I've heard a lot recently about vitamin D deficiencies. What is vitamin D and why is it so important? Is it something to ask my doctor about?
Vitamin D is a hot topic in medicine these days. What seems to have moved this subject to the forefront is the realization that vitamin D deficiency is extremely common, and perhaps the norm in certain parts of the country.
Vitamin D is an oil-soluble vitamin important to the health of our bones and muscles. It helps control how much dietary calcium we absorb through the intestines and plays a role in setting the hormone levels that prompt the body to move calcium from our bones to our blood. This helps ensure we have the proper amount of calcium in our blood for things such as muscle strength and heart rhythm control.
Our bodies make vitamin D when sunlight hits our skin. That's why low sunlight exposure in winter months, living in northern latitudes, and spending little time outdoors all increase the risk for vitamin D deficiency. (It's important to note, however, that the benefits of sunblock for prevention of skin disease outweigh its negative effects on vitamin D production.) We also get some vitamin D from our diet. Most of that comes from consuming fortified food (like milk). However, some foods—such as fatty fish—naturally contain vitamin D.
While dietary intake of vitamin D and calcium is important, it's not always enough, so many experts recommend that adults take vitamin D supplements. It's reasonable for healthy persons to take 800 IU to 1000 IU of vitamin D3 without asking their doctor. (Vitamin D3 is the form of the vitamin made in our skin.) People with advanced kidney disease or intestinal malabsorption should consult with their doctor about their vitamin D needs. Meanwhile, breast-fed infants need 400 IU of supplementation daily, as do formula-fed infants who ingest less than one liter a day of formula.
In any case, tell your doctor at every visit about everything you take, including prescription and nonprescription medicines, supplements, and herbals. Parents should check with their pediatrician about supplements and their kids' nutritional needs.
Why is getting enough vitamin D important? Low vitamin D is associated with osteoporosis, a condition in which the bones lose density and strength. All treatments and preventive measures for this condition include maintaining adequate calcium and vitamin D intake. It's also believed that vitamin D deficiency is associated with muscle weakness and increased falls in the elderly.
Another condition related to vitamin D deficiency is rickets, which causes the leg bones of malnourished children to grow abnormally. Now rare in the United States thanks to better nutrition, it's common worldwide. Meanwhile, adults with significant vitamin D deficiency can experience bone softening and tiny "micro fractures" with a condition called osteomalacia.
So eat right, get outdoors and exercise, maybe take a supplement, and keep your doctor informed. That's the prescription for getting enough vitamin D—and staying healthy.
