The sun gives out ultraviolet (UV) radiation which can be harmful to your body. UV radiation can cause skin cancer, premature aging of your skin and eye problems such as cataracts. It can also affect your immune system. You can prevent damage from the sun by covering your skin, using sunscreen, wearing sunglasses and a hat and by seeking shade. Exposing your bare skin to the sun for short periods of time can be beneficial because your skin uses UV to produce vitamin D. By checking your skin regularly you can spot the early signs of skin cancer. If you notice any changes to your skin or moles, you should see your GP.