of dementia and Alzheimer’s Disease”. There was a doubling of risk for Alzheimer’s with a homocysteine level greater than 14mmol/l.
Seshadri S et al,Plasma homocysteine as a risk factor for dementia and Alzheimer’s disease.N Engl J Med., 346(7):476-83, 2002
This study investigated homocysteine & schizophrenia. Forty-two schizophrenic patients with elevated plasma homocysteine levels were administered vitamins B6, B12 and folic acid or placebo for 3 months. Homocysteine levels declined with vitamin therapy compared with placebo in all patients. Clinical symptoms of schizophrenia as measured by the Positive and Negative Syndrome Scale declined significantly with the vitamin treatment compared with placebo. The researchers concluded that a subgroup of schizophrenic patients with elevated homocysteine might benefit from the simple addition of B vitamins.
Levine J et al, ‘Homocysteine-reducing strategies improve symptoms in chronic schizophrenic patients with hyperhomocysteinemia’, Biol Psychiatry., 60(3):265-9, 2006
Elevated Homocysteine and Schizophrenia (2007)
Elevated plasma levels of the amino acid homocysteine have been associated with schizophrenia, particularly in young male patients. Among other factors, low folic acid and vitamin B12 levels have been implicated in the increase in homocysteine.
In this study, 100 inpatients with chronic schizophrenia and 100 ‘normal controls’ had their blood levels of homocysteine, vitamin B12 and folic acid measured. While there was no difference in blood levels of folic acid or B12, the schizophrenia patients had higher homocysteine (15.42 v 11.54 µmol/l, p<0.001).
Both young and older females as well as younger males with schizophrenia had increased plasma homocysteine compared to controls. We therefore suggest that homocysteinemia is a general risk factor for schizophrenia
Haidemenos A, et al., Plasma homocysteine, folate and B12 in chronic schizophrenia, Prog Neuropsychopharmacol Biol Psychiatry. 2007 Aug 15;31(6):1289-96
This study examined the relationship between cognitive performance & fish intake. The study included 2,031 elderly Norwegians. The researchers report those eating at least 10 grams of fish a day performed significantly better in tests for cognitive performance, compared with people who ate less than 10 grams of fish and fish products. The best test scores occurred in those who consumed the most fish and fish products, which equates to 75 grams per day. Positive effects were observed to be more pronounced in unprocessed fish compared with processed fish intake. Interestingly, there was no significant difference between the consumption of lean or fatty fish, suggesting that the effects were due to something other than omega-3 fatty acids. However, further research is required to explore this area further.
This study investigated omega 3 & cognitive decline. This was a prospective study of 2,000 people aged 50 to 65 years old. Results indicated that risk of global cognitive decline increased with elevated palmitic acid in both fractions and with high arachidonic acid and low linoleic acid in cholesteryl esters. Higher n-3 HUFAs reduced the risk of decline in verbal fluency, particularly in hypertensive and dyslipidemic subjects.
M A Beydoun, ‘Plasma n-3 fatty acids and the risk of cognitive decline in older adults: the Atherosclerosis Risk in Communities Study’, Am J Clin Nutr., vol 85(4):1103-1111, 2007
A total of 4,500 elderly people were involved in a 5-11 year study of the effects of blood calcium levels on cognitive decline. Cognitive function was measured using the Mini-Mental State Examination (MMSE) and other measures of attention and memory. Higher levels of blood calcium (but still within the normal levels) was associated with worse cognitive function at the beginning of the study. They were also associated with a faster rate of decline in cognitive function during follow-up.
Schram MT et al, ‘Serum calcium and cognitive function in old age’, J Am Geriatr Soc. 2007 Nov;55(11):1786-92
This study explored folic acid & cognition. In this study, over 1000 elderly people who were not having problems with their memory or mental function underwent a battery of tests. These tests showed that those with the highest blood levels of folic acid scored the best on tests of their ‘global cognitive function’ and ‘psychomotor speed’ – essentially their mental agility. These findings require further investigations to determine their relevance in subjects with dementia.
de Lau LM et al. ‘Plasma folate concentration and cognitive performance: Rotterdam Scan Study,’ Am J Clin Nutr. 2007 Sep;86(3):728-34
This study investigated folic acid & memory. Absent-mindedness in the over-50s is significantly improved when people take folic acid supplements, according to this large study. Short-term memory, mental agility and verbal fluency tests were all better among people who took the supplement for three years, compared with a group given a placebo.
J Durga et al, ‘Effect of 3-year folic acid supplementation on cognitive function in older adults in the FACIT trial: a randomised, double blind, controlled trial ‘, The Lancet; 369:208-216, 2007
This study investigated fish oil & cognitive decline. 210 men aged 70 to 89 years old were followed for 5 years. There was a significant association between intake of fish oil (EPA and DHA) from diet and rate of cognitive decline, with those taking in the most fish oil from oily fish showing the least decline. The measure of decline used the Mini-Mental State Exam (MMSE) which includes questions on orientation to time and place, registration, attention and calculation, recall, language, and visual construction.
B M van Gelder et al, ‘Fish consumption, n-3 fatty acids, and subsequent 5-y cognitive decline in elderly men: the Zutphen Elderly Study’ American Journal of Clinical Nutrition, vol (85)4; 1142-1147, 2007
This study investigated the microbiome, anxiety & depression. It is understood that there is constant communication between the gut and the brain (the gut-brain axis). In this study, mice were fed a strain of probiotic (gut bacteria) or placebo. The mice who received the probiotics showed significantly fewer stress, anxiety and depression-related behaviours than the unsupplemented mice (controls). Not only was their behaviour different, but their levels of stress hormones were lower too. The researchers also observed altered GABA activity in the brains of the supplemented mice, suggesting a direct effect on brain chemistry.
Bravo JA, Forsythe P, Chew MV, Escaravage E, Savignac HM, Dinan TG, Bienenstock J, Cryan JF. (2011) Ingestion of Lactobacillus strain regulates emotional behavior and central GABA receptor expression in a mouse via the vagus nerve. Proc Natl Acad Sci U S A. Aug 29. [Epub ahead of print]
This study examined the relationship between consumption of breakfast & cognition. Subjects included 7,343 10th grade students from Oslo, Norway who completed a questionnaire assessing these variables. The main finding from this study was that eating breakfast regularly is associated with less mental distress and improved academic performance. The association was stronger for boys, than girls.
Lien, L., ‘Is breakfast consumption related to mental distress and academic performance in adolescents?’, Public Health Nutrition, 10(4), 422-428, 2006 July
This study investigated depression & processed foods. Eating a diet high in processed food increases the risk of depression, according to a recent study. Data on diet among 3,500 middle-aged civil servants was compared with self reported depression five years later. Those in the ‘whole food’ (plenty of vegetables, fruit and fish) group had a lower risk of depression compared with those who had a high consumption of processed foods, the University College London team found. The team said the study was the first to look at the UK diet and depression.
Akbaraly, T. N., Brunner, E. J., Ferrie, J. E., Marmot, M. G., Kivimaki, M., & Singh-Manoux, A. (2009). Dietary pattern and depressive symptoms in middle age. The British journal of psychiatry : the journal of mental science, 195(5), 408–413. https://doi.org/10.1192/bjp.bp.108.058925
This study investigated fish oil & depression. Moderate dose of Omega-3 fish oil was observed to improve mood in depressed elderly. In this small randomised controlled trial, a group of elderly people with mild to moderate depression were given either a fish oil capsule (with 300mg of the omega-3 essential fats EPA and DHA) or a placebo for six months. The researchers found that intervention with the fish oil was clinically effective.
Tajalizadekhoob, Y., Sharifi, F., Fakhrzadeh, H., Mirarefin, M., Ghaderpanahi, M., Badamchizade, Z., & Azimipour, S. (2011). The effect of low-dose omega 3 fatty acids on the treatment of mild to moderate depression in the elderly: a double-blind, randomized, placebo-controlled study. European archives of psychiatry and clinical neuroscience, 261(8), 539–549. https://doi.org/10.1007/s00406-011-0191-9
This study investigated iron & depression. Two hundred women who were not anaemic had their mood and blood iron levels measured. The iron levels in the women who were rated as depressed (67) were significantly lower than in the healthy controls (125).
M Vahdat Shariatpanaahi et al., ‘The relationship between depression and serum ferritin level’, European Journal of Clinical Nutrition, 61; 532-535, 2007
This study investigated vitamins, minerals & mood. 225 hospitalised acutely ill elderly people were either given a normal hospital diet plus multivitamin and mineral supplements (providing 100 per cent of the Reference Nutrient Intakes for a healthy older person for vitamins and minerals), or a normal hospital diet plus a placebo for six weeks. Measures of mood and mental agility were taken at the start, at six weeks and six months later. There were significant differences in symptoms of depression scores in the supplement group compared with the placebo group at 6 months. This effect was seen in all patient groups including those with no symptoms of depression, mild depression and those with severe depression.
Gariballa S and Forster S, ‘Effects of dietary supplements on depressive symptoms in older patients: A randomised double-blind placebo-controlled trial.’ Clin Nutr. 2007 Jul 25
This study investigated omega 3, depression & children. Antidepressant medication is not recommended for children due to concerns over adverse side effects. In this pilot study of omega-3 fatty acids in children with major depression, 28 children aged between 6 and 12 years old were assessed using the Children’s Depression Rating Scale (CDRS), Children’s Depression Inventory (CDI), and Clinical Global Impression (CGI). Children were given either omega-3 fatty acids or sugar pills (placebo) for up to 16 weeks. Analysis of the results showed highly significant benefits of omega-3 versus placebo, on symptoms measured by the CDRS, CDI, and CGI rating scales.
H Nemets et al ‘Omega-3 Treatment of Childhood Depression: A Controlled, Double-Blind Pilot Study’. Am J Psychiatry 2006; 163:1098–1100
This review explored folate & depression. A review of all randomized controlled trials that compared treatment with folic acid or 5′-methyltetrahydrofolic acid to an alternative treatment, for patients with depression. Three randomized trials (247 participants) were included. Two studies assessed the use of folate in addition to other treatment, and found that adding folate reduced Hamilton Depression Rating Scale (HDRS) scores on average by a further 2.65 points [95% confidence interval (CI) 0.38-4.93]. The remaining study found no significant difference when folate alone was compared with trazodone. The limited available evidence suggests folate may have a potential role as a supplement to for depression. It is currently unclear if this is the case both for people with normal folate levels, and for those with folate deficiency.
M J Taylor, ‘Folate for depressive disorders: systematic review and meta-analysis of randomized controlled trials.’, J Psychopharmacol., 18(2):251-6, 2004
This study investigated chromium & depression. In a placebo-controlled, double-blind pilot study of 15 subjects, chromium picolinate was observed to improved the moods of 70% of those taking chromium compared with 0% on placebo. Two hypothesised mechanisms of actions with relation to the observed results include 5HT2A downregulation and increased insulin sensitivity. However, due to the small sample number further studies are warranted including a greater number of participants to explore this area further.
Davidson et al., ’Effectiveness of chromium in atypical depression: a placebo-controlled trial’, Biol Psychiatry, 53(3):261-4, 2003
This study explored omega 3 & breast milk. The Omega-3 fatty acid DHA found in oily fish has a role in visual development in infants. In a study of 39 breast-fed infants, it was found that the mothers who consumed the most fish had the highest levels of DHA in their breast milk. The babies who were fed on breast milk with the highest levels of DHA had the best visual development. This may have implications for dyslexia, but further research is required to substantiate further.
M H Jørgensen et al., ‘Is there a relation between docosahexaenoic acid concentration in mothers’ milk and visual development in term infants?’, J Pediatr Gastroenterol Nutr.32(3):293-6, 2001
This study investigated Vitamin D & Parkinson’s. Early, untreated Parkinson’s disease is linked to a deficiency in vitamin D, more so than in those without the disease. In this 5-year study of 157 participants, the majority had some level of deficiency at the start of the trial. However, at the end of the study, vitamin D levels had increased suggesting that levels do not necessarily decline with disease progression.
Dutch researchers compared vitamin D levels with mood in a study of 1,282 elderly people. They found that vitamin D levels were 14% lower in those with depression. Measures of parathyroid hormone showed that this hormone was 5-33% higher in elderly individuals with depression. Depression severity was also observed to be associated with serum vitamin D levels and parathyroid hormone levels.
Vitamin D is known as the ‘sunshine vitamin’ because the primary source of it is from the action of the sun on your skin.
Hoogendijk W J G et al. ‘Depression Is Associated With Decreased 25-Hydroxyvitamin D and Increased Parathyroid Hormone Levels in Older Adults.’ Arch Gen Psychiatry. 2008;65(5):508-512
This study investigated learning and memory in school children. In two parallel studies (randomised, double-blind), a total of 780 school aged Indonesian and Australian children were given either a combination of vitamins and minerals, a supplement of omega-3 essential fats EPA and DHA, or the vitamins and minerals with the omega-3 fats, or a placebo on 6 days a week for 12 months. At the start of the trial, the children were tested for blood levels of all of these nutrients, all of which significantly improved when they were retested after 12 months. The Australian children on the vitamins and minerals had significant improvement in tests of verbal learning and memory as did the Indonesian girls.
Osendarp SJ et al. ‘Effect of a 12-mo micronutrient intervention on learning and memory in well-nourished and marginally nourished school-aged children: 2 parallel, randomized, placebo-controlled studies in Australia and Indonesia’ Am J Clin Nutr. 2007 Oct;86(4):1082-93
This study looked at the impact of diet on behaviour. A review of five well-designed studies found that elimination diets reduced hyperactivity-related symptoms. The picture was of children potentially responding to a wide range of food items although the pattern was individual to the child. Supplementation with essential fatty acids decreased violence although there was no evidence of an influence on hyperactivity. Three well-designed studies have reported that vitamin/mineral supplementation reduced anti-social behaviour. There are also findings of an association between a tendency to poor blood sugar balance and aggression. Many responses to diet were idiosyncratic and involved a wide range of foods interacting with individual differences in physiology.
D Benton, ‘The impact of diet on anti-social, violent and criminal behaviour’, Neurosci Biobehav Rev.;31(5):752-74, 2007
This study explored the impact of folic acid on children. Dutch researchers report that the children of mothers who took folic acid supplements during pregnancy were better at internalising and externalising problems, compared to the children of mothers who did not take supplements. The researchers also suggested that supplementation during pregnancy may reduce incidence of mental health conditions in children, although this area requires further research.
Roza, S. J., van Batenburg-Eddes, T., Steegers, E. A., Jaddoe, V. W., Mackenbach, J. P., Hofman, A., Verhulst, F. C., & Tiemeier, H. (2010). Maternal folic acid supplement use in early pregnancy and child behavioural problems: The Generation R Study. The British journal of nutrition, 103(3), 445–452.
This study explored behaviour, cognition and children. In this preliminary study, researchers investigated the relationship between lead, zinc and iron levels and cognition and behaviour in school children within a lower income population. Forty-two children, aged between 3 and 5 participated in the study. Nutrient status was assessed using blood samples. Behaviour was assessed by teacher’s using the California Preschool Social Competency Scale, Howes’ Sociability subscale, and the Preschool Behaviour Questionnaire and cognition was tested using the McCarthy Scales of Children’s Abilities.
The findings from this study are preliminary and should be interpreted with caution, particularly as the sample size was small. However, associations were seen between low zinc levels and higher anxiety as well as lower verbal scores. High lead levels were associated with lower teacher ratings of sociability and classroom social competence in girls. Children with both low zinc and low iron had the lowers verbal scores, although this result did not reach significance. The study does, however, contribute to the literature showing that levels of essential vitamins and minerals and toxic metals can impact children’s cognition and behaviour.
Hubbs-Tait, L. et al., ‘Zinc, Iron, and Lead: Relations to Head Start Children’s Cognitive Scores and Teachers’ Ratings of Behavior’, Journal of the American Dietetic Association, 107(1), 128-133, January 2007
This study investigated omega 3, depression and bipolar. A meta-analysis (review of studies to date) by scientists in Taiwan suggests that omega-3 fatty acids have significant antidepressant effects in patients with depression and bipolar disorder. The researchers interpret the results cautiously, however, and recommend large-scale, well-controlled trials are conducted to determine who would benefit most from fish oils, what level of dose is required and specific composition of fish oils that should be used .
Lin PY and Su KP. ‘A meta-analytic review of double-blind, placebo-controlled trials of antidepressant efficacy of omega-3 fatty acids’ J Clin Psychiatry, 2007 Jul;68(7):1056-61
This paper investigated omega 3 & bipolar. In a 12-week, double-blind study individuals with bipolar depression received either 1 g of EPA a day, 2 g/day or placebo, alongside their existing medication. Effectiveness of this treatment was assessed using the Hamilton Rating Scale for Depression (HRSD), as well as the Young Mania Rating Scale and Clinical Global Impression Scale (CGI). Significant improvement was seen with the EPA compared with placebo in the HRSD (P=0.04) and the CGI (P=0.004) scores. There was no apparent benefit of 2 g over 1 g dose. Both doses were well tolerated.
S Frangou et al., ‘Efficacy of ethyl-eicosapentaenoic acid in bipolar depression: randomised double-blind placebo-controlled study’, Br J Psychiatry, 188:46-50, 2006
This study investigated beta carotene & memory. In an 18 year study of over four thousand middle-aged to elderly men, those who took 50mg of beta-carotene on alternate days scored much better in tests of general cognition and verbal memory than those who took a placebo.
Grodstein F et al., ‘A Randomized Trial of Beta Carotene Supplementation and Cognitive Function in Men: The Physicians’ Health Study II’. Arch Intern Med. 2007 Nov 12;167(20):2184-90.
This study investigated breast milk and brain health. In a study of 17,046 babies, followed for 6.5 years, those that were breastfed scored better on all measures of intelligence and academic skills of reading and writing than those who were not.
Kramer M S et al., Breastfeeding and Child Cognitive Development New Evidence From a Large Randomized Trial, Arch Gen Psychiatry. 2008;65(5):578-584
The study investigated omega 3 & depression. In a small study, specific areas of the brains of deceased patients who had suffered from Major Depressive Disorder (MDD) were compared with the brains of ‘age-matched normal controls’. The omega-3 fatty acid DHA was significantly different (-22%) in the brains of the individuals with depression, compared to the normal controls. Interestingly, there was a greater difference when comparing the female brains than when comparing the male brains. This study suggests that DHA deficiency may be a contributory factor in depressive disorders, particularly in females.
McNamara RK et al., Selective deficits in the omega-3 fatty acid docosahexaenoic acid in the postmortem orbitofrontal cortex of patients with major depressive disorder. Biol Psychiatry. 2007 Jul 1;62(1):17-24.
This study investigated fish & memory. In this study, 260 healthy people were assessed for their level of fish consumption, their cognitive function and also underwent an MRI to assess their brain volume twice with a 10-year interval. It was found that those who ate baked or grilled fish on a weekly basis had better cognitive function and better levels of grey matter in their brain.
Raji, C. A., Erickson, K. I., Lopez, O. L., Kuller, L. H., Gach, H. M., Thompson, P. M., Riverol, M., & Becker, J. T. (2014). Regular fish consumption and age-related brain gray matter loss. American journal of preventive medicine, 47(4), 444–451. https://doi.org/10.1016/j.amepre.2014.05.037
The study investigated homocysteine & brain atrophy. Through MRI examination of the brains of 36 healthy elderly individuals, results indicated that there appears to be an association between brain atrophy (shrinking) and higher levels of homocysteine. However, due to the small sample size further research is required to substantiate these findings further.
P S Sachdev et al., ‘Relationship between plasma homocysteine levels and brain atrophy in healthy elderly individuals’, Neurology, 58(10):1539-41, 2002
This research investigated omega 3 & cognitive performance. Dutch researchers used data from a trial involving 404 men and women (average age 60 at the start). The researchers report that higher blood levels of omega-3 fatty acids was associated with a 60 % lower decline in mental processing speed over three years.
Dullemeijer C et al., ‘n 3 Fatty acid proportions in plasma and cognitive performance in older adults’, Am J Clin Nutr. 2007 Nov;86(5):1479-85
This study explored omega 3 & pregnancy. Canadian researchers found that higher levels of the omega-3 DHA in the umbilical cord at birth was associated with better vision at 6 months of age and better performance in mental and coordination tests at 11 months in a study of 109 babies. Higher levels of DHA were also associated with a lower rate of pre-term delivery. The same benefits to the baby were not seen from DHA in breast milk, leading the researchers to assert that DHA is particularly important in the 3rd trimester as the brain goes through a ‘growth spurt’. DHA is found in oily fish and seed oils.
J L Jacobson et al. ‘Beneficial effects of a polyunsaturated fatty acid on infant development: evidence from the inuit of arctic Quebec.’ J Pediatr. 2008 Mar;152(3):356-64
This study investigated cognitive activity & lifespan. In this study, researchers wanted to compare cognitive and physical activity taken over a person’s lifetime with the amount of a protein called ß-amyloid which had been deposited in their brain. ß-amyloid is the protein which is the key marker of Alzheimer’s disease. In total they studied 86 people (65 healthy older individuals with an average age of 76 years, 10 Alzheimer’s patients with an average age of 75 years, and 11 young healthy people with an average age of 25 years).
The researchers found a significant association between lower levels of ß-amyloid and greater participation in cognitively stimulating activities across the lifespan, particularly when undertaken in early and middle life. The researchers’ findings suggest that keeping your brain active throughout life may prevent or slow deposition of ß-amyloid, perhaps influencing the onset and progression of Alzheimer’s disease.
Landau SM, Marks SM, Mormino EC, Rabinovici GD, Oh H, O’Neil JP, Wilson RS, Jagust WJ. (2012) Association of Lifetime Cognitive Engagement and Low ß-Amyloid Deposition.Arch Neurol. Jan 23. [Epub ahead of print]
This study investigated folate, B12 & cognitive impairment. A high folic acid and B12 intake in the elderly may be protective against age-related memory decline. However, those with a high folic acid intake, from fortified food or supplements, but a low B-12 status have more memory decline and hence a greater risk for dementia. They are also at greater risk of anaemia. This research found that 4% of the elderly in the USA have high folate and low B12 status.
In seniors with low vitamin B-12 status, high serum folate was associated with anemia and cognitive impairment. When vitamin B-12 status was normal, however, high serum folate was associated with protection against cognitive impairment.
M S Morris, ‘Folate and vitamin B-12 status in relation to anemia, macrocytosis, and cognitive impairment in older Americans in the age of folic acid fortification’, Am J Clin Nutr.85(1):193-200, 2007
This study investigated gluten, dairy & autism. The study reviewed seven trials of gluten/casein (cereal and milk protein) elimination diets in children with autism spectrum disorders. All trials reported some success in reducing symptoms of autism. However, the authors consider that design flaws in the studies weaken confidence in the findings and they make recommendations for future trials.
GW Christison, K Ivany, ‘Elimination diets in autism spectrum disorders: any wheat amidst the chaff?’, J Dev Behav Pediatr, vol 27(2 Suppl):S162-71, 2006.
This study evaluated the association between plasma homocysteine levels and cognition. The presence of mild cognitive impairment (MCI) in 1215 elderly subjects (aged 60-85years) from Korea was assessed. Individuals with MCI may be at an increased risk for developing dementia, including Alzheimer’s disease. Homocysteine levels, in addition to folate and vitamin B12 levels were measured in blood samples. The presence of MCI was assessed by an independent physician using Mayo clinic criteria which included: 1) memory complaint, preferably corroborated by an informant; 2) objective memory impairment for age; 3) largely preserved general cognition; 4) essentially normal activities of daily living; and 5) no dementia.
The results also showed that high homocysteine was associated with low blood folate or vitamin B12 levels suggesting that supplementation of these nutrients may be helpful in reducing elevated homocysteine levels.
The results found a strong association between increased plasma homocysteine levels and risk of MCI. The association appeared to be independent of other well-known risk factors for cognitive decline such as age, sex, education, smoking, marital status, and serum vitamin levels which suggests that hyperhomocysteinemia may be an independent risk factor for MCI in elderly Korean subjects.
Kim, J. et al., ‘Plasma Homocysteine Is Associated with the Risk of Mild Cognitive Impairment in an Elderly Korean Population’, The Journal of Nutrition, 137 (9), 2093-2098, September 2007
This study investigated B12 & cognition. This study compared markers of vitamin B12 deficiency with various measures of brain shrinkage (MRI scans) and function (neuropsychological test results) over a 5 year period. Results indicated that Methylmalonate, a specific marker of B12 deficiency, may affect cognition by reducing total brain volume. However, the effect of homocysteine (nonspecific to vitamin B12 deficiency) on cognitive performance may be mediated through increased white matter hyperintensity and cerebral infarcts.
Tangney CC, Aggarwal NT, Li H, Wilson RS, DeCarli C, Evans DA, Morris MC (2011) Vitamin B12, cognition, and brain MRI measures – A cross-sectional examination. Neurology 77:1276-1282
This study investigated vitamin C & cognition. A new Danish animal study suggests that vitamin C deficiency in the first weeks and months of life may impair the development of neurones in the brain and decrease spatial memory. Guinea pigs subjected to moderate vitamin C deficiency were found to have 30 per cent fewer hippocampal neurons and poorer spatial memory, compared with guinea pigs given a normal diet. The Danish researchers used guinea pigs because, like humans, the animals cannot synthesise vitamin C, and can only obtain it via the diet.
“Although a direct extrapolation of this new phenomenon to humans is not currently possible, we found that the relatively high prevalence of vitamin C deficiency in humans, including infants and toddlers, warrants future clinical studies to clarify whether a similar link to brain development exists in humans, …….. We speculate that the lack of vitamin C supplementation in high-risk individuals, such as pregnant women and newborns with poor vitamin C status, could be detrimental to normal brain development and lead to neurologic disabilities later in life.” wrote the researchers, led by Jens Lykkesfeldt, professor of pharmacology and toxicology at the University of Copenhagen.
This study investigated homocysteine & brain shrinkage. UCLA School of Medicine researchers inlcuding a sample of 732 elderly people subjected to MRI brain scans, found that those with raised homocysteine levels have greater brain shrinkage regardless of age and diagnosis. Among those with cognitive impairment, the greater the homocysteine level the greater was the brain atrophy. The authors state ‘ Vitamin B supplements such as folate may help prevent homocysteine-related atrophy in Alzheimer’s disease by possibly reducing homocysteine levels.’
Rajagopalan, P., Hua, X., Toga, A. W., Jack, C. R., Jr, Weiner, M. W., & Thompson, P. M. (2011). Homocysteine effects on brain volumes mapped in 732 elderly individuals. Neuroreport, 22(8), 391–395. https://doi.org/10.1097/WNR.0b013e328346bf85
This study examined vitamin D & cognition. Vitamin D status, cognitive performance, mood, and physical performance in older adults was assessed. 58% of the participants were found to have abnormally low vitamin D levels. Vitamin D deficiency was associated with presence of a mood disorder and with worse performance on 2 measures of mood and cognitive performance.
C H Wilkins et al., ‘Vitamin D deficiency is associated with low mood and worse cognitive performance in older adults’, J Geriatr Psychiatry, 14(12):1032-40, 2006
This study investigated immunity & autism. The authors review research linking autism spectrum disorders with various abnormal immune responses during development. Interactions between the immune system and nervous system begin early in embryonic development, with normal nervous system development dependent on a normal balanced immune response. Several immune system disturbances have been linked to autism. Digestive system disturbances have been found in a significant proportion of autistic patients and the authors review studies linking gluten and casein (cereal and milk proteins) to autism.
P Ashwood, S Wills, J Van de Water, ‘The immune response in autism: a new frontier for autism research’, J Leukoc Biol, vol 80(1):1-15, 2006.
This study explored autism statistics. A new, comprehensive survey of adults in the UK reports that approximately one in a hundred have autism, defined on a tight set of criteria. These figures are similar to estimates in children. Results further suggested the weighted prevalence of autism in adults was estimated to be 9.8 per 1000 (95% confidence interval, 3.0-16.5). Prevalence was not related to the respondent’s age. Rates were higher in men, those without educational qualifications, and those living in rented social (government-financed) housing. There was no evidence of increased use of services for mental health problems.
This study focused on immunity & autism. The authors considered how immune reactions to food proteins may relate to immune reactions against the body’s own brain cells in autistic patients. The immune reactions of 50 autistic patients to a range of food proteins were compared to the immune reactions to brain proteins. 50 non-autistic patients were used as controls. The study found immune antibodies in autistic patients which reacted to both gliadin (a gluten protein from cereals) and to brain proteins, suggesting a possible autoimmune basis for autism.
A Vojdani et al., ‘Immune response to dietary proteins, gliadin and cerebellar peptides in children with autism.’, Nutr Neurosci, vol 7(3):151-61, 2004
This study explored autism & digestion. In the study, the role of immune sensitivity to dietary proteins in young children with autism was investigated. Of 109 children with autism, 75 had symptoms of digestive disturbance and 34 did not. 15 had known food hypersensitivities. Controls were 19 non-autistic children. Immune system markers of hypersensitivity to three milk proteins, gliadin (a gluten protein) and soy were measured. Children with autism showed a significant immune response to lactoglobulin (a milk protein) and those with digestive symptoms also showed a significant immune response to gliadin, compared to controls. However, no unusual response to casein (a milk protein) or soy was observed.
H Jyonouchi et al., ‘Evaluation of an association between gastrointestinal symptoms and cytokine production against common dietary proteins in children with autism spectrum disorders.’, J Pediatr, vol 146(5):605-10, 2005
This study investigated the mediterranean diet & depression. In a study of over 10,000 healthy Spanish participants – those who followed a Mediterranean diet most closely had a greater than 30% reduction in the risk of depression.
The specific mechanisms which help to prevent the occurrence of depression are not well known, however, the authors suggest that the role of the overall dietary pattern may be more important than the effect of single components. It is plausible that the synergistic combination of a sufficient provision of omega-three fatty acids together with other natural unsaturated fatty acids, antioxidants from olive oil and nuts, flavonoids and other phytochemicals from fruit and vegetables and increase levels of folate and other B vitamins in the overall Mediterranean diet may exert a fair degree of protection against depression.
The study investigated homocysteine & eating disorders. Plasma homocysteine levels were found to be elevated in women and older female adolescents (but not in young female adolescents) with eating disorders. These findings were not observed to be related to deficiencies in vitamin B12 or folic acid.
Levine J et al,Plasma homocysteine levels in female patients with eating disorders Int J Eat Disord., 40(3):277-84, 2007
This study investigated risk factors for Alzheimer’s. This study looked at the evidence regarding seven modifiable risk factors for Alzheimer’s. They calculated that about half of the 33 million cases worldwide could be prevented (that’s 17 million) and calculated that if these risk factors were to be modified to only a ‘relatively modest degree’, specifically by 10-25% as many as 1 – 3 million cases of the current 33 million worldwide could have been prevented.
The risk factors they considered were diabetes, midlife high blood pressure (hypertension), midlife obesity, smoking, depression, cognitive inactivity or low educational attainment, and physical inactivity. A major shortcoming of this report is that they didn’t consider dietary and lifestyle factors such as increasing B vitamins / reducing homocysteine, increasing essential fats and vitamin D, adopting a Mediterranean diet.
Barnes, D. E., & Yaffe, K. (2011). The projected effect of risk factor reduction on Alzheimer’s disease prevalence. The Lancet. Neurology, 10(9), 819–828. https://doi.org/10.1016/S1474-4422(11)70072-2
This study investigated omegas 3, 6 & DCD. DCD (Developmental Coordination Disorder) is associated with core deficits in motor function as well as difficulties in learning, behaviour and psychosocial adjustment that persist into adulthood. In a randomised, controlled trial, 117 children with DCD aged 5-12 years were given omega-3 and omega-6 fatty acid supplements or placebo for 3 months. At this point all children received the omega-3 and omega-6 supplements for a further 3 months. While there appeared to be no effect on motor skills, there were significant improvements in reading, spelling and behaviour in the children on the essential fat supplements compared with those on placebo and then similar improvements were seen for the placebo group once they started supplementation.
A J Richardson & P Montgomery, ‘The Oxford-Durham study: a randomized, controlled trial of dietary supplementation with fatty acids in children with developmental coordination disorder ‘, Pediatrics, 115(5):1360-6, 2005
This study investigated homocysteine & dementia. A total of 1092 subjects without dementia (667 women and 425 men; average age, 76 years) were followed for an average of 8 years. Their homocysteine levels were monitored. The study used multivariable proportional-hazards regression to adjust for age, sex, apolipoprotein E genotype, vascular risk factors other than homocysteine, and plasma levels of folate and vitamins B12 and B6. Over a median follow-up period of eight years, dementia developed in 111 subjects, including 83 given a diagnosis of Alzheimer’s disease. The multivariable-adjusted relative risk of dementia was 1.4 (95 percent confidence interval, 1.1 to 1.9) for each increase of 1 SD in the log-transformed homocysteine value either at base line or eight years earlier. The relative risk of Alzheimer’s disease was 1.8 (95 percent confidence interval, 1.3 to 2.5) per increase of 1 SD at base line and 1.6 (95 percent confidence interval, 1.2 to 2.1) per increase of 1 SD eight years before base line. With a plasma homocysteine level greater than 14 micromol per liter, the risk of Alzheimer’s disease nearly doubled.
Conclusions: An increased plasma homocysteine level is a strong, independent risk factor for the development of dementia and Alzheimer’s disease.
Seshadri S et al, Plasma homocysteine as a risk factor for dementia and Alzheimer’s disease.N Engl J Med., 346(7):476-83, 2002
Scientists at Oxford University’s OPTIMA project* ran a study to look for a link between vitamin D & Alzheimer’s. Participants were comprised of 255 people with definite or probable Alzheimer’s and 260 healthy elderly people. The study looked at the gene for the vitamin D receptor, which manages the body’s response to vitamin D.
Findings were that there does appear to be a link. Two slight changes in the genetic code which makes up the gene for the vitamin D receptor were associated with risk of Alzheimer’s. These are preliminary findings, and more research is needed to understand their significance.
Lehmann DJ, Refsum H, Warden DR, Medway C, Wilcock GK, Smith AD (2011) The vitamin D receptor gene is associated with Alzheimer’s disease. Neurosci Lett. Oct 24;504(2):79-82.
*OPTIMA is led by Professor David Smith who is also on our Scientific Advisory Board
This study investigated dementia & Alzheimer’s. Over 8000 over-65s were monitored for development of dementia and Alzheimer’s over a 4 year period and details of their dietary habits were analysed. Daily consumption of fruits and vegetables was found to be associated with a decreased risk of all types of dementia. Weekly consumption of fish was also associated with a decreased risk of all dementias and Alzheimer’s Disease but only amongst those people who do not have the genetic variation called ApoE4. The regular use of omega-3 supplements was associated with a slight decreased risk of all dementias. However, the regular use of omega-6 supplements, where it was not balanced with the use of omega-3 supplements or fish, actually doubled the risk developing dementia amongst those who do not have the ApoE4 gene. In summary, frequent consumption of fruits and vegetables, fish, and omega-3 rich oils may decrease the risk of dementia and Alzheimer disease, especially among ApoE4 non-carriers. In addition, balance of the omega 3:6 ratio may also be an integral risk factor, although further research is warranted.
Gateau P et al.,’Dietary patterns and risk of dementia: The Three-City cohort study, Barberger’. Neurology. 2007 Nov 13;69(20):1921-30
This study investigated folate & Alzheimer’s. Folate helps the body to process homocysteine, which is associated with a higher risk of cardiovascular disease and stroke, and may also increase the risk of Alzheimer’s disease. Researchers studied the diets of 965 people age 65 and older who did not have dementia when the six-year study began.
Results demonstrated 192 cases of incident AD. The highest quartile of total folate intake was related to a lower risk of AD (hazard ratio, 0.5; 95% confidence interval, 0.3-0.9; P=.02 for trend) after adjustment for age, sex, education, ethnic group, the epsilon4 allele of apolipoprotein E, diabetes mellitus, hypertension, current smoking, heart disease, stroke, and vitamin B6 and B12 levels. Vitamin B6 and B12 levels were not related to the risk of AD.
Conclusions: Higher folate intake may decrease the risk of AD independent of other risk factors and levels of vitamins B6 and B12. These results require confirmation with clinical trials.
Luchsinger et al., ‘Relation of higher folate intake to lower risk of Alzheimer disease in the elderly’, Arch Neurol.;64(1):86-92, 2007
This was a meta-analysis* of eight studies, involving almost 9,000 subjects. The results found that at 5 µmol/l increase in homocysteine level was associated with a 35% increase in incidence of dementia.
The researchers could not conclude that raised homocysteine is an actual cause. However, they did estimate that if it was causal, we could expect an approximate 20% reduction in risk of dementia from treatment with folic acid and B12.
A study conducted by UCLA School of Medicine researchers of 732 elderly people given MRI brain scans finds that those with raised homocysteine levels have greater brain shrinkage regardless of age and diagnosis. Among those with cognitive impairment, the greater the homocysteine level the greater was the brain atrophy. The authors state ‘ Vitamin B supplements may help prevent homocysteine-related atrophy in Alzheimer’s disease by possibly reducing homocysteine levels’.
This study investigated nutrients for autism. It involved giving 141 children and adults with autism, a multi-nutrient formula containing a broad range of vitamins and minerals or a placebo. Their symptoms were assessed before and after the study which ran for three months. Fifty-three of the children in the study also had blood measures taken of nutritional and metabolic status(biomarkers) before and after.
In terms of symptoms, the supplemented group had significantly greater improvements than the placebo group on the following scores: Parental Global Impressions (PGI-R), Hyperactivity, Tantrumming, Overall and Receptive Language. The change in the PGI-R was strongly associated with a number of the biomarkers suggesting that there is a relationship between changes in biomarkers and changes in symptoms.
Levels of many vitamins, minerals, and biomarkers improved including markers of oxidative stress thought to be elevated in autism, as well as markers of key biological processes such as methylation and sulphation.
Adams JB, Audhya T, McDonough-Means S, Rubin RA, Quig D, Geis E, Gehn E, Loresto M, Mitchell J, Atwood S, Barnhouse S, Lee W. (2011) Effect of a vitamin/mineral supplement on children and adults with autism. BMC Pediatr. 11:111.
This study investigated low carbohydrate diet & Alzheimer’s. In this study 23 Adults with Mild Cognitive Impairment were randomly assigned either a low or high carbohydrate diet. Body composition, metabolic parameters, and memory and mood measures were obtained before and after the intervention. There was no group difference in demographics, level of memory impairment, or metabolic parameters before the intervention. At the end of the intervention period, there were significant reductions in weight, waist circumference and glucose levels for the low carbohydrate group. Furthermore, verbal memory function was significantly improved for the low carbohydrate subjects. Depressive symptoms were not affected by either diet. These findings indicate that ketosis induced by very low carbohydrate consumption, even in the short-term, can improve cognitive function in older adults with greater risk for Alzheimer’s disease. This study is a first in its field and the findings warrant further investigation.
Krikorian, R., Shidler, M. D., Dangelo, K., Couch, S. C., Benoit, S. C., & Clegg, D. J. (2012). Dietary ketosis enhances memory in mild cognitive impairment. Neurobiology of aging, 33(2), 425.e19–425.e4.25E27. https://doi.org/10.1016/j.neurobiolaging.2010.10.006
This study explored nutrition in children. This study sought to examine the relationship between food poverty (defined as those individuals who go to school or bed hungry because there is not enough food at home) and food consumption, health and life satisfaction among 8424 school children from the Republic of Ireland, aged between 10 and 17 years. Each participant completed a questionnaire, which assessed social class, dietary composition, eating habits and the presence of emotional and physical symptoms including feeling low, nervous, bad tempered, afraid, tired, exhausted and suffering from headache, stomachache, backache, dizziness and neck of shoulder pain. The questionnaire also assessed the children’s feelings about life and life satisfaction.
Children experiencing food poverty reported lower intakes of fruit, vegetables and brown bread and higher intakes of crisps, fried potatoes and hamburgers. They also had increased risk of experiencing somatic and mental symptoms and experienced negative health perceptions and lower life satisfaction.
Molcho, M et al., ‘Food poverty and health among schoolchildren in Ireland: findings from the Health Behaviour in School-aged Children (HBSC) study’, Public Health Nutrition, 10(4), 364-370, 2006 June
This study investigated nutrients & brain aging. In this ground-breaking study, 104 healthy elderly people (with an average age of 87) had blood levels of 30 different nutrients measured. Mean age was 87 ± 10 years and 62% of subjects were female. Results suggested that two NBPs associated with more favourable cognitive and MRI measures: one high in plasma vitamins B (B1, B2, B6, folate, and B12), C, D, and E, and another high in plasma marine ω-3 fatty acids. A third pattern characterized by high trans fat was associated with less favourable cognitive function and less total cerebral brain volume. Depression attenuated the relationship between the marine ω-3 pattern and white matter hyperintensity volume.
Conclusion:
Distinct nutrient biomarker patterns detected in plasma are interpretable and account for a significant degree of variance in both cognitive function and brain volume. Objective and multivariate approaches to the study of nutrition in brain health warrant further study. These findings should be confirmed in a separate population.
This study investigated omega 3 and brain ageing. An Italian study measured the blood levels of essential fats in 935 elderly Italians and compared these with their cognitive function, which ranged from normal cognitive function through to dementia. The researchers found those with the worst cognitive function, had the lowest level of essential fats, especially omega-3.
Cherubini et al. ‘Low plasma N-3 fatty acids and dementia in older persons: the InCHIANTI study.’ J Gerontol A Biol Sci Med Sci. 2007 Oct;62(10):1120-6.
The study investigated essential fatty acids & mental health. A review finds that there is an association between depression and low dietary intake of omega-3 fatty acids and that low levels of the fatty acids in red blood cell membranes are found in both depressive and schizophrenic patients. Five of six double-blind, placebo-controlled trials in schizophrenia, and four of six such trials in depression, have reported therapeutic benefit from omega-3 fatty acids in particularly when EPA is added on to existing psychotropic medication. Individual clinical trials have suggested benefits of EPA treatment in borderline personality disorder and of combined omega-3 and omega-6 fatty acid treatment for attention-deficit hyperactivity disorder. The evidence to date supports the use of omega-3 fatty acids in the management of treatment unresponsive depression and schizophrenia alongside medication. As these conditions are associated with increased risk of coronary heart disease and diabetes mellitus, omega-3 fatty acids should also benefit the physical state of these patients.
Peet & Stokes, ‘Omega-3 fatty acids in the treatment of psychiatric disorders ‘, Drugs, 65(8):1051-9, 2005
