Over the last year, three studies centering around the benefits of Vitamin D have been accepted by The Journals of Gerontology. The separate studies focused, respectively, on: the relationship between vitamin D intake and cognitive decline in women over the age of 75; low levels of vitamin D contributing to cognitive impairment in community dwelling elderly women; and the association between low levels of vitamin D and the onset of mobility limitation and disability in community dwelling elderly men and women called The Health ABC study.
In the first aforementioned study, the objective was to determine whether the dietary intake of vitamin D was an independent predictor of the onset of dementia within 7 years among women aged 75 years and older. 498 women from 75 to 83, free from vitamin D supplements, were placed into three groups: no dementia, Alzheimer's Disease (AD), and other dementias. The researchers then estimated base vitamin D dietary intake via a "self-administered food frequency questionnaire." Other factors considered in the study included sun exposure, education levels, chronic diseases, physical activity and the use of psychoactive drugs. The good news is that a higher dietary intake of vitamin D meant a lower risk of developing AD, however, the study also showed that there were no differences found on other forms of dementia relating to vitamin D dietary intake.
In the next study, focusing on cognitive decline in community dwelling women (6,257 participants over the span of four years), the authors studied the hypothesis that lower vitamin D levels were associated with both cognitive impairment and the risk of cognitive decline. Their conclusion was that lower levels of D meant higher odds of impairment and decline. Though not all patients with cognitive impairment go on to develop AD, almost all AD cases begin with mild cognitive impairment. Another good case for making sure that the elderly women in our lives are getting enough of this crucial supplement, the sooner the better.
The findings of The Health ABC study apply to senior men as well as women. The study spanned six years with biannual evaluations of black and white, initially well-functioning male and female community dwelling residents. The evaluations detected any difficulty walking a 1/4 mile or going up ten steps "using Cox proportional hazard regression models adjusted for demographics, season, behavioral characteristics, and chronic conditions." The conclusion: if low levels of vitamin D are prevented, mobility disabilities in older adults can be reduced.