Joshua Miller, professor in the Department of Pathology and Laboratory Medicine at the time when the research was conducted and now professor and chair of the Department of Nutritional Sciences at Rutgers University said, “Independent of race or ethnicity, baseline cognitive abilities and a host of other risk factors, vitamin D insufficiency was associated with significantly faster declines in both episodic memory and executive function performance. But on average, people with low vitamin D declined two to three times as fast as those with adequate vitamin D.”
Recent research suggests that lower levels of vitamin D are directly proportional to a sudden decline in cognitive abilities in older adults. This, in turn, increase their risk for Alzheimer’s disease and dementia. The study was done by researchers at the Rutgers University who said that deficiency of vitamin D in the body can be boosted with supplements.
Earlier research also show a link between low levels of vitamin D in the blood and symptoms of depression. However, research hasn’t yet shown clearly whether low vitamin D levels cause depression, or whether low vitamin D levels develop because someone is depressed.
The research was done in almost 400 racially and ethnically different men and women in Northern California participating in longitudinal research at the Alzheimer’s Disease Center in Sacramento, Calif.
Half of the participants were Caucasian and 50 percent were African-American or Hispanic. Research results are suggestive of the fact that 50 percent of Americans above 65 have low levels of vitamin D. It was also seen that African origin people have the highest chance to be deficient on Vitamin D. Low vitamin D levels are common in older age and this is linked to speedy decline in episodic memory and executive function.
Earlier studies have shown that Vitamin D’s effect on mental health extends beyond depression. Schizophrenia has also been linked with abnormal levels of vitamin D. John McGrath of the University of Queensland in Australia(link is external) studied 424 Danish newborns who developed schizophrenia. He concluded that infants born in winter or spring seasons, when birth mothers have decreased levels of vitamin D, are at an increased risk of developing schizophrenia.
It was seen that over this level, the risk of adverse health effects shoots up, with very high doses (10,000 IU/day or more) leading to significant damage to kidneys and other tissues. The study also revealed that people who are African-American or Hispanic had lower levels of vitamin D than white people. Vitamin D is crucial for its role in maintaining bone health and can be found mostly by sun exposure as well as egg yolks, cheese and fish oil.
Circulating 25-OHD levels can only be measured by blood test, and current guidelines consider adequate levels to be in the range of 20 nanograms per milliliter of serum to 50 ng/mL. Associations were evaluated between vitamin D levels and course of cognitive decline. It was seen that vitamin D levels, on an average, were lower in the dementia group as compared to the mild mental impairment and mentally normal people.
Miller said that till now, there have been no serious researches to find out if taking vitamin D could slow down or prevent memory loss, but he suggested measuring your vitamin D level to see whether you need more vitamin D.
The research was published online in JAMA Neurology, a JAMA Network journal.
Source: Press Release