Low vitamin D levels may be linked to increased all-cause mortality, particularly in older adults. Observational studies have shown a general trend for associations between low vitamin D levels and all-cause mortality in general[1] and elderly[2] populations.
The link between increased all-cause mortality and low vitamin D levels in elderly participants has been confirmed by clinical trials showing decreased mortality with vitamin D3 supplementation.[3]
Although associations between low vitamin D levels and increased all-cause mortality in the general population have been reported in observational studies,[1] randomized controlled trials with adult participants 18 years or older have failed to confirm this, finding no evidence for an association between vitamin D supplementation and all-cause mortality compared to a placebo.[4]
More research is needed to better understand the influence of vitamin D supplementation on all-cause mortality and longevity in different populations.