In the study, 16,737 participants were assessed from a population-based cohort in the Singapore Chinese Health Study. To record the intake of nuts, researchers used a validated food-frequency questionnaire from 1993-1998 when the average age of the participants was 53.5 years old. Then the researchers examined the cognitive function through the Singapore modified Mini-Mental State Examination during a follow-up visit from 2014-2016. This meant the participants now had an average age of 73.2 years. Cognitive impairment was defined as using education-specific cut-off points.
At the conclusion of the study, 14.3% of the participants were identified to have a cognitive impairment. It was discovered that those who ate 1-3 servings of nuts per month, 1 serving of nuts a week, and more than 2 servings of nuts a week had a 12% lower risk of cognitive impairment. The authors also discovered that 50.8% of the association between nuts and risk of cognitive impairment was mediated by the consumption of total unsaturated fatty acids. Overall, increasing consumption of nuts in midlife may lead to a lower risk of cognitive impairment later on in life.
Jiang, Y. W., Sheng, L. T., Feng, L., Pan, A., & Koh, W. P. (2020). Consumption of dietary nuts in midlife and risk of cognitive impairment in late-life: the Singapore Chinese Health Study. Age and Ageing.