Objectives: Previous research has shown that nutrition can influence cognitive abilities in older adults. We examined whether nutritional factors or inflammatory biomarkers moderate the age-cognition association.
Method: Analyses included 1,308 participants (age ≥60) from the National Health and Nutrition Examination Survey III. Macronutrients (% of calories from fat, protein, and carbohydrates), micronutrients/amino acids (blood serum values: Vitamins B12, C, D, E, folate, iron, homocysteine, and β-carotene), and inflammatory biomarkers (serum C-reactive protein, plasma fibrinogen, and serum ferritin) were examined as moderators with cognition. Cognition was measured by six tasks: immediate and delayed story recall, immediate and delayed word memory, digit subtraction, and questions about place/orientation.
Results: Higher values of serum folate were significantly associated with better cognitive scores. Specifically, the interaction between age-cognition and folate indicated the associations of higher age and lower global cognition and lower immediate story recall were weaker in those with higher folate values (p's < .05). A significant interaction between age and plasma fibrinogen indicated that the association between age and worse digit subtraction was stronger with values >3.1 g/L.
Discussion: Folate and fibrinogen were significant moderators between age and cognition. Further research into the relationship between nutrition, inflammation, and cognitive aging is needed.