We have talked about the burgeoning data linking food with mood, behavior and cognition.
I have just seen a new study that really adds to our knowledge and contributes information that we can all use.
Scientists in Europe, Australia and Indonesia have published data in the American Journal of Clinical Nutrition suggesting that nutrition can improve verbal learning and memory in schoolchildren.
This study was undertaken by the NEMO study group (Nutrition Enhancement for Mental Optimization) that consists of the Unilever Food and Health Research Institute (Vlaardingen, The Netherlands); CSIRO, Human Nutrition (Adelaide, Australia) and the SEAMEO-TROPMED Regional Center for Community Nutrition, University of Indonesia (Jakarta Pusat, Indonesia).
It was a 12-month study of 780 children in Australia and Indonesia in which the researchers evaluated the effects of adding a specific vitamin and mineral mixture to a daily drink.
The study population consisted of 396 well-nourished children in Australia and 384 poorly nourished children in Indonesia. In each country, the children were randomly allocated to one of four groups, receiving a drink with either:
- A mixture of micronutrients (iron, zinc, folate and vitamins A, B-6, B-12 and C)
- Fish oil (DHA and EPA)
- Both the micronutrient mixture and the fish oil
- Nothing added, i.e. placebo
In Australia, children who received the daily drink with the added vitamin and mineral mixture performed significantly better on tests of mental performance tests than children in a control group who received the drink but without added nutrients. In Indonesia a similar trend was observed, but this time only in the girls.
After twelve months, children in Australia who received the drink with the nutrient mix showed higher blood levels of these micronutrients, which means that their bodies were taking up the nutrients. In addition, they performed significantly better on tests measuring their learning and memory capabilities compared to children in the other groups. A similar trend was observed in Indonesia, but only in the girls. The addition of fish oil to the fortified drink did not conclusively show any additional effects on cognition.
This study adds to the mounting evidence that nutrition plays an important role in cognitive development in children, even in children who are enjoying a “normal” diet. Deficiencies in iron and iodine have been linked to impaired cognitive development in young children for over a century and there is now emerging evidence that deficiencies in zinc, folate and vitamin B12 may each compromise mental development in children. More recently, fish oils (EPA, DHA) have also been linked to child cognitive development.
Most previous studies have focused on deficiencies in single nutrients in young age groups, despite the well-known observation that the brain continues to grow and develop during childhood, adolescence and early adulthood. Little is known about the role of nutrition on mental development after the age of 2. In addition very other few studies have looked at the effect of offering a mix of nutrients. Until this study, there were very few randomized controlled intervention studies assessing the impact of a multiple-micronutrient intervention on cognitive function in schoolchildren.
The investigators recommend further research to investigate the exact role of DHA and EPA in healthy school-aged children. Another research focus is the further optimization of cognitive development tests with respect to their validity and sensitivity across cultures. The scientists suggest that the smaller effects of the vitamins and minerals in Indonesia could be a result of a lower sensitivity of the cognitive tests in that country.
This research raises many interesting points:
- Is it possible that the healthy Australian diet is actually nothing of the sort?
- Is it possible that if the diet is adequate, that “super-nutrition” can help a child to exceed his or her potential?
- Are there key ages when nutrition can help, or is the effect maintained across the age range?
- Does nutritional supplementation have a long-term impact on a child?
- Have we even found the optimal mixture for child cognitive development? Might higher amounts of any nutrients – particularly fish oils – produce better effects, or might they be toxic, as we saw in the case of vitamin A supplementation?
- Are we using the correct cognitive development tests to pick up changes in different cultures? As an example, could the smaller effects of the vitamins and minerals in Indonesia be a result of a lower sensitivity of the cognitive tests in that country? Or is it that the children are also missing out on some other trace nutrients?
Many questions, but the take home message is this: careful nutritional supplementation may have considerable benefits to a child, even one growing up in an affluent culture.
“Learning is a weightless treasure you always carry easily.”