Why does the sun sometimes burn our skin?

Some sunlight is essential for the formation of our bones as children, and to help us stay healthy and resist infection. However, if we stay in the Sun too long, some of its rays can cause the skin to go red and burn. It is better to avoid being in the Sun at mid-day, which is when the Sun’s rays are strongest. If you do spend time in the sun you should wear a hat, and keep your skin covered. It is also advisable to put some protective cream on your skin. People who stay in the Sun too long without protection not only get burnt, they may also suffer from sunstroke. This makes them feel sick and is very unpleasant.

People who are born in very hot countries often have darker colored skin. This is because, thousands of years ago, their ancestors developed extra melanin, the pigment which colors the skin and gives extra protection from the harmful ultraviolet rays of the Sun. Many races in Africa, India and the Middle East wear long, loose, clothes. This not only protects them from the light, but causes movement of air under the cloth which cools the body.