A new study in the British Journal of Dermatology suggests that optimal use of sunscreen will prevent sunburn while not compromising synthesis of vitamin D in the human body.
Sunlight contains UVA and UVB rays. UVB is needed for the production of vitamin D, a nutrient essential for calcium absorption and bone growth promotion. UVB is also responsible for sunburns and skin cancers. Sunscreen can mitigate the adverse effects of UVA and UVB radiation, but the concern is that it might also hinder the body’s synthesis of vitamin D.
The investigators found an increase in vitamin D levels during a week of sunny, high UV index weather when sunscreen was used properly. Comparisons were made between two sunscreen formulations: one with a low UVA protection factor (UVA‐PF) and one with a high UVA-PF. They concluded that “A high UVA‐PF sunscreen enables significantly higher vitamin D synthesis than a low UVA‐PF sunscreen because the former, by default, transmits more UVB than the latter.” The study indicates that proper use of sunscreen will prevent sunburns and not compromise vitamin D levels.
Sunnier months are on the horizon, so it is important to stress the significance of sunscreen use; the National Cancer Institute indicates that the number of new cases of melanoma have increased steadily in the last few decades.