Tired of hearing about Vitamin D? This much-talked-about topic was heralded by the New York Times as the “supplement of the decade.” But for all the good D can do for your body (like build strong bones, ward off depression, heart disease and possibly even cancer) the mere fact that people are ditching their sunscreens and risking skin cancer to soak up vitamin D-strong solar rays is particularly worrisome. And despite all the hoopla about vitamin D, the information still seems contradictory and ill D-fined.MORE: Vitamin D and Glowing SkinSo let’s clear up the confusion. Here’s what we can tell you about vitamin D:D stands for DesirableOur bodies actually produce the stuff, but like most things that seem to peter off with age, our body’s ability to churn out vitamin D is one of them. D regulates calcium as well as phosphorous levels in the blood and helps with the body’s absorption of calcium.“One of the greatest misunderstandings is that most Americans get enough vitamin D and don’t need to be concerned about it,” says Walter Willett, M.D., chair of the department of nutrition at Harvard School of Public Health in Boston, Massachusetts. “But the evidence is quite strong that many people will benefit from getting even higher levels of D than what’s currently recommended.”QUIZ: Just How Healthy Are You?How Much Does It Take?In November 2010, The Institute of Medicine (IOM) in Washington D.C. released new guidelines for how much D is necessary daily: 600 IU for those under 70 years-old; 800 IU for those older than that.But not everyone agrees with those digits.“I recommend getting a minimum of 1000 IU units a day,” says Michael Roizen, M.D., YouBeauty co-founder and chief wellness officer at the Cleveland Clinic in Cleveland, Ohio. “Get a blood test to be sure of your levels, especially if you have any question that you might be low.” Why the inflated number? “For most people, their D level should be 50 to 80 nanograms, so if they’re over the age of 50 that requires 2000 IUs of D or more daily to reach. So no matter what age you are, you should be getting at least 1000 IU a day,” says Dr. Roizen.The Sun Is Not The Answer“Sunlight is the main natural source of D, but getting adequate amounts of sun without increasing one’s risk of skin cancer is just too complicated for most people,” says Willett.Roizen agrees that raising D levels from the sun alone isn’t so clear cut. While it’s definitely an efficient (and free!) way to get D, you’d have to show some bare, sunscreen-free skin to direct sun for about 10 to 15 minutes—every, single day. (He notes that skipping the sunscreen on your legs while you’re wearing a sun dress should suffice.) But—and it’s a BIG but—this method of going sunscreenless doesn’t work whenever you darn well please. To trigger enough D production, you’d have to be outside when the sun is at its strongest—between April and October—and during prime skin-scorching hours (12 to 3 pm). Oh, and your address matters too; if you’re north of Atlanta or Los Angeles it’s unlikely you’ll get enough D from the sun alone. Complicated, right?“Creating vitamin D in the skin requires a certain amount of energy,” explains Roizen. “Being outside when most people are—before or after work—is simply not going to get you enough of it.”The other super-obvious red flag of soaking up the sun sans sunscreen: skin cancer.MORE: Skin Cancer & Ethnic SkinThere’s no question that constant ultraviolet exposure both intentional (in a bikini, sprawled on the beach) and incidental (walking to and from your car a gazillion times a day) can lead to DNA abnormalities that cause the formation of tumorous cells. Broad-spectrum sunscreens (which you absolutely should be wearing as it’s the number-one way to prevent skin cancer), shield you from UVB—those rays that cause painful sunburns. But they’re also the same wavelength needed for D-synthesis, which is why most doctors say you might as well get D in pill form and be done with it…Pop A PillThere are only a handful of foods that naturally contain D and they aren’t the ones you’d snack on daily—think salmon, swordfish, sardines. “Vitamin D is naturally present in only a few foods; fish being the most important, but the amounts are too low to make much difference,” says Dr. Willett.MORE: Beauty Foods Rich in Vitamin DMilk (both regular and soy), yogurt and some cereals are fortified with the vitamin, but in far smaller percentages than you’d get from fish. Then just think how much milk you’d have to chug to get ample amounts.Both Roizen and Willett recommend consuming the aforementioned D-laced foods whenever possible, but point to pills as your safest bet to amp up D levels. “Vitamin D3 is created in the body and activated by the sun or added to foods, but it’s also the same version you get from supplements,” explains Roizen.So, while research is ongoing on as to the clear amount of D we should each strive for, “I think it makes sense for most people to take 1000 or 2000 IU’s of vitamin D per day as a supplement,” says Willet who suspects we’ll eventually being seeing modified vitamin D recommendations as scientific evidence accumulates. “There’s a strong suggestion that people with darker skin may even need up to 4000 IU’s per day,” he says.And a little insider tip: “There’s data that shows taking vitamin D with a fat like DHA, omega-3, or just have a little olive oil and bread with it, absorbs better,” notes Roizen.So How Serious Is Our D-ficiency?A 2011 report compiled by the Center for Disease Control and Prevention (CDC) found that one-third of the American population is D deficient. However Roizen, who spends many of his days researching this topic and testing patients at the Cleveland Clinic, is adamant the deficiency levels are higher than what’s been reported. “When we test patients, 89 percent of them have levels below 20 nanograms, which is considered deficient for bone health,” he says. “Meanwhile 50 to 80 nanograms is what we want people to get to for overall health.”Roizen is concerned that if we stick to following the daily intake levels of vitamin D currently recommended by IOM (which he believes are too low), it may be enough to prevent osteoporosis and rickets, but not other health concerns. Several studies allude to healthy vitamin D levels playing a significant role in lowering cardiovascular disease as well as mortality from prostrate cancer and skin cancer. In fact, a 2011 study by researchers at Stanford University School of Medicine found that women with non-melanoma (basal and squamous carcinomas) lesions who took a vitamin D-calcium combo developed 57 percent fewer melanomas than those with similar medical histories who didn’t take the supplements.The Bottom LineThe sun is the natural way to get D but we know that UV rays can, over time, cause cancer. So, instead of skipping the SPF to soak up some sun, simply take a D supplement to ramp up your D levels. Then, you’ll still get to enjoy a little sunshine (the safe way!) while keeping cells stay healthy and actually prevent cancering. It’s a win, win.QUIZ: How Much D Are You Getting?