New Jersey – According to a recent study , published in JAMA Neurology, low Vitamin D levels are associated with Alzheimer, cognitive decline and dementia. Other disorders, like osteoporosis, cancer, muscle weakness, heart disease and asthma in children are associated with the low levels of this vitamin as well.

Joshua W. Miller, PhD, of Rutgers University in New Brunswick, NJ, and co-authors from the University of California-Davis, examined 382 ethnically diverse older adults (age average of 75,5) -enrolled from an outpatient clinic in California between February 2000 and August 2010-, to see if there was any association between vitamin D status and changes in their cognitive function.

VitaminD-dementia
Credit: The Independent

The team found that there is actually a direct association between both factors. The study showed that those who exhibit a high prevalence of vitamin D insufficiency or deficiency showed and accelerated decline in cognitive function domains two to three times faster than those with adequate vitamin D levels. However, it is not clear if vitamin D supplementation could slow cognitive decline.

“We were not particularly surprised by our findings because there is a recent and growing literature on the associations between vitamin D status and risk of Alzheimer’s disease/dementia, cognitive decline, and brain atrophy,” said Miller to Reuters Health.

The study also found that ethnic groups with darker skin are less able to absorb vitamin D from sunlight, so they are three times more likely to have vitamin D deficiency than light-skin-color people.

“This is a vitamin deficiency that could easily be treated and that has other health consequences. We need to start talking about it. And we need to start talking about it, particularly for people of color, for whom vitamin D deficiency appears to present an even greater risk,” said Charles DeCarli, director of the Alzheimer’s Disease Center, in a release.

In the US, vitamin D low levels are common in older people. What causes this deficiency is limited exposure to sunlight, darker skin color and not eating the recommended levels of the vitamin in foods like fish and egg yolks. “Insufficiency” is classified as 25-OHD blood levels between 12-20 ng/mL, and “deficiency” is less than 12 ng/mL.

According to the study, the National Health and Nutrition Examination Survey found that 42% of the general adult population had deficiency and insufficiency of vitamin D, with even higher prevalence among Hispanic (69%) and African American (82%) individuals.

Source: JAMA Neurology