Except for humans, all primates live in tropical or sub-tropical areas where the sun is very bright. In the U.S. the only sub-tropical area is Hawaii. So people were meant to live in areas of brighter sunlight and to be out in the sunlight a lot.
It has hurt the health of people to be afraid of the sun and to wear sunscreen. They have found that vitamin D can also reduce type 1 diabetes and autism if the pregnant mother and new born baby get enough vitamin D. I just learned that the top paid model, Gisele Bundchen, does not wear sunscreen. That can help people to learn that sunlight is great for health.