Vitamin D Deficiency Finally Being Recognized As Increasingly Common

Vitamin D has long been known to play an important role in bone health. Deficiency can lead to osteoporosis in adults, and in children and some adults can lead to a bone-softening disease known as rickets.

Although the vitamin is synthesized by the body upon exposure to sunlight, people living far from the equator can have trouble producing enough of it in the winter time. For this reason, numerous governments began fortifying dairy products with vitamin D decades ago, leading directly to a near-elimination of rickets. The disease is starting to make a resurgence, however, even as researchers start to believe that humans may need higher levels of the vitamin than previously thought.

Although the U.S. government recommends a daily vitamin D intake of 200 to 600 IU per day, researchers are increasingly suggesting amounts of closer to 1,000 IU. These amounts are based on new studies finding that higher levels of vitamin D can help regulate the immune system and prevent chronic diseases such as cancer, heart disease and Alzheimer's.

"It helps boost your ability to fight infection, and it also reduces some destructive inflammation in your body, including inflammation with periodontal disease," said Mark Ryder of the University of California-San Francisco. "Every five or 10 years, a new vitamin becomes the vitamin of the moment. The hot one right now is probably vitamin D, and so far all of the evidence looks encouraging."

Yet even according to the lower government standards, at least one in three U.S. residents are not getting enough vitamin D.

"We've become a culture that shuns the sunshine and doesn't drink milk," said Dr. Donald Abrams of San Francisco General Hospital.