n these rapidly developing years, parents are highly concerned about their children’s performance in all aspects of life. Many of them are willing, without having second thoughts, to spend more on anything that will make their children “brilliant or smart kids”. At the same time, various products and supplements, which are supposed to be “food for brain”, are mushrooming in the market. How effective are they in improving your child’s IQ? Understanding the role of nutrition in brain development may help you answer this question.
Early nutrition for brain health
Brain development follows a highly ordered sequence of events through its approximately one billion cells that communicate with each other via much specialised interconnections. The brain is a part of the central nervous system, and plays a decisive role in controlling many bodily functions, including both voluntary activities (such as walking or speaking) and involuntary ones (such as breathing or blinking).
Although brain development is a lifelong process, many factors modulate the effects of nutrition on mental health, including age and genes. Critical periods of neurodevelopment occur during prenatal and postnatal life, indicating that optimal nutrition is important especially during these early stages of the life cycle. Recent findings show that infants are at major risk of impaired neurodevelopment and neurobehaviour, including multiple cognitive deficits in memory and learning if reduction in nutrient supply happens during intrauterine growth. Despite some inconsistencies between studies, effects on IQ, depression, ADHD and schizophrenia have been documented.
Nutrients function and priorities
All nutrients are important for neuronal cell growth and development, but some appear to have greater effects during the late fetal and early neonatal time periods. The importance of these nutrients has been established primarily through nutrient deficit studies and through knowledge of their role in the specific biochemical pathway of brain development.
1. Protein and energy balance
There are numerous links between protein-energy balance and the brain development. Protein-energy malnutrition between 24 and 44 weeks post conception may result in intrauterine growth retardation and is usually due to maternal hypertension or severe malnutrition during pregnancy. Pregnant mothers are advised to eat sufficiently balanced meals as studies show that babies who are born smaller than gestational age have poorer cognition and school performance compared to babies with normal weights. In Malaysia, high energy diets and a sedentary lifestyle are leading to increased prevalence of obesity and diabetes to numbers that are quite alarming. Children should be taught about healthy food from as young as possible to avoid improper choices. Adherence to our food pyramid is the key.
2. n-3 fatty acids
Many products out there in the market claim to be enriched with DHA, EPA or ALA. But do you know what these nutrients really are and what are the natural sources? n-3 fatty acids are essential dietary nutrient which provides DHA. DHA plays a vital role in cognition and mental health. It enhances memory, mood and behavior, and reduces the symptoms of depression. The n-3 fatty acids also include α-linolenic acid and EPA. Fatty acid deprivation may affect brain development at multiple levels and this is still undergoing detailed research. The richest dietary sources of n-3 fatty acids are fish and sea foods. Poultry and eggs provide lower, but important sources of EPA and DHA. The major sources of ALA are soybean and canola oil; flax seed oil and some nuts are also high in ALA.
Iron has several vital functions in the body. It mainly serves as a carrier of oxygen throughout the body including the brain. Several structures in the brain have a high iron content of the same magnitude as observed in the liver. Based on scientific observation, the lower iron content of the brain in iron-deficient growing rats cannot be increased by giving iron later on. This study strongly suggests that the supply of iron to brain cells takes place during an early phase of brain development and that, as such, early iron deficiency may lead to irreparable damage to brain cells. Children with iron deficiencies demonstrate impaired intellectual performance. Sources of iron include animal protein, beans, rice, corn, apricots and liver.
4. Copper and zinc
Copper and zinc have critical actions in neurodevelopment, neurotransmitter synthesis, energy metabolism, antioxidant defence and DNA synthesis. Low plasma copper is linked with Alzheimer’s disease whereas zinc deficiency is linked with ADHD disorder in children. Deficiencies are less likely to happen in healthy children who are on a well-balanced diet as it can be found abundantly in many foods. Good sources of copper are sea food, nuts, whole grain cereals, legumes and chocolate while zinc can be found in lean red meat, liver, seafood and dairy products.
In summary, proper nutrition with adequate amounts of necessary micronutrients, protein and calories given at the appropriate time may ensure normal brain development. There is no super food or single nutrient which can develop a “brilliant brain” as this requires healthy interactions between nutrition and a few other factors such as environment, genetics and age. Considerable evidence suggests that incorporation of advice on diet and physical activity will undoubtedly be of benefit in the optimizing brain development.
Ref. Malaysians Dietitians’ Association