7 Signs You May Have A Vitamin D Deficiency

With the Polar Vortex now firmly in our past, we're ready to shed some layers and soak up some springtime sun.

About time, too, considering it's our greatest source of vitamin D, a nutrient crucial to bone, skin and mental health. In fact, about 80 to 90 percent of our vitamin D comes from sun exposure, says Dr. Michael F. Holick, M.D., Ph.D., a professor of medicine, physiology and biophysics at the Boston University Medical Center who has studied and published on vitamin D for decades. "The problem is [many of us] assume if you have a healthy diet that you're getting enough of every nutrient," he says. Even the best dietary sources of vitamin D aren't loaded with the nutrient: a serving of salmon is a good bet, with around 450 International Units (IU) of vitamin D per three ounces, according to the National Institutes of Health Office of Dietary Supplements. But there are just 137 IUs per serving of fortified OJ and around 120 in fortified milk.

The Institutes of Medicine recommend most children and adults under age 70 get 600 IUs of vitamin D daily, and those over 70 should aim for 800. But Holick, working with an Endocrine Society committee, found that up to 1,000 IUs a day for children and 1,500 to 2,000 IUs a day for adults was safe and effective, he says. (These recommendations are also well within the safe upper limits set by the IOM).

Without enough sunlight and dietary D, children may be at greater risk for rickets, a softening of the bones, and adults may be at greater risk for osteoporosis. Vitamin D deficiency may also up risk of high blood pressure and type 2 diabetes, says Holick...