Vitamin D prevents dementia

Vitamin D supplementation has the potential to be a viable dementia prevention strategy, especially when initiated early, new research suggests (Alz Dement Diagn Assess Dis Monit. Published online March 1, 2023.).

In a large prospective cohort study, people who took vitamin D were 40% less likely to develop dementia than peers who did not take vitamin D. The effects of vitamin D were most pronounced in women, those with normal cognitive function, and apolipoprotein E (APOE) ε4 noncarriers.

The findings are based on 12,388 adult participants (mean age, 71 years) in the US National Alzheimer's Coordinating Center database who had normal cognition or mild cognitive impairment (MCI) at the outset. A total of 4637 (37%) took vitamin D supplements, and 7751 did not.

Those who took vitamin D supplements were more likely to be women and to have higher education levels. Depression and MCI were more common in those not taking vitamin D.

Over 10 years, 2696 participants developed dementia, including 2017 (75%) who had no exposure to vitamin D supplements. The 5-year dementia-free survival rate was 84% in vitamin D group, vs 68% in the group that did not take vitamin D.

After adjusting for age, sex, education, race, cognition, depression, and APOE4 status, vitamin D exposure (vs no exposure) was significantly associated with a lower incidence of dementia