Sign out
Enjoying the outdoors can be great for your health — from getting some much-needed vitamin D to relieving stress. But too much sun comes with risks, too — like sunburn, skin damage, and over time, skin cancer.
Sunscreen is a big part of protecting yourself, but it can be hard to separate fact from fiction. To help you filter out the myths, here are some basic sun protection tips, straight from a dermatologist.
4 common sunscreen questions
What SPF should you use?
Many people think that SPF, or sun protection factor, tells you how long the sunscreen will work. But that’s not true. SPF measures how much UV radiation a sunscreen can absorb before it stops working.1 Don’t worry, though — Sarah Adams, MD, FAAD, a dermatologist with Kaiser Permanente in Southern California, has a quick answer for picking the right SPF.
“For me, the magic number is 30,” says Adams. SPF 30 blocks 97% of the UVB rays that cause sunburn.2 Higher SPFs offer a little more protection, but nothing is 100%.
You should reapply sunscreen every 2 hours, and also after getting in the water — regardless of the SPF. Even for sunscreens that say they’re waterproof. “They’re not truly waterproof,” says Adams. “So, if you go in the water, you should reapply it.”
Do moisturizers with SPF work?
According to Adams, the SPF in a moisturizer can work just as well as SPF in sunscreen. But you may not be applying enough to get the coverage you need.
“It’s the same as with sunscreen,” Adams says. “If you just use a very small amount of sunscreen because you don’t like the way it feels or you think it’s greasy, then you’re not truly getting the SPF that’s on the bottle.”
Depending on your skin type, you may not want to keep applying moisturizer throughout the day, either. So it’s generally a good idea to have a separate sunscreen if you’ll be spending much time outside.
“If you’re only going to and from your car or sitting by the window, then the SPF in your moisturizer is definitely better than nothing,” says Adams. “But if you’re going to the beach and playing beach volleyball, then maybe you want more of a dedicated product.”
What’s the difference between chemical and mineral sunscreen?
Chemical sunscreen absorbs rays within your skin cells, like a filter. Mineral sunscreen blocks sun rays by sitting on top of your skin. These sunscreens contain minerals such as zinc oxide or titanium dioxide. A simple way to identify a chemical versus mineral sunscreen is by texture and appearance. Chemical sunscreens are usually transparent and less thick than mineral options. “Both protect you from sun damage,” says Adams, “and there’s no clear evidence that one is better for your health or more effective than the other.”
However, some sunscreen chemicals can harm the environment, particularly coral reefs. If you’re planning a beach vacation, think about using a more eco-friendly mineral sunscreen. In fact, some places — like Hawaii — have outlawed chemical sunscreens to protect ocean life. Be sure to research your destination if you’re traveling, so you can pack accordingly.
For her own personal use, Adams likes a blend of minerals and chemicals. “I like that I’m getting some mineral protection but because it has a chemical mixed in, it’s a little bit thinner and lighter. But it absolutely has to be broad-spectrum,” she says. That way, it protects against both UVA rays, which contribute to premature aging, and UVB rays, which cause burning — and can lead to cancer. Sunscreens that aren’t broad-spectrum most likely won’t offer protection against UVA rays.
When should you see a dermatologist about sun damage?
Small changes in your skin are normal over time, even if you apply sunscreen the right way. But it’s important to know when you should see a doctor. Adams says that new growths, bleeding, scabbing, and itching are all signs to see a dermatologist.
You should consider more regular skin checks if you have:
- A high number of moles (100 or more, advises Adams)
- Personal or family history of skin cancer
- Fair skin
- Blue eyes
- Red hair
However, it’s important for everyone — no matter their skin tone — to stay protected from the sun. Using sunscreen helps prevent sun damage and lower the risk of getting skin cancer.
3 common sunscreen mistakes
It’s easy to make mistakes when using sunscreen. Here are some of the ones Adams sees most, and how to fix them.
Not applying it right
You should apply sunscreen evenly and thoroughly — more than you might think. Be extra aware of this when you’re using a spray sunscreen, says Adams. “Don’t step into the spray like you’re spraying perfume,” she explains. “You’re not going to get the density of sunscreen that you need to prevent burning that way — and you’re not putting it on evenly.” Instead, spray the sunscreen directly onto your skin and then use your hands to rub it in. This makes sure you cover your skin evenly.
Missing important spots
You may remember to apply sunscreen to your arms, legs, and face, but you could be missing some areas. “Your ears, neck, hands, and scalp are easy to burn,” says Adams, “and the top of your head is a common place for skin cancer to develop.” Long story short, sometimes you’re getting exposed to sun without even realizing it.
Using old or expired products
Whether you’re buying a new bottle or grabbing an old one at home, always check the expiration date. Direct sunlight can deactivate sunscreen too, so make sure to store yours in a cool place between uses so it lasts longer.
At the end of the day, find a product that’s a good balance of what’s effective and what you’ll use most often. “I always tell people,” Adams says, “the sunscreen that works is the sunscreen that you are actually going to put on your skin.”
Good health starts with prevention
From managing stress to quitting smoking, creating healthier habits can help prevent cancer. Discover more about prevention and cancer care with Kaiser Permanente.