Wednesday, April 2, 2014

Low Vitamin D Levels Linked to Disease in Two Big Studies

People with low vitamin D levels are more likely to die from cancer and heart disease and to suffer from other illnesses, scientists reported in two large studies published on Tuesday.

The new research suggests strongly that blood levels of vitamin D are a good barometer of overall health. But it does not resolve the question of whether low levels are a cause of disease or simply an indicator of behaviors that contribute to poor health, like a sedentary lifestyle, smoking and a diet heavy in processed and unhealthful foods.

Nicknamed the sunshine nutrient, vitamin D is produced in the body when the skin is exposed to sunlight. It can be obtained from a small assortment of foods, including fish, eggs, fortified dairy products and organ meats, and vegetables like mushrooms and kale. And blood levels of it can be lowered by smoking, obesity and inflammation.

Vitamin D helps the body absorb calcium and is an important part of the immune system. Receptors for the vitamin and related enzymes are found throughout cells and tissues of the body, suggesting it may be vital to many physiological functions, said Dr. Oscar H. Franco, a professor of preventive medicine at Erasmus Medical Center in the Netherlands and an author of one of the new studies, which appeared in the journal BMJ.

“It has effects at the genetic level, and it affects cardiovascular health and bone health,” he said. “There are different hypotheses for the factors that vitamin D regulates, from genes to inflammation. That’s the reason vitamin D seems so promising.”

The two studies were meta-analyses that included data on more than a million people. They included observational findings on the relationship between disease and blood levels of vitamin D. The researchers also reviewed evidence from randomized controlled trials — the gold standard in scientific research — that assessed whether taking vitamin D daily was beneficial.  (...)

“We are talking about a large part of the population being affected by this,” he said. “Vitamin D could be a good route to prevent mortality from cardiovascular disease and other causes of mortality.”

by Anahad O'Connor, NY Times |  Read more:
Image: Lawrence Lool/European Pressphoto Agency