The sun’s rays can be beneficial to human health, contributing to important biological processes such as the production and assimilation of Vitamin D, essential for strong bones and teeth. Excessive exposure can however harm the skin, leading to sunburn, photoaging, hyperpigmentation and even skin cancer.
There are three types of solar radiation: UVA, UVB and UVC. UVC is blocked by the ozone layer and thus never reaches the earth’s surface, but both UVA and UVB do. UVB is strongest during the summer months and in areas closer to the equator. It affects the most superficial layer of the skin (epidermis) where it can cause short term effects such as sunburn, and longer-term ones such as immunosupression and DNA damage. UVA on the other hand is present all year long and at all latitudes. It penetrates deeper into the skin, reaching the dermis, and is responsible for photoaging, hyperpigmentation, immunosuppression and DNA damage.
The skin has natural mechanisms to protect itself against UV radiation (tanning, anti-oxidant systems, immune repair) but these are often insufficient so it is important to adopt additional protective measures such as sun avoidance at peak hours, protective clothing and topical sun screen. The choice of sun screen depends on skin type and exposure conditions, although the general rule is the higher the protection, the better!.
Topical sun protection however is never able to completely block all UV radiation: the products are not always properly used. We sometimes forget to cover all areas of our body or don’t use enough quantity. Maybe we don’t use a sufficient sun protection factor or forget to apply it frequently. For this reason, oral sun protection is an excellent complement to topical protection, ensuring more complete prevention of skin damage and aging.