The effect of high SPF sunscreen application on vitamin D

防晒霜可以防止晒伤和皮肤癌，目前的指导方针是，当预测最大紫外线指数至少达到3时，应该常规使用防晒霜。然而，在实验室实验中涂抹防晒霜会减少维生素D的产生，而且人们担心经常涂抹高SPF防晒霜可能会增加维生素D缺乏的风险。我们建议进行一项随机对照试验，以确定坚持目前的指南是否会降低维生素D。

Sunscreen prevents sunburn and skin cancer, and current guidelines are that it should be routinely used when the maximum UV index is forecast to reach at least 3. However, applying sunscreen in laboratory experiments reduces vitamin D production, and there is concern that regular application of high SPF sunscreens might increase the risk of vitamin D deficiency. We propose a randomised controlled trial to determine if adhering to the current guidelines decreases vitamin D.