- Researchers assessed the association between vitamin D supplementation and the incidence of dementia.
- They found that vitamin D supplementation was linked to a lower dementia incidence.
- Further studies are needed to certify the results.
Over 55 million people live with dementia worldwide, which is expected to rise to
Interventions that can affect dementia risk factors are being explored to slow disease progression. One such risk factor is vitamin D deficiency.
Some studies have found that vitamin D may aid the clearance of amyloid beta aggregates—one of the hallmarks of Alzheimer’s disease (AD). However, studies have produced conflicting results on whether vitamin D improves cognitive function.
Further studying the link between vitamin D supplementation and cognitive decline could help develop preventative strategies for dementia.
Recently, researchers assessed the link between vitamin D supplementation and incident dementia. They found that vitamin D supplementation is linked to lower incidence of dementia.
The study was published in
For the study, the researchers analyzed data from 12,388 people from the National Alzheimer’s Coordinating Center, who were dementia-free at the start of the study. Their average age was 71 years old.
Altogether, 37% of the cohort took at least one of three vitamin D supplements: calcium-vitamin D, cholecalciferol, and ergocalciferol.
In their analyses, the researchers also accounted for demographic, clinical, and genetic variables, such as depression and APOE ε4 status—a gene variant linked to a higher risk of dementia.
After five years, the researchers found that 83.6% of those exposed to vitamin D supplements were alive and dementia-free. The same was true for 68.4% of those not exposed to vitamin D.
Within 10 years, the researchers found that 22% of participants developed dementia, of which 74.8% were not exposed to vitamin D supplements.
Whereas 14.6% of those with vitamin D exposure progressed to dementia, the same was true for 26% of those with no vitamin D exposure.
After adjusting for factors including cognitive diagnosis, depression, and APOE ε4 status, they found that vitamin D exposure was linked to a 40% lower incidence of dementia compared to no exposure.
Women see more benefit
The effects were strongest among women: women exposed to vitamin D were 49% less likely to develop dementia than those without exposure. Vitamin D-exposed men were 26% less likely to develop dementia than non-exposed men.
The researchers also found that depression was linked to a 35% higher incidence of dementia.
While findings were consistent for each vitamin D formulation, they noted that vitamin D supplements had the greatest effects on individuals with normal cognition as opposed to mild cognitive impairment and APOE ε4 non-carriers versus carriers.