Vitamin D is an essential nutrient for our health, but oftentimes, it’s misunderstood. Perhaps you’ve seen eye-catching ads on social media that try to persuade you to take vitamin D supplements in the name of “self-care,” or maybe your health-conscious friend just implored you to get your vitamin D levels checked because you don’t spend a ton of time in the sun. Either way, the actual role of vitamin D in your health tends to get lost in the shuffle.
In the simplest terms, vitamin D helps regulate the amount of calcium and phosphate in the body, keeping your bones, teeth, and muscles healthy. When you don’t have enough vitamin D, you run the risk of developing bone health issues such as osteoporosis. Other long-term side effects of vitamin D deficiency can include the development of certain heart conditions, cancers, high blood pressure, diabetes, immune system disorders, and more.
Generally speaking, it’s recommended that adults get between 600 and 800 international units (IU) of vitamin D per day from a combination of sources, including diet, sun exposure, and, in some cases, supplements.
However, everyone needs varying amounts of vitamin D depending on factors such as age, weight, health background, and skin type, says Rachel Nazarian, MD, FAAD, a dermatologist based in New York City. For instance, she explains, the health of your liver and kidneys—where vitamin D is converted into an active hormone that your body can use to promote calcium absorption—can affect your body’s ability to absorb the nutrient.
Your vitamin D needs might also be influenced by what your diet currently looks like, adds Dr. Nazarian. “People who don’t get sufficient vitamin D from daily nutrition, such as those who avoid dairy or other calcium-based products, may need to supplement more,” she explains.
Obviously, you can (and should) get vitamin D from the sun as well. But achieving healthy vitamin D levels doesn’t have to mean increasing your sun exposure and, therefore, your risk of sun damage. Below, experts debunk some of the most common myths about vitamin D and sun protection.
1. The More Vitamin D You Get, the Better
Perhaps you’ve always thought that the more vitamin D you get, the stronger your bones will be and the more metabolic health issues you’ll avoid in the long run. But, in reality, it’s absolutely possible to have too much vitamin D.
For example, while vitamin D does play an important role in blood pressure regulation, too much can lead to high calcium levels, which can cause calcium deposits to form on blood vessel walls and actually increase your risk of heart health issues.
In medical terms, excessive amounts of vitamin D in the body is known as vitamin D toxicity, or hypervitaminosis D. According to the Mayo Clinic, vitamin D toxicity is usually caused by large doses of supplements, rather than diet or sun exposure. Short-term symptoms of too much vitamin D include confusion, weakness, stomach pain, nausea, vomiting, and constipation, but in the long-term, the buildup of calcium in the blood can progress to bone pain and kidney issues.
So, while some people benefit from vitamin D supplements, it’s best to talk to your doctor first to make sure you’re not overdoing it.
2. Sunscreen Blocks Your Body’s Production of Vitamin D
Your body can make vitamin D from the sun thanks to ultraviolet B (UVB) rays, which are absorbed by the skin and then converted into an active form of the nutrient that your body can use to keep you healthy, explains Milton D. Moore, MD, a dermatologist, pharmacist, and founder of Moore Unique Skin Care, LLC.
Since sunscreen prevents sunburn by blocking UVB light, you might assume that sunscreen impairs your body’s ability to make or absorb vitamin D. But the truth is that sunscreen is technically just a filter for sun rays, says Anna Chacon, MD, a board-certified dermatologist at the Cleveland Clinic. In other words, “sunscreen cannot filter all of the rays completely,” she explains. That’s why it’s still possible to burn even after applying sunscreen.
Plus, adds Dr. Chacon, research shows that most people use much less sunscreen than they’re supposed to, meaning it’s highly unlikely that your sunscreen habits are affecting your vitamin D levels.
3. Healthy Vitamin D Levels Can Only Be Achieved Through Lots of Sun Exposure
Yes, the sun is an excellent source of vitamin D, but the unavoidable truth is that spending time in the sunshine comes with an increased risk of damage to not only your skin, but also your eyes and even your immune system.
If you’re wondering how much sunlight your body needs to absorb vitamin D, the Skin Cancer Foundation says that approximately 10 to 15 minutes of exposure to your arms, legs, abdomen, and back, two to three times a week, is sufficient for most people. But, again, considering the risk of life-threatening cancers such as melanoma, it’s a good idea to limit your sun exposure as much as possible.
Fortunately, spending time in the sun is far from your only means of getting enough vitamin D. Common food sources of vitamin D include salmon, tuna, tilapia, milk, yogurt, cheese, and mushrooms. (Reminder: If you have diabetes, consider checking your blood sugar before and after trying a new food to better understand how it affects your health, and reach out to your One Drop coach if you have questions.)
4. People with Melanin-Rich Skin Don’t Need to Worry About Sunscreen
Having more melanin in your skin may technically offer some natural protection from the sun’s UV rays, but everyone, of any skin color, is still at risk of developing sun-related skin cancers, explains Dr. Nazarian.
In fact, research shows that, even though melanoma is considered relatively rare among Black people, it’s usually associated with a worse prognosis than in white people, in large part because the former are more likely to be at an advanced stage of their cancer by the time they’re diagnosed.
What about melanin and vitamin D? Interestingly enough, melanin affects the body’s ability to absorb UVB rays from the sun, meaning people with dark skin usually require more UVB exposure than light-skinned people to produce the same amount of vitamin D, according to Harvard Health.
To be clear, though, that doesn’t mean people with dark skin should increase their sun exposure to get enough vitamin D. Again, it’s best to get your vitamin D from a variety of sources, including the sun, your diet, and, in some cases, supplements.
Need help finding healthy sources of vitamin D? Reach out to your One Drop coach for personalized recommendations and guidance.
This article has been clinically reviewed by Jamillah Hoy-Rosas, MPH, RDN, CDCES, and VP of clinical operations at One Drop.