Vitamin D derailed

In old Vienna, which was a world center of medicine during the era of Sigmund Freud, it was said that the doorman at the medical center decided which treatment patients received for ulcers. If he pointed you to the surgeon, you got a stomach operation. If he pointed you toward the internist, you got a prescription for diet, stress reduction, and drugs.

Today, it seems that whether or not you should take vitamin D supplements follows the same sort of “logic.”

Of course, the best way for humans to get most of their active vitamin D is from the sun. Unfortunately, due to irresponsible recommendations for sunscreens and sun avoidance, most people never get enough sunlight. And there are only few food sources rich in vitamin D. Mostly fatty fish, which most Americans don’t eat much of. Thus, the most knowledgeable doctors and scientists recommend supplementation.

But two years ago, the U.S. Institute of Medicine (IOM) revised the recommendations for vitamin D levels from 30 nanograms/milliliter to 20 ng/ml. The last I checked, the distinguished members of the IOM weren’t selected for their knowledge or understanding of nutritional medicine or natural approaches. And the science bureaucrats who run their reviews know even less about anything.

Yet, with a simple stroke of a pen, the IOM appears to have “solved” one of the biggest nutritional deficiencies of modern times. Researchers at Loyola University Chicago Stritch School of Medicine have thus calculated that 79 million adults once considered to have insufficient vitamin D now have sufficient levels under the new guidelines.

And now another new study published recently in the Canadian Medical Association Journal has added more fodder to the Great Vitamin D Debate.

Researchers concluded that people with a genetic tendency to live longer actually have lower vitamin D levels. Of course, this observation is being generalized to cast doubt on the benefits of vitamin D for everyone.

But these researchers simply showed that there is a gene for living longer—and older people who have this gene have lower vitamin D levels. All this proves is that the “anti-aging gene” makes the lucky people who have it indeed live longer—and they don’t need higher levels of vitamin D to get there.

But what about people who don’t have this special longevity gene? Maybe when they live to old age it’s because they do have higher vitamin D levels.

My friend, Dr. Walter Willett, a respected nutritionist at Harvard School of Public Health in Boston, has said the IOM guidelines for vitamin D blood levels are too low. Willett cites two large studies from 2009 demonstrating that the 20 ng/ml level is too low even to prevent bone fractures from falls. Let alone the other non-bone benefits associated with adequate vitamin D levels.

And even the authors of the recent Canadian study admit that “low serum levels of 25-hydroxyvitamin D3 (25[OH] vitamin D) are associated with increased mortality, cardiovascular disease, diabetes mellitus, cancer, multiple sclerosis, allergy, asthma, infection, depression, mental illness and musculoskeletal pain.”

The fact is, those of us who don’t have special longevity genes need to pay more attention to our vitamin D intake. For some specific recommendations on how to achieve and maintain optimal levels, refer to the article “There goes the sun,” which appeared in the October 2012 issue of my Insiders’ Cures newsletter.

“Levels of 25-hydroxyvitamin D in familial longevity: the Leiden Longevity Study,” Canadian Medical Association Journal 2012; Nov 5 (epub ahead of print )