Everything you need know about vitamin D deficiency and how to get more of the micronutrient.

Scattered vitamin D3 capsules in the sunshine on a white painted wood surface.
Credit: Rosemary Calvert/Getty Images

If you keep up with nutrition research, then you probably heard about a recent major study suggesting that taking vitamin D supplements doesn't lower cancer or heart disease risk. In the 25,871-person study published in the New England Journal of Medicine, participants who supplemented with a vitamin D pill for roughly five years weren't significantly less likely to have cancer or heart issues compared to a placebo group. Womp.

But that doesn't mean you should ignore your vitamin D intake. It's still widely considered one of the most scientifically-proven keys to bone health. And there's a good chance you you're not getting enough–vitamin D deficiency consistently comes up as one of the most common nutrient deficiencies in the U.S.

One factor that might contribute to the common deficiency is that few foods are high in vitamin D. Fatty fish like salmon and trout are some of the highest sources of vitamin D, and egg yolks and mushrooms also contain small amounts. In the U.S., foods like milk, cereal, and orange juice often get fortified with vitamin D. Direct sunlight is the preferred source of vitamin D, but carries the risks associated with UV exposure, says Dr. Richard Firshein, D.O., Founder of Firshein Center for Integrative Medicine. Your body can generate vitamin D when sunlight hits your skin.  Supplements, a third option, are a great option for people who don't get a lot of vitamin D through their diet, Dr. Firshein says. (Related: High Vitamin D Levels Linked to Increased Risk of Death)

You should be concerned about low vitamin D levels, even if your current age puts you at low common bone-related conditions. "Most studies suggest that getting Vitamin D in your teenage years is important for bone growth in development," Dr. Firshein says. "Not getting enough vitamin D in your teenage years appears to put you at increased risk for osteoporosis, which is the cause of weakened bones that break over time."

In addition to its role in bone formation, vitamin D impacts neuromuscular and immune function and keeps inflammation at bay, according to the National Institutes of Health. The nutrient might play a role in preventing cancer, hypertension, multiple sclerosis, and other conditions, but we need more research to know for sure, according to the government agency. Because of its anti-inflammatory powers, vitamin D supplementation might have potential for treating the symptoms of inflammatory conditions like inflammatory bowel disease and psoriasis. (Related: Could Vitamin Deficiencies Be Ruining Your Workout?)

Long story short, vitamin D is considered to be critical for bone health and might also lead to other health benefits. Checking in with your doctor for a lab test is the best way to find out where you stand, and potentially get a new excuse to eat more salmon.