There are many hundreds of studies relating brain function to nutrition and I am never sure where to begin trying to relay these to you via this blog – the volume of available evidence always seems so daunting! Last week I wrote about just one nutrient, vitamin B12 and cognition/mental function. Fortunately for me one group of scientists, headed by Dr Fernando Gomez-Pinilla, have now published an extensive review paper (1) which analyzed more than 160 studies investigating various different foods and nutrients and how they affect the brain. A concise press release was published on the UCLA newsroom website (2) and I am going to pick out some of the major findings in my post today.
Dr Fernando Gómez-Pinilla is a member of California’s largest university, UCLA, and works within the Brain Research Institute and Brain Injury Research Centre. Together with his colleagues he decided to look into how a balanced diet and regular exercise can protect the brain and ward off mental disorders. Dr Gomez-Pinilla looked at over 160 published studies and believes that food acts like a pharmaceutical agent in the way it can affect the brain. He also believes that diet, exercise and sleep can, potentially, alter brain health and mental function.
It has long been suspected that different nutrients can affect cognitive (mental) processes and emotions. The paper reviews new evidence exploring the nutrients and the mechanisms by which they may be responsible for the action of diet on brain health and mental function. So many key nutrients came up as being important. Omega 3 fatty acids, flavonoids, curcumin, B vitamins, Vitamin D, Vitamin E, Vitamin C, Calcium, zinc, selenium and carotenoids, to name but a few! The mechanisms by which they positively affect our brain function and cognition are complex and intricate.
Omega 3 fatty acids, found most abundantly in oily fish (such as salmon, mackerel and trout), flaxseeds and walnuts came up trumps, yet again! These fats are essential for normal brain function and the research suggests that they provide many benefits, including improving learning and memory and helping to fight against mental disorders such as depression, mood disorders, schizophrenia, and dementia. In contrast to the healthy effects of diets that are rich in omega-3 fatty acids, the studies seem to indicate that diets high in trans fats (often found in processed foods) and saturated fats adversely affect cognition.
The brain is highly susceptible to oxidative damage (by free radicals). Antioxidants provided by the diet (such as vitamins A, C and E and flavonoids), found most abundantly in fruits and vegetables, seem very important in protection (many of my previous posts have discussed the importance of antioxidant nutrients).
Surprisingly what you eat may also affect future generations. Dr Gomez-Pinilla found that recent research also supports the hypothesis that health can be passed down through generations, and a number of innovative studies point to the possibility that the effects of diet on mental health can also be transmitted across generations “Evidence indicates that what you eat can affect your grandchildren’s brain molecules“.
Another interesting reference to brain structure and health was made by a group of scientists (also from UCLA) in a recently published paper (3) which was highlighted in The Times newspaper (4) this month. The shocking headline reported that our peak age for mental health is 39 years old!!
The study was small, involving 72 men between the ages of 23-83, and the researchers evaluated brain function by testing speed of movement via finger tapping – how many times participants could tap their finger in 10 seconds. Usually the speed of response slows as we age probably because the fatty ‘myelin’ sheath surrounding our nerves starts to deteriorate which causes responses to slow. The researchers found that myelination of the brain neurones (nerves) was significantly correlated to finger tapping speed and reached a peak at 39 years of age, declining thereafter. Keeping our brain myelin ‘healthy’ seems to be very important for this specific form of brain function (called maximum motor speed). Although the study only involved men it is likely to be the same in women.
In The Times newspaper the authors reveal how myelin can be damaged via excess alcohol: “The brain is made of fat, so when you get drunk you’re basically dissolving your brain. A glass of wine may have a beneficial effect, but if you get drunk it’s malfunctioning. As the alcohol leaves the brain tries to repair itself but if you keep doing it, it won’t repair itself fully” (4)
The researchers also suggest that the decline in brain myelination can be diminished (GREAT NEWS!), even halted, by regular exercise, good sleep and a healthy diet including at least one gram of fish oil a day, to provide omega 3 fatty acids, and plenty of colourful vegetables and fruits which are rich in antioxidants that help to prevent free radical damage, which may damage myelin.
The newspaper article also ends on a more positive note. Although the area of the brain tested seems to declines after the age of 39 there are other areas where the circuitry still repairs itself: wisdom, for instance, is apparently strengthened with age “ most older people have better impulse control than when they were younger because as they age, this circuit continues to myelinate and brings all their knowledge online so that they can make a decision better and faster, even though their movements may be slower”. The researchers give the following example “It’s the Michael Jordan effect. He retired as a basket-ball player because those neurons controlling his speed and athleticism had started breaking down, but he went on to run a multi-million-dollar empire, which he probably couldn’t have done at 25”
The take home message from these published papers is to try and live a healthy lifestyle, to exercise, get good sleep and eat an unprocessed diet rich in nutrients and omega 3 fatty acids. Future research is bound to throw up more dietary wisdom. As Dr Gomez-Pinilla says: “Understanding the molecular basis of the effects of food on cognition will help us to determine how best to manipulate diet in order to increase the resistance of neurons to insults and promote mental fitness”(1).
If you are not a lover of oily fish then you may wish to take an omega 3 supplement providing around 250mg EPA and 250mg DHA per day. For vegans and vegetarians a flaxseed oil supplement providing around 500mg alpha-linolenic acid per day may be useful. Antioxidants are best provided by vegetables and fruits, if you worry that you are not getting at least 5 portions a day you may consider taking a low dose multi-vitamin and mineral supplement. I personally prefer ‘food-state’ nutrients as they are easily absorbed by the body and not made with isolated chemicals.
(1)Gómez-Pinilla F et al. Brain foods: the effects of nutrients on brain function. Nature Reviews Neuroscience, 2008; 9 (7):568-578
(2) UCLA newsroom 09/07/08 Scientists learn how what you eat affects your brain byStuart Wolpert
(3) Bartzokis G et al. 2008. Lifespan trajectory of myelin integrity and maximum motor speed. Neurobiol Aging. 2008 Oct 14. [Epub ahead of print]
(4)Alexandra Blair. Thursday November 6th 2008. If 39 is our mental peak then my brain is in big trouble. The Times 2. Page 6-7
Written by Ani Kowal
Related posts:
