Junk Food May Limit Children’s Intelligence and Learning Ability
There is a clear impact of nutrition on the potential development of Alzheimer’s disease and other late-life cognitive disorders. Green vegetables, berries, and other plant foods reduce risk, whereas animal products and processed foods increase risk.1-4 However, the damaging effects of unhealthy foods on the brain occurs throughout life. Research now suggests that the typical American childhood diet including burgers, pasta, pizza, chicken nuggets, french fries, processed sweetened cold cereals, sweets and soda negatively affects school performance and learning. Overall math performance in the U.S. lags far behind many other developed nations,5 and it is likely that the nutrient-poor American diet is a significant contributing factor.
We as parents are strongly committed to supporting our children’s academic achievement. We want the best for our children, and we take an active interest in their schooling; we do everything we can to make sure that they will be well educated and able to compete as working adults in our increasingly technological world. However, how many parents think about the impact of the foods they give their children on their academic performance?
Parents must give their children’s brains the right raw materials with which to learn — and start early. Breast milk provides a DHA-rich foundation for a healthy brain, and when solid foods are added, their nutritional quality is of paramount importance for the brain’s continued development. Several studies have now found that dietary patterns in early childhood affect IQ scores years later. In one study, greater consumption of fruits and vegetables upon introducing solid foods was associated with higher IQ and better memory skills when at 4 years of age.6 Similarly in another study, children who regularly ate cookies, chocolate, other sweets, soda, and chips during the first two years of life showed decreased IQ at age 8 compared to children who did not eat these foods. Nutrition during this formative period has a meaningful long-term effect, providing building blocks to construct the growing brain.7 The brain is highly susceptible to oxidative stress, so a healthful, antioxidant-rich diet is especially beneficial for the brain and is likely involved in this link between natural plant foods and higher IQ scores.
Young children who are fed processed, nutrient-poor foods are likely to become unhealthy teenagers, and eventually unhealthy adults. Now twenty-three percent of teens in the U.S. are prediabetic or diabetic, 22% have high or borderline high LDL cholesterol levels, and 14% have hypertension or prehypertension.8
A recent study tested cognitive abilities and performed brain MRIs on teens with and without metabolic syndrome, a combination of at least three diet-related metabolic abnormalities among a list including insulin resistance, high triglycerides and hypertension. The teens with metabolic syndrome had lower spelling and math scores, lower IQs, and reduced attention span. Their brain MRIs showed a smaller hippocampus, especially in those with insulin resistance — extremely important since the hippocampus is a part of the brain involved in learning new information.9 This means that our American obesity-promoting, diabetic promoting diet actually can cause parts of the brain to shrink. The researchers concluded that insulin resistance and other components of the metabolic syndrome, as a result of a poor diet, may impair teenagers’ academic performance, and maybe even their learning abilities throughout their lifetime.
The time to feed your children healthfully is now. A diet rich in greens, berries, other fruits and vegetables, beans, nuts and seeds is the only way to ensure that children get the array of phytochemicals, antioxidants, fatty acids and other micronutrients to adequately supply their growing and constantly learning brains. Junk food is not for kids.
1. Otsuka M, Yamaguchi K, Ueki A. Similarities and differences between Alzheimer's disease and vascular dementia from the viewpoint of nutrition. Ann N Y Acad Sci 2002;977:155-161.
2. Morris MC, Evans DA, Bienias JL, et al. Dietary fats and the risk of incident Alzheimer disease. Arch Neurol 2003;60:194-200.
3. Joseph JA, Shukitt-Hale B, Willis LM. Grape juice, berries, and walnuts affect brain aging and behavior. J Nutr 2009;139:1813S-1817S.
4. Devore EE, Kang JH, Breteler MM, et al. Dietary intakes of berries and flavonoids in relation to cognitive decline. Ann Neurol 2012.
5. University of Southern California: U.S. Education Spending and Performance vs. the World. [Infographic]. http://rossieronline.usc.edu/.edu/u-s-education-versus-the-world-infographic/. Accessed October 12, 2012.
6. Gale CR, Martyn CN, Marriott LD, et al. Dietary patterns in infancy and cognitive and neuropsychological function in childhood. J Child Psychol Psychiatry 2009;50:816-823.
7. Smithers LG, Golley RK, Mittinty MN, et al. Dietary patterns at 6, 15 and 24 months of age are associated with IQ at 8 years of age. Eur J Epidemiol 2012;27:525-535.
8. May AL, Kuklina EV, Yoon PW. Prevalence of Cardiovascular Disease Risk Factors Among US Adolescents, 1999-2008. Pediatrics 2012;129:1035.
9. Yau PL, Castro MG, Tagani A, et al. Obesity and metabolic syndrome and functional and structural brain impairments in adolescence. Pediatrics 2012;130:e856-864.