Answer: Sun exposure. Long term sun exposure and damage from the sun’s ultraviolet light leads to photoaging, which causes most wrinkles and undesirable skin changes. Of course, staying out of the sun and wearing UV-protective clothing are the best ways to prevent wrinkles, but not many of us will really do that. So, using a broad-spectrum sunscreen (offering UVA and UVB protection with an SPF of 30 or higher) every day is the most effective realistic way — to protect skin and look younger