We’ve heard a lot about antioxidants and their beneficial effects on the body, but evidence on the potency of vitamin D is fast catching up. Dr. Theresa Knight, an OB-Gyn at Women’s Health Specialists of St. Louis, says D is technically not a vitamin because vitamins, by definition, are something we need to take in from our environment, and the body makes its own vitamin D. But she says doctors are seeing a lot more vitamin D deficiency in the general population. “One study in Boston showed that during the winter, 36 percent of women between the ages of 18 and 30 had deficiencies. In the summer that number was only 8 percent. So lack of sun exposure is a culprit,” Knight says. She adds that bowel disorders such as celiac and Crohn’s disease, as well as gastric bypasses for weight loss, all cause malabsorption of fat and fat-soluble vitamins. Liver and kidney disease also affect vitamin D levels.
Knight says the literature increasingly shows that vitamin D is an essential part of metabolism, not just for bone health, but for our whole immune system. “We have vitamin D receptors and enzymes that help us metabolize it. Some people may be born with fewer receptors or can’t metabolize it,” she says. Patients who test low (below 30) for vitamin D are put on D-3 supplements of 2000 i.u. (international units) a day. In addition to supplementation, Knight recommends a diet containing fatty fish, fortified milk, eggs, and some high-D plant sources.
Cheryl Shea, a chiropractor with Complete Wellness Center, says she finds vitamin D so important, she put people on D this year instead of recommending flu shots. “A Japanese study indicated it was more effective, and more literature ties deficiencies with a host of ailments,” she notes, adding that studies showing an increase in multiple sclerosis (MS) in northern climates, along with lower vitamin D, prompted researchers to look at vitamin D deficiencies and other autoimmune diseases (lupus, rheumatoid arthritis, most hypothyroidism)—even cancer. “Vitamin D deficiencies may be involved in breast and other cancers,” she says.
Shea usually tests for vitamin D levels and considers multiple reasons, besides sun exposure, for deficits. “Increased levels of cortisol, the stress hormone, deplete vitamin D, and gastrointestinal disorders prevent its absorption,” she explains. “In many ways, vitamin D acts like a hormone, so imbalances of other hormones, like estrogen, testosterone, insulin, and thyroid seem to be linked.” For supplementation, Shea likes an emulsified liquid of vitamin D-3. One drop on the tongue daily gives 2,000 i.u. “The vitamin D council recommends an intake of 4,000 to 10,000 i.u. per day,” she notes.
St. Luke’s Hospital internal medicine specialist Dr. Christina Skale says that in some ways, vitamin D is the new cholesterol. “We’re finding that it’s more important in multiple diseases than we realized,” she says. “I call people back for vitamin D deficiency more than any other lab result.” One of the reasons she thinks D deficiency has far-ranging implications is that African-Americans have more deficiency but relatively low rates of osteoporosis. Their cardiovascular disease rates, however, are higher.
Skale says it’s ideal for D blood levels to be above 45. There has been no data generated that high levels of vitamin D are in any way harmful. “The most common symptom I see with D deficiency is fatigue,” she says. “I supplement deficient patients with high amounts: a 50,000 i.u. pill once a week for eight weeks. Frequently, they come back at the end of eight weeks and say their fatigue went away, as did joint or bone pain.”
So after eight weeks of intense therapy, we’re good to go, right? Not so fast, says Skale. After levels are brought to normal, she puts her patients, men and women, on calcium with D supplements for life. “I want them to take 1,500 mg of calcium and 1,000 i.u. of vitamin D a day,” she says. “If they were deficient, and they go back to what they were doing, their levels will fall. I want them to be in good health and stay there.”