BOSTON—The association between nutrient intake and cognition may vary with gender, according to a study presented at the 2013 Alzheimer’s Association International Conference. High overall intake of energy appears to be associated with better cognition among men, and a high proportion of energy from fat may be associated with better cognition among women, said Jenni Lehtisalo, MSc, researcher at the National Institute for Health and Welfare in Helsinki. A high proportion of energy from carbohydrates, however, may be associated with poor cognitive performance in both sexes.
Overall, study participants in the highest tertile of vitamin E intake, vitamin D intake, or folate intake had better cognitive performance than subjects in the lowest tertile of intake of these nutrients, said Ms. Lehtisalo. When analyzed by gender, the associations between vitamin E intake and cognition and folate intake and cognition were only significant among men, however. The association between vitamin D intake and cognition was only significant among women. Different patterns of nutrient intake may partially explain the gender-related differences.
Investigators Examined Data From an Ongoing Geriatric Trial
Ms. Lehtisalo and colleagues examined dietary data for 1,235 participants (578 women) in the Finnish Geriatric Intervention Study to Prevent Cognitive Impairment and Disability, an ongoing, randomized controlled trial. Participants’ mean age was approximately 69, and their mean Mini-Mental State Exam score was approximately 27.
The investigators administered a neuropsychologic test battery to all subjects and calculated a composite z score from 12 tests assessing memory, executive function, and processing speed. Dietary intake was evaluated with three-day food records and calculated as a percentage of energy for macronutrients and as a mean daily intake for micronutrients.
Subjects Had Inadequate Folate Intake Subjects’ mean dietary intakes of various nutrients, with the exception of folate, were adequate. Mean energy intake was 8.5 MJ for men and 6.7 MJ for women. The percentage of energy derived from fat was 34.0 for men and 33.1 for women. Mean vitamin D intake was 14.2 µg/day for men and 13.6 µg/day for women. Mean folate intake was 279 µg/day for men and 259 µg/day for women.
“There is relatively a lot of data linking dietary factors and cognition, but the direction of these associations is not clear yet,” Ms. Lehtisalo told Neurology Reviews. “Most of the dietary factors associated with better cognitive functions or lower risk of dementia are already known to be beneficial in the prevention of other chronic diseases, such as cardiovascular disease or diabetes, even if the data on prevention of dementia or cognitive decline are somewhat less consistent.
“The main advantage of our study is the detailed data on the dietary intake and cognition,” she continued. “However, the cross-sectional setting is not optimal, but this was only the baseline of our study, which is ongoing. Next spring, our two-year intervention will be finished, and we’ll hopefully be able to say more about how nutrition and other lifestyle changes such as exercise and cognitive training affect cognitive functions in a clinical trial.”
—Erik Greb
Senior Associate Editor