Yahoo Lifestyle Low Vitamin D Doubles Your Risk For Dementia
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There was already a pile of research connecting low vitamin D levels with higher rates of dementia.
Now, a large long-term study from the journal Neurology strengthens those links between the "sunshine vitamin" and one of the most common and crippling age-related brain diseases.
The study team measured the vitamin D levels of nearly 1,700 adults and kept tabs on their health for more than five years. Those with low D were 53 per cent more likely to develop dementia than people with normal levels, the study authors found. People who tested low on the vitamin were also about 70 per cent more likely to suffer from Alzheimer's disease — the most common form of dementia.
Those risk factors ballooned even higher among people with "severe" vitamin D deficiencies. According to the study, those who tested lowest for D were 125 per cent more likely to develop dementia than those who had adequate levels.
The study authors said they were somewhat surprised by the findings. Although they'd expected to find an association between low D and higher rates of dementia, the association was twice as strong as they'd anticipated, says study author David Llewellyn, PhD, of the University of Exeter Medical School in the UK.
What does D have to do with dementia? "Vitamin D may help with the breakdown and clearance of Alzheimer's disease markers," Llewellyn explains—although he says this information is based on laboratory and animal studies. When it comes to people, it's not yet clear whether the same mechanisms are at work. For that reason, Llewellyn says it's premature to recommend loading up on vitamin D supplements. (Research on those supplements has been mixed, with some studies indicating that low D may be a symptom of poor health—not a cause.)
Until health experts figure out the details of the vitamin D-dementia connections, Llewellyn advises getting more D from diet and time spent out doors. Oily fish (like salmon) and sun exposure are two natural sources of vitamin D, he says. D-fortified milk (or soymilk) and eggs are some other solid dietary sources. Llewellyn also recommends plenty of exercise — a proven dementia-blocker.
