Brain nutrients- do we get enough to stay switched on?

By Linda McCourt Scott (MA (Oxon), MSc Nutritional Medicine, author of Natural Home Pharmacy)

The human brain constitutes a mere 2% of our total body weight yet uses between 20-50% of our energy intake from food. This super-functioning organ requires energy to constantly power its electrical activity, even at rest. Twenty-three vitamins and minerals are required directly and indirectly for this process.  If the supply of one or more of these nutrients is deficient then glucose utilisation is impaired and the first part of the brain to suffer is the frontal lobe, the part concerned with higher thought, reasoning and socialisation. This results in reduced intellectual capability and emotional control. The more primitive part of the brain, which is the seat of the basic emotions such as anger and desire, then becomes dominant and our behaviour becomes more aggressive, violent, impulsive, selfish and unreasonable. Sound familiar?

Studies show that vitamin and mineral deficiencies are widespread even in affluent countries (80% people in developed countries have one or more nutrient deficiencies). These deficiencies are affecting brain function in a myriad of ways. For instance it has been shown that the intellectual performance of between 30-50% of children in developed countries can be significantly improved through vitamin and mineral supplementation. Studies on institutionalised juvenile delinquents also found that vitamin and mineral supplements not only increased their IQ scores, they also dramatically reduced the incidence abnormal brain wave patterns and antisocial, violent behavioural incidents. Poor nutrition therefore appears to be an important cause of both academic difficulties and antisocial behaviour in modern adolescents.

And it seems the same applies to adults. Multiple studies have demonstrated that as soon as vitamin and mineral status improves through supplementation, intellectual performance, as assessed using standardised tests of memory, abstract thinking and problem solving abilities, also improves. Further studies have shown that the higher the levels of the antioxidant vitamins C and E and the B complex vitamins (including folate) are in an adult’s blood, the better the intellectual performance. Adults with the highest levels were shown to perform 25% better than those with the lowest levels. Other studies have shown that regardless of age and education, people who take supplements show superior intellectual function to those who don’t. Furthermore older subjects who took supplements long-term scored as well as or better than younger adults on memory tests. This is particularly interesting as memory loss is seen as an inevitable consequence of ageing, yet may simply reflect a deficiency of brain nutrients. Vitamin deficiencies are associated with cruel consequences for ageing brains. Men and women older 60 years who are deficient in any of the B vitamins or vitamin C not only under perform on mental tests, they are also much more likely to be emotionally unstable, depressed, excitable, nervous, anxious, angry, irritable, easily discouraged and fatigued.

Calcium, magnesium, iron, selenium and zinc are particularly important minerals for the production of brain energy and brain function. Minor deficiencies of these minerals can be associated with reduced intellectual function, mental apathy, depression, anxiety and fatigue, all of which can be reversed with appropriate supplementation.

The other critical nutrient determining brain function is fat, which comprises 60% of the brain.  If our brain is not provided with the correct balance of different fatty acids it is forced to use whatever is supplied by our diet, with far-reaching consequences. If we eat predominantly saturated fats (lots of meat and dairy products such as hamburgers, sausages, full-fat milk shakes, pizzas etc) brain structure and performance are adversely affected. This is because the outer membranes of our brain cells, which are composed largely of fatty acids, harden and stiffen if saturated fatty acids are used instead of unsaturated fatty acids. Saturated fats do not have the molecular flexibility of unsaturated fats (compare the texture of lard with olive oil).

As a result neurotransmitters, the chemicals that carry signals between brain cells, cannot easily ‘dock’ onto receptor sites on the cell surfaces and brain function slows down. If the brain signalling system is hampered our ability to think, reason and memorise, as well as our mood, is impaired.

When laboratory animals are fed a high saturated fat diet they don’t learn as quickly or perform as well on a wide variety of tests compared with animals fed a balanced fat diet. The more saturated fat the animals are fed, the less well they perform in every area, and the longer animals eat a high saturated fat diet, the more they ‘dumb down’. The bad news is that the amount of saturated fat needed to produce memory malfunction in animals is comparable with the typical saturated fat content of many people’s diets today. The good news however is that it is possible to reverse these deleterious brain changes by:

  • Reducing the saturated fat content to around 15-20% of our calorie intake
  • Increasing our intake of the all-important omega-3 fatty acids, especially in the form of DHA and EPA-rich fish (salmon, mackerel, sardines, mackerel, trout and tuna) or as fish oil supplements. Other rich sources of omega-3 fatty acids include linseeds, green leafy vegetables, canola oil and walnuts.

Whether we eat a nutrient-rich or nutrient-poor diet can, it seems, have dramatic ramifications on our brain function. Persistently negative moods, emotional problems and problems with memory and mental tasks should alert us to the possibility of marginal micronutrient deficiencies. Appropriate dietary changes and vitamin and mineral supplementation are therefore recommended to make sure you experience optimal mental and emotional health and avoid any age-related decline in brain function.