Low levels of Vitamin D may cause earlier cognitive decline among the elderly.
Few studies have examined the association between vitamin D and cognitive decline or dementia. To look into this association, researchers from the UK studied the cognitive function of 858 Italians aged 65 years and older. The participants completed interviews, cognitive assessments, and medical examinations and provided blood samples twice during the follow-up period of six years.
It was found that those who had deficient levels of vitamin D in their blood (<25 nmol/L) were almost twice scored lower on the questionnaires judging cognitive function than those who had sufficient levels of vitamin D in their blood (75 nmol/L). In comparison to those with healthy levels of vitamin D, people with severely deficient levels were 60% more likely to experience substantial mental decline.