Dr. Hirsch says there is still a misconception that there is little difference between SPF 30 and SPF 50, but: teeth “It’s a meaningful difference.” Specifically, when you wear SPF 30, 1.5 times as much UV rays get through the filter. So she minimum Apply SPF 50 to both your face and body when going outside.
In addition to looking for a high SPF rating, make sure your sunscreen is labeled “broad spectrum,” which means it protects against both UVB and UVA rays.
When should I use sunscreen?
It may sound silly, but you should wear sunscreen whenever you’re not in bed at night.
“No matter the season, the sun is always emitting harmful UV rays,” says the board-certified dermatologist. Mary LupoMD. “While you may not get a sunburn during the colder months, these UV rays can cause premature aging and DNA damage, so it’s important to protect your skin year-round.”
The DNA damage that leads to skin cancer is specifically caused by UVB rays. “UVB rays are at their highest intensity between 10 am and 4 pm,” says a board-certified dermatologist. Carolyn StullMD. UVA rays, on the other hand, “are present all day and penetrate deeper into the skin, damaging collagen and elastin and causing photodamage.”
If you spend most of your day indoors and near a window, that window may block UVB rays but not UVA. Azadeh ShiraziDr. MD recommends getting into the habit of wearing sunscreen indoors: “After all, we go outside to check the mail, walk the dog, or sit by a window. Over time, UV rays build up and have a negative impact on the health and appearance of our skin.”
And remember that you’re not only protecting yourself from UVA rays damaging your skin when you’re indoors: “While the majority of blue light exposure comes from the sun, digital devices emit high-energy visible light that some sunscreens may help protect against,” says Dr. Girshick.
How often should I reapply sunscreen?
In one word: VERY. “Reapply at least every two hours, or more often if you sweat or are in water,” says the board-certified dermatologist. Roberta Del CampoA medical doctor speaks charmThis is consistent with the reapplication frequency recommended by every expert we spoke to, even for sunscreens that claim to be water-resistant.
