How much vitamin D is optimal? Nutrition experts have been debating this issue for years.
Epidemiologists in England conducted a prospective study in which they measured blood levels of 25-hydroxyvitamin D in more than 14,000 middle-aged people.
Blood Levels Predict Health Outcomes
During 13 years of follow-up, the researchers found that vitamin D levels predicted subsequent mortality and illness, including respiratory disease, cardiovascular complications and bone fractures. Those with the lowest risk of dying during follow-up were individuals who started the study with blood levels of at least 36 ng/ml.
Although previous studies have hinted that too much vitamin D might be risky, this study turned up no evidence of increased mortality at high concentrations of the vitamin.
[American Journal of Clinical Nutrition, Nov., 2014]
Questions Remain
There are still plenty of controversies in the area of vitamin D. For example, is vitamin D3 superior to vitamin D2 for oral supplementation? Is it better to take a daily dose, or is a larger dose taken weekly or monthly equivalent? And finally, is oral vitamin D really as good as sun exposure in maintaining the many physiological functions this vitamin influences?
Those interested in more information on vitamin D may wish to listen to Show 970: Health News Update on Hydrocodone and Vitamin D.
