Vitamin D supplementation is associated with a 40% reduction in the risk of dementia over a decade.

noli's read

This advice is based on an observational study published in 'Alzheimer's & Dementia' (2023) involving over 12,000 participants. It is important to note that, as an observational study, it shows a correlation but does not prove a direct causal link: it is possible that individuals taking vitamin D generally lead healthier lifestyles. Current research, particularly via meta-analyses of randomized controlled trials (RCTs), remains nuanced and suggests that while adequate levels of vitamin D are essential for brain health, the protective effect of systematic supplementation in non-deficient individuals is not yet firmly established. The statement is therefore faithful to the data from the cited study, but the 40% figure must be interpreted with caution as it comes from a specific context and not from universal clinical proof. Other factors, such as physical activity and sun exposure, likely play confounding roles in these results. In summary, vitamin D is a pillar of metabolic health, but it should not be viewed as an isolated miracle shield against cognitive decline.

the sources

No named source held this one up — that absence is part of the verdict.