Daily Nut Consumption May Help Prevent Dementia and Disability in Older Adults

Daily nut consumption is associated with the prevention of the onset of dementia and disability in older adults, particularly for those with suboptimal dietary quality, according to study findings published in Age and Ageing.

The association between nut consumption and leading a disability-free life in older age remains uncertain. To explore this further, researchers set out to investigate the relationship between nut intake and disability-free survival among older adults.

The researchers conducted a prospective cohort study using data from 9916 community-dwelling adults aged 70 years and older. Participants were enrolled in the ASPREE Longitudinal Study of Older Persons and were free from dementia, major physical disabilities, and cardiovascular disease at baseline. Nut consumption was assessed through a 49-item food frequency questionnaire, categorizing participants into 3 groups based on intake: no/infrequent (less than twice per month), weekly (1 to 6 times per week), and daily (once or more per day).

The primary outcome was disability-free survival, defined as survival without the onset of dementia, persistent physical disability, or mortality. Researchers employed Cox proportional hazards regression models to analyze the association between nut consumption and disability-free survival, adjusting for variables such as age, gender, socioeconomic status, physical ability, and overall diet quality.

During an average follow-up period of 3.9 years, a total of 997 composite outcome events occurred, of which 63.8% were in men.Compared with individuals who consumed nuts infrequently, those who consumed nuts daily had a 23% lower risk of reaching the study’s endpoint (hazard ratio [HR], 0.77; 95% CI, 0.61-0.98). Subgroup analysis demonstrated an even stronger benefit among those with moderate dietary quality, where daily nut consumption was associated with a 29% reduced risk of the composite outcome (HR, 0.71; 95% CI, 0.51-0.98).

Compared with individuals who infrequently consumed nuts, those who consumed nuts daily demonstrated healthier baseline characteristics. These participants were more likely to report higher physical activity levels, better oral health, lower frailty scores, and adherence to dietary guidelines.

Study limitations included reliance on self-reported nut consumption, lack of detail on nut types or amounts, and a homogenous study group of older, independent Australians, which may limit broader generalizability.

“…[T]he findings of our study suggest that daily nut consumption is associated with an improved healthy lifespan in older adults, including in those whose diet quality may not be optimal,” the researchers concluded.

This research was supported by the National Institute on Ageing, the National Cancer Institute, the National Health and Medical Research Council of Australia, Monash University, the Victorian Cancer Agency, and additional collaborators listed on the ASPREE website. One study author declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of disclosures.