Deficient is not a word we like to hear used to describe us. Unfortunately, that’s what most of us are — in vitamin D, that is. It's estimated that three out of four Americans are D-deficient. Yet, how to get the needed vitamin — and exactly how much of it — is up for debate. That's why we scoped out the true lowdown on D.
“Although our body doesn’t make vitamin D on its own, it does create the precursor to it, referred to as vitamin D2," says Jeffrey Morrison, M.D., founder of The Morrison Center in New York City. "Then, when we get ultraviolet exposure, that precursor is converted to the active form of vitamin D, which is vitamin D3.”
Morrison says that low vitamin D levels can cause some autoimmune-related diseases such as fibromyalgia as well as seborrheic dermatitis. And, studies show that pregnant women who had low D put their children at risk for asthma and type-1 diabetes. Plus, low D has been linked to an increase in seasonal affective disorder (SAD).
The only way to truly know if you are D-ficient is to get a blood test. The healthy range of D, number-wise, is broad because your body's specific needs depend on a number of factors. However, if your results fall anywhere above 32, you’re fine in terms from a baseline health perspective. Still, Morrison notes that he prefers to see the number hit 50 to 100, as that’s the optimal range for disease prevention.
So, that brings us to the big controversy around D — namely, the sun. Because for the body to create active vitamin D3, the skin needs to come in contact with sunscreen-free UV light, and the sun’s rays, are of course, a known carcinogen that has been linked to skin cancer. While some experts say that all you need (on an average day) is about 10 minutes in the sun, others say if you were to add those 10 minutes up over your lifetime, it could be enough UV light to lead to skin cancer.
Theoretically, you’re probably getting enough incidental sun exposure, and that it could be enough to get enough D. But, the statistics suggest otherwise, because most of us are still low. Enter: fortified foods...right?
Unfortunately, outside of cod liver oil, there aren't that many foods that naturally contain vitamin D3. Some foods, such as orange juice and most cereals, have had D added to them. Just be sure it isn’t laced with the cheaper and subpar precursor D2, which is harder for your body to convert.
Another no-brainer way to get D, which many experts say is the safest, is taking a supplement. “It can be very difficult to get ample D from sun exposure alone,” says Morrison, who notes the standard recommendation on D is about 400 international units (IU). However, he normally recommends around 1000 IU daily for those who aren’t at risk or have any health conditions related to low D — then it could go up to even 5000 IU. And, because vitamin D is a fat-soluble vitamin, it’s better absorbed by the body when taken along with a fat-based food, such as yogurt or a salad with olive oil dressing.
Bottom line: Go to your doctor to get a blood test to know where your levels stand. Then, ask her to recommend a daily supplement amount to be sure you get all the D you need. Finally, don't be afraid to let the sun shine in — just a little bit.