Feeding the Brain: A Lifelong Mission 12 Feb 2013
Epidemiology is always valuable for generating hypotheses based on statistical associations. However, statistical relationships do not characterize cause and care must be taken when teasing out the relative contribution of different factors.
Case in point, Nguyen and colleagues analyzed measures of cognitive function in 5,635 children (6-16 years) and serum folate and vitamin B12 concentrations collected from 1988-1994, before mandatory folate fortification of grains. Mean folate and vitamin B12 concentrations were 8.5 ng/mL and 631 pg/mL, respectively. They found significant relationships among folate concentrations and measures of cognitive performance (math, reading, digit span test and block design scores). The authors acknowledge that sex, race/ethnicity, income- poverty ratio, and other unobserved variables may confound the interpretation. There are few studies of B vitamin status and cognition in children.
Most of the research is found in older adults. Using a randomized controlled trial (RCT), Walker and colleagues reported that B vitamin supplementation helped prevent cognitive decline in community dwelling older adults. While drug interventions to treat Alzheimers have failed, there is evidence that the B vitamins are important in maintaining cognitive function.
Folate intakes have improved in countries with mandatory fortification programs. Because grains are often consumed at breakfast, and many ready-to-eat cereals are voluntarily fortified, breakfast consumers usually have higher micronutrient intakes. In 2012, the CDC Second Nutrition Report reports mean serum folate concentrations of 16.1 and 11.2 ng/mL for 6-11y and 12-19y, and mean vitamin B12 concentrations of 728 and 510 pg/mL for the same age groups, respectively. However, one mustn’t forget that nutrients other than folate and vitamin B12 are associated with cognitive function.
Iron deficiency can also compromise child development. The brain is primarily composed of lipid, containing 97% of the docosahexaenoic acid (DHA) content of our body, and lower red blood cell levels of DHA have been associated with markers of accelerated brain aging. Richardson and colleagues reported that DHA supplementation (600 mg/d) improved reading performance in 7-9 year old children who were underperforming in reading.
Bottomline: Good nutrition is the foundation for brain development and learning. Throughout life.-mm-
Nguyen CT, Gracely EJ, Lee BK. Serum folate but not vitamin B12 concentrations are positively correlated with cognitive test scores in children aged 6-16 years. 2013 J Nutr doi:10.3945/jn.112.166165