Nightly News | June 04, 2013
>>> slowing down the signs of aging, something americans spend billions of dollars every year trying to do with a wide range of products but it turns out doctors now say the best anti-aging products appear to be sunscreen, and so this story is getting a lot of attention. we get our report tonight from our chief medical editor dr. nancy snyderman .
>> reporter: it used to be summertime and days in the sun and the quest for a deep, dark tan . most of us grew up believing suntanning was tops when it came to looking and feeling healthy. since then, scientists have learned a lot about the damaging effects of too much sun. in a new study researchers followed the progress of 900 white mostly fair skinned adults under age 55 living in australia. they assigned half to apply broad spectrum spf sunscreen daily or several times a day. the others free to use sun screen as they pleased.
>> after four and a half years those who applied sunscreen regularly had no detectible aging.
>> reporter: this study is one of the first measuring sun damaged skins in humans, not mice. the researchers measured participants' skin damage by making silicone casts of their hands at the beginning and end of the study. the casts revealed many more wrinkles among those not using sunscreen regularly.
>> this is a study which has for the first time shown evidence that sunscreen can prevent aging of the skin.
>> reporter: but it's not just the spf or sun protection factor that's so important when using a sunscreen. it's what type of rays it protects against.
>> when we're choosing the sunscreen, we're really looking for a broad spectrum that's uva and uvb protective sunscreen.
>> reporter: uva rays penetrate the skin more deeply while uvb rays damage the skin's outer layer but exposure to both types of the sun or tanning booths also increases the risk of developing skin cancer . the amount of sunscreen you should use every day is probably more than you would think. think of a golf ball applied everywhere that you have exposure and if you workout, run or swim, apply it liberally repeatedly throughout the day. even though this was done in caucasian people , people of all colors can get skin cancer so everybody regardless of color should use sunscreen.