Can sunscreen be reason of Vitamin D deficiency?

In the past several years, there has been much public debate about the importance of sunlight exposure for maintaining adequate levels of vitamin D, versus the importance of daily protection against solar ultraviolet (UV) radiation. Vitamin D is known to play an important role in bone health and maintaining muscle control.

Further studies have suggested that it plays a role in lowering blood pressure and reducing the risk of developing cancer, multiple sclerosis and arthritis. Vitamin D is provided in the diet, often at inadequate levels. The other major source of vitamin D is by the skin, following exposure to sunlight.

However, it is well documented that even small amounts of solar UV can produce acute and chronic skin damage, including skin cancer. As a result of these benefits and risks, people have heard confusing advice to forego use of sunscreens and even intentionally sunbathe to avoid a vitamin D deficiency.

What is the best sun strategy for the skin?

An important study is helping to set the record straight about sunscreen use and vitamin D. At the 2005 American Academy of Dermatology (ADD) annual meeting, P&G scientists in collaboration with Dr. Darrell Rigel, Clinical Professor of Dermatology at NYU, reported the impact of “safe sun strategy” on levels of vitamin D in humans. This study determined the average daily “dose” of solar UV in 92 female subjects from 5 geographically distinct cities throughout the U.S. The dose of UV was used to calculate the production of vitamin D in the presence and absence of SPF 15 sunscreen.

“We can estimate how much vitamin D is produced in the skin by a given dose of solar UV. Further, we know that SPF 15 sunscreen reduces the dose of erythemically weighted solar UV by 93%. Therefore, we can calculate the impact of daily use of SPF 15 sunscreen on the levels of vitamin D,” said J Nash, Ph.D., a P&G Beauty scientist and study author.

Using the most conservative assumptions, the estimated synthesis of vitamin D was equivalent to half the adequate intake even if SPF 15 sunscreen was applied properly. This production of vitamin D, together with current estimates of dietary intake, suggests that use of sunscreens would not produce a deficiency. These results do not refute the benefits of a “safe sun strategy,” including the use of SPF 15 sunscreen. Dr. Rigel recommends that people concerned with maintaining vitamin D levels should take a multivitamin, drink vitamin D-fortified milk or eat food rich in vitamin D, such as salmon. Daily use of SPF 15 sunscreen is strongly recommended by the AAD to diminish the long-term health effects of solar UV.