Objective: To study the relationships between dietary macronutrient intakes and age-related changes in cognitive functions.
Methods: We investigated these associations in the prevalence survey (1992 through 1993) of the Italian Longitudinal Study on Aging (ILSA). The population-based sample of 5,632 subjects of the ILSA, age 65 to 84 years, was identified from the electoral rolls of eight Italian municipalities. In this study, standardized test batteries assessing global cognitive functions (Mini-Mental State Examination [MMSE]), selective attention (Digit Cancellation Test [DCT]), and episodic memory (Babcock Story Recall Test), and a semi-quantitative food frequency questionnaire evaluating macronutrient energy intakes, were performed on 278 nondemented elderly subjects from the randomized cohort of Casamassima, Bari (n = 704).
Results: There was an inverse relationship between monounsaturated fatty acids (MUFAs) energy intake and cognitive decline (MMSE < 24). The effect of education on the odds of having a MMSE score <24 decreased exponentially with the increase of MUFA intakes (over 2,400 kJ; odds ratio, 0.69). Moreover, a significant inverse association was observed between MUFA intakes and DCT score (odds ratio, 0.99). No association was found between nutritional variables and episodic memory.
Conclusions: In an elderly population of Southern Italy with a typical Mediterranean diet, high MUFA intakes appeared to be protective against age-related cognitive decline. Prospective clinical trials are needed to evaluate the impact of specific dietary macronutrient intakes on the age-related changes of cognitive functions.