Does Sunscreen Block Vitamin D From the Sun?
Most people know that calcium is essential for building and maintaining strong, healthy bones. However, this vital nutrient can only reach its full bone-strengthening potential in the presence of a sufficient amount of vitamin D, which helps the body to effectively absorb and use calcium. As a result, even if an individual is getting enough calcium, a vitamin D deficiency can cause that valuable calcium to go to waste, potentially leading to brittle bones and medical conditions like osteoporosis.
Because very few food sources are naturally rich in vitamin D, it is mostly derived from exposure to ultraviolet light; specifically, the ultraviolet (UV) B rays generated by the sun. In response to UVB exposure, the body forms vitamin D precursors on the skin, which are converted by the kidneys into the active form of vitamin D and then carried via the bloodstream to reach the bones throughout the body.
Most individuals need sun exposure to produce enough vitamin D for good health. However, UVB also causes sunburn and skin damage. In fact, it is a confirmed carcinogen and proven causal factor in most skin cancer cases. Sunscreens provide effective protection against sunburn and skin cancer by filtering UVB rays – the same UVB rays that stimulate the body to produce vitamin D. This leaves many people wondering whether it is possible to balance the beneficial and harmful effects of UV exposure from the sun.
To help address this dilemma, here are some tips on how to safely increase the body’s level of vitamin D:
- Increase consumption of foods that are natural sources of vitamin D, such as egg yolks, cheese and fatty fish (salmon and tuna).
- Consume vitamin D-fortified foods and beverages, such as dairy products, orange juice and cereal.
- Take nutritional supplements that contain vitamin D as recommended by a physician.
Researchers learn more every day, but the extent to which sunscreen interferes with the body’s production of vitamin D remains unclear. For now, the bottom line is this: the regular use of sunscreen has been proven to lower the risk of skin cancer. Because there is no scientifically validated, safe threshold level of UV exposure that allows for maximum vitamin D production without increasing the risk of skin cancer, most experts continue to recommend the daily use of sunscreen for everyone, including those who spend most or all of their time indoors.