Dietary intake and cognitive function: evidence from the Bogalusa Heart Study

Dementia and late-life cognitive decline are leading causes of death and disability in the United States. Prevention of these diseases, by maintaining brain health throughout the life course, is essential. Diet and lifestyle changes are the chief strategies aimed at primary prevention for many of the risk factors of cognitive decline.

The aim of this study was to examine the potential impact of dietary factors on cognitive function.

This prospective cohort study followed 516 young adults through midlife. The Youth/Adolescent Questionnaire was used to collect habitual nutrition data (mean age: 32.03 ± 5.96 y) at baseline. Scores from a neurocognitive battery were used to assess cognitive function (mean age: 49.03 ± 4.86 y) at follow-up and were transformed to z scores. Separate multivariable-adjusted linear regression models were fitted. The trend across quintiles for each dietary variable was assessed.

Vitamin B-6, whole grains, processed meats, and foods fried at home all displayed significant linear trends in their relation with cognitive function. Dietary intake of vitamin B-6 and whole grains was directly associated with better cognitive function after adjustment for age, race, sex, and total calorie intake (β coefficient from linear regression and SE: 1.755 ± 0.621, P = 0.005, and 0.001 ± 0.000, P = 0.018, respectively). Processed meat and foods fried at home consistently displayed inverse associations with cognitive function across crude and adjusted models (linear trend P values were 0.05 and <0.0001, respectively).

Our findings suggest that dietary consumption in young adulthood may affect cognitive function in midlife. Strong associations between dietary intake and cognition were observed in our analysis, but as with all observational studies, the possibility of residual confounding cannot be excluded.