What’s the most bulletproof way to prevent sun damage to your skin? Staying out of the sun. But avoiding the sun is a horrible way to spend your time, especially when the sun’s rays are partially responsible for lifting your mood.

So, what’s best thing we have to protect the surface of our skin and the many layers underneath? Sunscreen.

We talked to experts and did the research to clear up common sunscreen confusion. From SPF numbers to skin types, here’s every question you had about sunscreen, answered.

New York dermatologist Fayne Frey reminds us that “no sunscreen is 100 percent effective at preventing burning and skin damage.” She also notes that sunscreen “can increase the amount of time you can be outside.”

And the amount of time spent outside is somewhat correlated to SPF.

sunscreen

Recent research shows that SPF 100, when compared with SPF 50, makes a real difference in protecting your skin against damage and burns. At minimum, you’ll want SPF 30.

Frey also adds that higher SPFs tend to be stickier, so some people don’t like them as much. But that extra protection is worth it for a beach day, even if you don’t want to opt for it daily.

To recap: “SPF 30 is the minimum I recommend, but higher is always better,” says Frey. Thinkbaby SPF 30 Stick ($8.99) covers the basics without the gluelike feeling. Plus, the stick makes for easy reapplying on-the-go.

What is SPF?SPF, or sun protection factor, measures how much solar energy is required to cause a sunburn when you’re wearing sunscreen compared with unprotected skin. A sunscreen with an SPF of 30, when used as directed, prevents 97 percent of UVB rays from reaching your skin. SPF 50 blocks 98 percent. It’s important to remember that while higher SPFs offer more protection, they don’t last any longer than lower numbers, so you need to reapply them just as often.

The sun emits different types of light rays, two of which are primarily responsible for damaging your skin: ultraviolet A (UVA) and ultraviolet B (UVB). UVB rays are shorter and can’t penetrate glass, but they’re the ones that cause sunburns.

UVA rays, which can get through glass, are more insidious because they affect your skin beneath the surface even when you can’t feel it burning.

For that reason, you’ll want to make sure your sunscreen says “broad spectrum,” “UVA/UVB protection,” or “multi-spectrum” on the label. The term “broad spectrum” is the one you’ll most often see in the United States because it’s regulated by the U.S. Food and Drug Administration (FDA).

Is sunscreen from Europe or Japan better?Possibly. Sunscreens from other countries have a wider variety of sun-blocking ingredients. These sunscreens list a PA factor, a measure of UVA protection that ranges from “+” to “++++.” The PA rating system was developed in Japan and is only starting to catch on here in the United States.

Monique Chheda, a Washington, DC-area dermatologist, adds that “usually the two ingredients that provide UVA coverage are avobenzone and zinc oxide, so you definitely want to make sure your sunscreen has one of these.”

To recap: Both UVB and UVA rays cause skin cancer and signs of aging, so always opt for a broad-spectrum sunscreen with a minimum of SPF 30 or higher. Murad City Skin Age Defense SPF 50 ($65) sunscreen has a PA rating of ++++, indicating it has excellent protection against UVA rays.

You’ll hear the terms physical (or mineral) and chemical sunscreens. These terms refer to the active ingredients used.

Renaming physical vs. chemicalSince zinc oxide and titanium dioxide are technically chemicals, it’s actually more accurate to refer to physical sunscreen as “inorganic” and chemical as “organic.” There’s also only a 5 to 10 percent difference in the way these ingredients work, as both types absorb UV rays.

Physical (inorganic) sunscreen

There are only two inorganic sunscreen ingredients approved by the FDA: zinc oxide and titanium dioxide. It’s been thought that inorganic sunscreens create a protective barrier on the surface of your skin that reflects and scatters UV rays away from your body. However, recent research suggests that inorganic sunscreens actually protect skin by absorbing up to 95 percent of the rays.

Best physical sunscreens

Beauty facts! Physical sunscreens typically leave behind a white cast, unless you are using a tinted product or one that uses nanotechnology to break down particles. Also, while physical sunscreens are branded as “natural,” most aren’t and need to be processed with synthetic chemicals in order for sunscreen to glide smoothly onto your skin.

Chemical (organic) sunscreen

All the other active ingredients that aren’t zinc or titanium are considered chemical sunscreens ingredients. Chemical sunscreens absorb into your skin like lotion instead of forming a barrier on top of the skin. These active ingredients “cause a chemical reaction that converts the UV light into heat so that it can’t harm the skin,” explains Chheda.

Best chemical sunscreens

Chheda encourages her patients to use whichever kind they prefer but cautions that when opting for a purely physical sunscreen, you need to look for one with at least a 10 percent concentration of zinc oxide in order to get broad-spectrum coverage.

“I wear sunscreen 365 days a year,” Frey says. “I brush my teeth in the morning and I put on my sunscreen.”

Whether you’re spending the afternoon in the sun or not, make sure you’re applying enough sunscreen for it to actually be effective — most of us don’t. Frey and Chheda both say that the average person in a bathing suit needs a full ounce (or a full shot glass) to cover all exposed areas, including your face, every two hours. To make reapplying easier, try a spray sunscreen like Banana Boat Sun Comfort Spray SPF 50 ($7.52).

If you’re at the beach for the day with your family — say six hours out in the sun — each person needs at least a three-ounce bottle all to themselves. If you’re not in the water, throw on a shirt and hat and sit in the shade. Every bit of coverage makes a difference.

People with dark skin tones or those who tan easily shouldn’t skimp either.

“Your skin tone shouldn’t decide how much sunscreen you wear. Everyone, regardless of skin color, should apply an adequate amount of sunscreen to ensure full protection,” Chheda advises. Skin cancer survival rates are lower in nonwhite populations, which may be due to the belief that darker skin tones don’t need sunscreen.

Even if you’re not spending the afternoon at the pool, you’re still guaranteed to come into contact with UV rays through the window or by peeking outside. Studies show that daily use of sunscreen can significantly lower your risk for skin cancer and aging skin (defined by wrinkles, hyperpigmentation, and dark spots).

Reapplication reminders: Always reapply sunscreen. Aim for every two hours if you’re outside. What you initially put on can move or shift throughout the day. It also takes about 20 minutes for sunscreen to work. If your sunscreen has thicker zinc oxide, you may be able to get away with less sunscreen, but if you’re unsure, don’t risk it!

As far as sun protection goes, according to Frey, the only real difference between face and body sunscreen is the size bottle it’s sold in. You don’t need to buy a separate bottle of sunscreen for your face if you don’t want to. There are some great combo products labeled for face and body such as La Roche-Posay Anthelios SPF 60 ($35.99).

That said, your face is often more sensitive than the rest of your body, so many people prefer a lightweight, nongreasy sunscreen formulated specifically for the face, especially for everyday wear. These are less likely to clog pores, cause breakouts, or irritate skin. Neutrogena Sheer Zinc Dry Touch SPF 50 ($6.39) fits these criteria nicely.

You should also avoid using spray sunscreens on your face, since it isn’t safe to inhale them. If you’re in a pinch, spray the sunscreen on your hand first and rub it in.

Stick sunscreens, such as Neutrogena Ultra Sheer Stick Face and Body SPF 70 ($8.16), make a nice on-the-go alternative and are easy to apply to the delicate skin around your eyes.

For babies and kids, as well as those with sensitive skin, dermatologists recommend physical sunscreens since they’re much less likely to cause rashes or other allergic reactions. For little ones, a hypoallergenic sunscreen formulated with zinc oxide such as Thinkbaby SPF 50 ($7.97) is a great choice.

Since it can be hard for kids who are a bit older to sit still for sunscreen applications, spray sunscreens, such as Supergoop Antioxidant-Infused Sunscreen Mist SPF 30 ($19), can make the process less of a chase. Be sure to hold the nozzle close and spray until the skin glistens to be sure you’re applying enough.

All of the dermatologists we spoke to stressed that the active ingredients in sunscreen are vigorously tested for safety by the FDA. That said, they agree chemical absorbers are more likely to cause skin irritation, so if you have a skin condition like eczema or rosacea, or if you’re prone to allergic reactions, stick with sunscreens that use zinc oxide and titanium dioxide.

Fragrances are also irritating to many people, so a physical sunscreen that’s also fragrance-free and hypoallergenic is ideal.

If you have questions about sunscreen safety, Dustin J. Mullens, a dermatologist in Scottsdale, Arizona, recommends checking out the Environmental Working Group’s sunscreen guide, which gives safety ratings to hundreds of sunscreens based on scientific data and literature.

In May 2018, Hawaii banned chemical sunscreen ingredients oxybenzone and octinoxate, which scientists believe contribute to coral reef bleaching.

But Hawaii’s new law doesn’t go into effect until 2021, so for now the targeted ingredients are still circulating on store shelves.

Overall, it’s not a bad idea to be proactive and opt for reef-safe sunscreens that don’t include oxybenzone or octinoxate, such as Blue Lizard Sensitive SPF 30 ($26.99) which gets its UV protection from zinc oxide and titanium dioxide.

Not all mineral sunscreens are totally in the clear, though. Many mineral sunscreens contain microscopic-sized particles of zinc oxide and titanium dioxide which are called nanoparticles. Recent research, still in the early stages, suggests that these nanoparticles may also be harmful to coral reefs.

If you want err on the side of caution, go with a sunscreen that includes non-nano zinc oxide on the ingredients list, such as Raw Elements Face + Body SPF 30 ($13.99).

Sunscreen disruptionOxybenzone is one chemical sunscreen ingredient that’s been linked to hormone disruption. However, a 2017 paper notes that you’d have to use this ingredient continuously for 277 years for it to disrupt your hormones. Current studies also show that nanoparticles are safe for humans and don’t go deep into your skin (only onto the outer dead layer).

From Amazon to Ulta, you’ve got literally hundreds to choose from. You can start with the basics: Choose broad spectrum and an SPF of at least 30. From there, consider factors that’re important to you like whether you have a skin condition or whether you prefer the application of a stick over a cream.

If your skin is…

  • Dry. Look for a sunscreen that also contains a moisturizer and avoid sprays since they often contain skin-drying alcohol.
  • Darker. Any type of chemical sunscreen should work since they’re designed to rub in fully without leaving a white residue. If you prefer a physical sunscreen, look for one that’s marked ‘sheer.’
  • Acne-prone. Avoid creams since they tend to be greasy and heavy and can clog pores.
  • Oily. Oily skin isn’t necessarily acne-prone, but look for a lightweight, gel-based sunscreen that dries quickly on your skin. Sunscreens like this often contain alcohol.
  • Sensitive. Stick to physical sunscreens and make sure the product you buy is alcohol- and fragrance-free.

At the end of the day, “the best sunscreen is the one you’re going to use,” Frey says. And if you’re really looking to cover up, wear a hat, invest in sun-protective clothing, and stay in the shade or indoors — especially in the bright afternoon sun between noon and 4 p.m.


Rebecca Straus is a writer, editor, and plant expert. Her work has appeared on Rodale’s Organic Life, Sunset, Apartment Therapy, and Good Housekeeping.

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