Since I was a child my mom and my grandma always told me don't go out without a sunscreen, wear hat, seek the shade and if you can, don't go in the sun between 10am-4pm.
Many years ago I thought if I put a sunscreen on me and I repeat it in every hour I am safe from the harmful UV light. I was so wrong.
After my esthetician school and many researching and learning, I realized that there are lots of harmful and not effective sunscreen. I had to admit if I don't use the proper sunscreen, I am not protected at all.
So first we have to get to know better UVA, UVB and UVC and their effect to the skin.
It penetrates the skin deeper than UVB and it plays a major part in skin aging and wrinkling (photoaging). UVA damages skin cells (called keratinocytes) in the basal layer of the epidermis, where most skin cancers occur. UVA is the dominant tanning ray.