Low levels of vitamin D may accelerate cognitive decline in older adults, a new study finds… “It remains to be determined whether vitamin D supplementation slows cognitive decline,” the researchers noted. Importantly, they found Hispanic and African-American participants, on average, had significantly lower vitamin D levels when compared to their European American peers… “Deficiency is probably due to some combination of limited sun exposure and low dietary intake,” Dr. Joshua Miller, study co-author and chair of the Department of Nutritional Sciences at Rutgers University, told Medical Daily. “There are genetic polymorphisms that can influence the function of vitamin D within cells.”… First, “about 60 percent or more of the participants were low in vitamin D, either insufficient or outright deficient,” Dr. Joshua Miller, study co-author and chair of the Department of Nutritional Sciences at Rutgers University, said in an interview.