We’ve all learned the importance of sun protection (including sunscreen) and covering up when we’ll be out in the sun to help prevent skin cancer. However, with so much emphasis on this protection, you may have forgotten that there are benefits to allowing your body to absorb a limited amount of sunshine without protection for a short amount of time each day.
This short amount of unprotected sun time stimulates your body to produce vitamin D. This fat-soluble vitamin is a powerful immune system regulator and helps the body absorb calcium and phosphorous, keeping bones and teeth strong. Those lacking adequate amounts of vitamin D risk bone abnormalities including osteoporosis. You can get enough vitamin D from either exposing bare skin to sunlight or by taking supplements. Unfortunately, you can’t get the right amount of vitamin D for optimal health from food alone.
Vitamin D has the following health benefits:
Some recent studies estimate that up to 50% of adults worldwide are deficient in vitamin D levels – especially in the winter because vitamin D has a half-life of only two weeks.
How long should I stay in the sun without sunscreen to stimulate vitamin D production?
It varies, according to the time of year, time of day, proximity to the equator, and your skin type. Typically, your body can make all the vitamin D it needs for the day in about half the time it would take for your skin to start getting pink, an indicator that it’s starting to burn. For fair-skinned people, that’s between five and 15 minutes, and again ― is about half the time it would take for your skin to start getting pink and burning. Monitor the time carefully and seek shade or apply sunscreen as soon as your skin starts getting pink! People with very dark skin may need to spend an hour or two in the sun to get enough vitamin D and/or they may need to take supplements. As we get older, it becomes more difficult for our bodies to produce vitamin D, so we need to take supplements.
How much vitamin D do you need each day?
Various organizations have different official recommendations. Your best bet is to ask your medical provider. The Vitamin D Council recommends that adults take 5,000 IUs (international units) per day, the Endocrine Society recommends adults take 1,500-2,000 IU/day and the Food and Nutrition Board, where the U.S. Government gets its official recommendations, advises 600 IU/day for adults and 800 IU/day for seniors. When choosing a vitamin D supplement, opt for vitamin D3 (rather than D2) because it’s easier for your body to utilize.
How much vitamin D does the body make when skin is exposed to sunlight?
When bare skin is exposed to the sun, your body is capable of making large quantities of vitamin D from the sun’s ultraviolet B (UVB) rays. And remember: you don’t need to tan or burn to achieve this. Your body can make 10,000 to 25,000 IU in a rapid amount of time – before your skin begins to get pink! The more skin you expose – such as your back vs. only your arms – the more vitamin D you will make.
Many factors influence how much vitamin D you can make, including the time of year, time of day, distance from the equator, and your skin type. When the sun’s rays hit the Earth at an extreme angle, such as during midwinter and in the morning or evening during summer, there aren’t enough UVB rays reaching the Earth’s surface to stimulate vitamin D production. There’s an easy way to tell: if your shadow is longer than you are tall, there aren’t sufficient UVB rays reaching you to stimulate vitamin D production.
If you work inside most weekdays, the Vitamin D Council recommends taking a vitamin D3 supplement on days when you’re not outside in the sun to stimulate your body’s internal vitamin D factory. Your doctor can advise the right vitamin D supplementation strategy for you. You’ll most likely need to depend solely on supplements in the wintertime, and a mix of supplements and natural sunshine in the summer. You can read more on the Vitamin D Council’s website.
Please remember: after you’ve spent the short amount of time it takes for your body to start producing vitamin D naturally, go into the shade, cover up or apply sun protection to prevent skin from burning. With the sun’s intense summer rays, a little goes a long way!