Experts on factors which influence brain development in-utero and after birth

You are what you eat – so we are told, but can nutrition have an impact on how brainy your baby is?

Later this week (Thursday 8 December), scientific experts from New Zealand and Australia meet for a one-day symposium at Massey University’s Albany campus in Auckland to discuss this very subject.

In advance of the symposium, the Science Media Centre asked a selection of speakers for their expert view on the latest scientific evidence in relation to which nutrients are required to optimise brain development in pregnancy, infancy and childhood.

Feel free to use the quotes below in your articles – contact the SMC to talk to the researchers or for further details.

Iron and brain development

Associate Professor Jane Coad from Massey University comments:

“Iron during foetal and neonatal development is essential for normal neurodevelopment. Deficiency can have life-long consequences. However, iron deficiency is one of the most common nutritional problems in the world and pregnant women, infants and children are the most vulnerable.

“The neonate has little capacity to increase iron absorption in times of deficiency and, paradoxically, also has much less capability to cope with iron excess and protect itself at a time when it is particularly vulnerable to iron toxicity. Optimising iron intake both pre-conceptually and during pregnancy, and recognising infants at risk, has the potential to optimise brain development – indeed it is thought that IQ could be raised by 10 points on average worldwide if all infants achieved optimal levels of nutrition.”

Iodine and brain development

Dr Sheila Skeaff from the University of Otago comments:

“Iodine is an essential element needed for normal growth and development; growing brains need iodine and that is why pregnant women and their babies need a good supply of iodine in their diets. The mandatory fortification of bread with iodised salt should increase the iodine intakes of New Zealand children and adults so they are getting enough iodine from foods, however, the Ministry of Health recommends pregnant and lactating women take a supplement containing 150µg of iodine each day.

“Unfortunately, the evidence to support the usefulness of this recommendation is conflicting. Some studies have shown that iodine supplementation in pregnancy improves aspects of brain function in the babies born to supplemented mothers while a more recent study has shown that some aspects of brain development are poorer in mothers who take an iodine supplement. Until more definitive studies come to light, the daily consumption of iodine-fortified breads, use of iodised salt, and regular intake of eggs, milk, dairy products and properly cooked fish and other seafood can all help increase the dietary intake of iodine. ”

Omega 3 fatty acids and brain development

Dr Carmel Collins from the Child Nutrition Research Centre, Flinders Medical Centre, Australia, comments:

“The effect of maternal supplementation of omega-3 long chain polyunsaturated fatty acids (n-3 LCPUFA) on neuro-developmental outcomes for children born at term remains unclear, whereas n-3 LCPUFA supplementation of women expressing milk for their preterm infants does improve the child’s neurodevelopment.

“Generally, supplementation of infant formula for preterm rather than term infants has demonstrated more consistent, positive effects neuro-behavioural development.”

Vitamin D and brain development

Associate Professor Darryl Eyles from the Queensland Brain Institute, University of Queensland, Australia, comments:

“The evidence that adequate levels of vitamin D are required for normal brain development has been largely informed by animal studies. When the vitamin is depleted from the maternal diet it would appear both brain structure and function are adversely affected in the offspring. For instance, certain structures within the brain such as the lateral ventricles are increased just as we see in many patients with schizophrenia. The offspring also have abnormalities in behaviours linked to abnormal dopamine/glutamate signalling, another common feature of the disease.”

“The developing brain is the end result of a carefully co-ordinated series of events incorporating cell proliferation, elimination, and differentiation. We believe the role of vitamin D is to apply the brakes to normal cell proliferation and promote the differentiation of selected cellular phenotypes such as dopaminergic neurons.

“It is generally acknowledged, though there is some dispute, that maintaining a blood level of 25Hydroxy-vitamin D (the most reliable form of the vitamin to measure) above 50nM will ensure adequate vitamin D status for health in infants and adults. There is no evidence that supra-physiological levels are required in pregnancy.

“Dietary sources for precursors for vitamin D are particularly poor and the greatest contribution to an individual’s vitamin D status is likely to be from sunlight exposure and supplementation. The issue of how much sunlight exposure to obtain sufficient UVb radiation (290-315nM) in order to make the precursor for vitamin D in skin is governed by many environmental factors such as season, latitude and time of day. Adequate sun exposure without causing sunburn should be sufficient for most mothers and infants in New Zealand. However, given New Zealand’s low latitude, if the mother is concerned she should discuss supplementation with their GP, particularly during the winter/spring months.”

Nutrition supplements and brain development

Dr Lisa Houghton from the University of Otago comments:

“Folic acid is a B vitamin which helps prevent birth defects of the brain and spinal cord. These defects occur very early in pregnancy, often before a woman even knows that she is pregnant. It is therefore recommended that all women start taking a 0.8mg folic acid supplement at least one month before pregnancy and continue to take folic acid until the end of the first trimester. Folic acid supplements can be purchased at pharmacies, or at a lower cost when prescribed by your doctor or midwife.

“Vitamin, mineral and health supplements other than folic acid should only be taken in consultation with your doctor or midwife.

“Supplements containing preformed vitamin A (retinol) are not recommended during pregnancy, unless under supervision of doctor or midwife. A high intake of vitamin A during early pregnancy is associated with increased risk of birth defects such as cleft lip and palate and abnormalities of the central nervous system. Care must be taken to ensure that the total daily intake of vitamin A from any supplements taken, including fish oils, does not exceed the safe upper level of 3000 micrograms of retinol equivalents (RE) per day.

“Omega-3 fatty acids are important for both neurological and early visual development of the baby. According to the New Zealand Ministry of Health (2006), ‘Foods fortified with fish oil (such as milk or bread) or fish oils themselves may be a useful way to increase the omega-3 content of the diet. The total amount of omega-3s in the diet should not exceed the safe upper level of 3g per day.'”