Vitamin D is produced when your bare skin is exposed to sunlight. Using sunscreen blocks short wave ultraviolet B (UVB) rays from reaching your skin, causing vitamin D deficiencies in almost 1 billion people worldwide, according to a study published in May 2017 in The Journal of the American Osteopathic Association.
Kim Pfotenhauer, D.O., one of the researchers of the study, explains, “People are spending less time outside and when they do go out, they’re typically wearing sunscreen, which essentially nullifies the body’s ability to produce vitamin D.”
This brings up a dilemma. While it is important to protect your skin from the sun’s rays, which greatly increase your risk of skin cancer, vitamin D deficiencies can cause health problems such as loss of bone density and might contribute to diabetes, high blood pressure, cancer, and some autoimmune disorders, according to the U.S. National Library of Medicine. Vitamin D is also essential for your body to absorb calcium and phosphorous.
So how can you make sure you are both protecting your skin from skin cancer and premature aging while getting enough vitamin D?
According to the U.S. National Library of Medicine, most people need 600 international units (IU) of vitamin D per day; the exceptions are children under 12 months old, who need about 400 IU, and those over 70 years old, who need 800 IU. People with certain health conditions, such as diabetes or kidney disease, might be at higher risk of vitamin D deficiency and require higher daily intakes.
You can get vitamin D through sun exposure, foods, and supplements.
Sun exposure – Dr. Photenhauer indicates “there are healthy, moderate levels of unprotected sun exposure that can be very helpful in boosting vitamin D.” Because different skin types absorb the sun’s rays at different rates, for example, people with light skin absorb the sun’s rays very quickly, while dark skinned individuals absorb the UV rays much more slowly, there isn’t a specific amount of time that is universal. The length of time is also dependent on where you live. However, the American Osteopathic Association indicates that five minutes in direct sun, without using sunscreen, twice a week could be helpful.
Food – There are a number of foods that are fortified with vitamin D, including milk, yogurt, orange juice, and breakfast cereals. Some fish are good sources of vitamin D, including cod liver oil, swordfish, salmon, tuna, and sardines. Many people do not receive enough vitamin D from food alone. The National Institutes of Health (NIH) indicates that the average intake of vitamin D from food range from 144 IU to 288 IU per day.
Supplements – Vitamin D supplements are available for both vitamin D2 and D3. Both, according to the NIH, are equally effective in treating vitamin D deficiencies. As with all supplements, you should speak to your doctor about what type of supplement, and the strength, is best for you.
If you believe you have a vitamin D deficiency, it is recommended you talk with your physician before deciding on a course of action. High levels of vitamin D can be toxic and cause weight loss, heart arrhythmias, and lead to damage to the heart, blood vessels, and kidneys, according to the NIH.