Suncare Week

The 10 Commandments Of Sunscreen Use

Follow these every. single. day.

Dermatologists on the 10 daily sunscreen rules to follow for your healthiest skin.
Getty Images/Moyo Studio

Sunscreen is going through a major glow-up. From sunscreen-serum hybrids to SPF that doubles as makeup, these new formulas actually make you *want* to reapply. In Bustle’s Suncare Week, we’re doing a deep dive on the latest innovations in sun-care, from textures to technology.

Sunscreen is its own complex category within the skin care umbrella. Though everyone knows it’s an essential part of your daily beauty routine, there’s much, much more to it than that. It’s an FDA-regulated product — so it’s treated like an over-the-counter drug — because it’s quite literally your antidote to serious skin (and even health) damage. To make sure you’re getting the most protection possible, your daily sunscreen use should follow certain protocols.

Besides wearing it 365 days a year, it’s also key to use the right sun protection product, apply it in all the right places, and adjust your sun exposure based on when you slather on your SPF. Of course, one shouldn’t rely solely on sunscreen: “While sunscreen is one of the essential ways to protect your skin from the sun, it’s also important to seek shade, avoid peak hours in the sun between 10 a.m. and 2 p.m., and wear sun-protective clothing and wide-brimmed hats,” says Dr. Marisa Garshick, M.D., a board-certified dermatologist with MDCS Dermatology.

For the non-negotiable daily sunscreen rules, Bustle spoke with top dermatologists for their intel — here, pros share the 10 commandments of SPF use.

We only include products that have been independently selected by Bustle's editorial team. However, we may receive a portion of sales if you purchase a product through a link in this article.

1. Broad-Spectrum Sunscreen Is Your Best Bet

Whichever sunscreen you go with, make sure it’s got broad-spectrum coverage — or else you won’t be fully protected from the sun’s harmful rays. “It’s important to find a product labeled ‘broad-spectrum,’ which indicates coverage against UVA and UVB,” says Garshick. “UVA damage can contribute to signs of aging as well as skin cancer,” she explains, while UVB rays are what can lead to reddening or a dreaded sunburn (and can also contribute to skin cancer).

Read product labels carefully to keep your complexion in check — your SPF bottle will call out if it’s broad-spectrum.

2. How Much Sunscreen You Use Matters

Yes, you get one gold star if you apply your SPF every day — but you’ll only be fully protected if you use the right amount of product. “In order to get the protection labeled on the bottle, it’s important to apply enough sunscreen,” says Garshick. For your face, she recommends a nickel-sized amount “or two finger-lengths,” while a full shot glass is sufficient for your body. Or you can follow a simpler philosophy: “Whatever amount you think you need, apply more,” says Dr. Dhaval Bhanusali, M.D., a board-certified dermatologist and founder of Hudson Dermatology and Laser Surgery in New York City.

3. Your Sun Protection Factor Should Be At Least 30

Common sense would make you think an SPF 100 is a lot stronger than an SPF 30 — but that’s not how it works. “Don’t fall for a super-high SPF number,” says Dr. Corey L. Hartman, M.D., dermatologist and founder of Skin Wellness Dermatology in Birmingham, Alabama. “Generally, SPF 30 filters about 97% of UV light and SPF 50 filters about 98%. SPF higher than 50 doesn’t confer any significant additional protection.” For reference, Garshick says an SPF 15 blocks 93% — so always go with an SPF of at least 30.

4. Wear Sunscreen Indoors

Even though you may associate sunscreen with the outdoors, your beach bag, or poolside vacations, it’s just as important to wear when you’re inside, too. “You should wear SPF even when you WFH,” says Dr. Rita Linkner, M.D., a board-certified dermatologist and founder of RVL Skincare. “Infrared heat and visible light come off of screens and light bulbs, so use a sunscreen daily to combat the pigmentation risks associated with this type of light energy.” The latter source is what you might know as blue light, which comes from everything from your iPhone to your TV and causes skin inflammation and premature aging as well as dark spots.

Not only that, but sometimes the sun’s rays sneak indoors. Harmful UVA rays can hit your skin through windows, adds board-certified dermatologist Dr. Elizabeth Mullans, M.D., so whether you’re driving in a car or sitting at your sunny desk, SPF application (and reapplication) rules still apply.

5. Also Wear SPF When It’s Cloudy Outside

It’s still a common misconception that you only need SPF when the sun’s out. This is false: Besides wearing sunscreen inside, you should also be applying your bottle of SPF when it’s cloudy. “Often, people think if they don’t feel the sun, they’re not getting exposed to UV rays,” says Dr. Azadeh Shirazi, M.D., a board-certified cosmetic dermatologist, who explains that cloudy days put you at risk for sunburn. “While clouds do reduce some of the sun’s UV rays, they don’t block all of them.” BTW: Rainy and cold days count, too, adds Garshick.

6. Allow Your SPF To Have Enough Dry Time

It’s unfortunate, but not every kind of sunscreen fully works the second you put it on. “Allow enough time for sunscreen to dry and become effective,” says Hartman. This is the case if you’re using a chemical-based SPF versus a mineral sunscreen: The former requires more time than the latter since it needs to be soaked into your skin (mineral ones, which contain titanium dioxide and/or zinc oxide, are physical barriers that block UV rays). Either way, Bhanusali suggests applying SPF (chemical or mineral) about 30 minutes ahead of sun exposure to be extra safe.

7. Apply SPF To The Oft-Forgotten Areas

Your face, chest, and appendages tend to steal the sunscreen application spotlight — but don’t “neglect the little guys,” says Dr. Ava Shamban, M.D., a board-certified dermatologist based in Los Angeles and founder of Ava MD Dermatology, SkinFive Medical Spas and The Box by Dr. Ava. As in: your scalp, ears, lips, and eyes, among others.

“These are the areas we don’t often think about when applying SPF, but they’re also high-risk areas for skin cancers,” says Shirazi. “The scalp is exposed to direct, unshielded UV rays, and the ears, eyes, and lips are delicate and at greater risk of damage.” Keep a lip balm with SPF on hand, apply your sunscreen to your eyelids, the tops of your feet and ears, and between your fingers and toes, says Shamban. And consider a sunscreen mist or powder to keep your scalp protected.

8. Sunscreen Does Expire, So Make Sure Yours Hasn’t

You might be getting away with using that blush you bought years ago or a mascara tube that’s due for a replacement, but it’s definitely a bad idea to use SPF that’s too old. “Any sunscreen that is past its expiration date has lost its efficacy and can potentially cause an atopic reaction,” says Shamban. That’s due to factors like time since manufacturing and oxidation (exposure to oxygen). But, since it’s FDA regulated, every sunscreen has to signify this date on its packaging — so check it before heading to the beach. Shamban’s tip? “When in doubt, toss it out,” she tells Bustle. And, to ensure your fave SPF stays fresh for as long as possible, store it indoors — heat can damage it and diminish its protective powers, she explains.

9. Pair Your Sunscreen With Antioxidants

Fun fact: Your trusty vitamin C serum can come in handy for your sun protection game. Studies show that antioxidants — applied topically — can boost how effective your sunscreen is. “Adding an antioxidant-rich product prior to sunscreen application can help protect your skin against free radicals and oxidative stress,” says Shamban. Think of your antioxidant skin care and your SPF as synergistic BFFs. (Just note that an antioxidant serum alone won’t protect you from sunburn or UVA/UVB rays.)

10. Know How Often To Reapply Sunscreen

Peek at the directions on any sunscreen bottle and you’ll come across the word “reapply.” This one’s a biggie: That dollop of SPF you applied in the a.m. won’t protect you at the beach four hours later. “The benefits of sunscreen wear off, so it’s important to reapply to maintain full protection,” says Garshick. Dermatologists recommend reapplying at least every two hours, but there are special instances to keep in mind.

If you’re sweating a lot, in more intense sunlight, or spending an extended period of time outside, Shamban recommends doubling down on sunscreen: Reapply every 60 to 90 minutes with at least SPF 30, and “add a hat or sun-protective clothing,” she tells Bustle. Then, every two to two-and-a-half hours is ideal for refreshing your sunscreen indoors, she says. And, while some SPF products are water-resistant, Garshick says to reapply sooner than two hours if you’re getting wet to maintain the full benefits. Whatever the scenario, Bhanusali suggests setting a timer on your phone so you never forget and your complexion stays nice and healthy.

Studies referenced:

Amaro-Ortiz, A. (2014). Ultraviolet Radiation, Aging and the Skin: Prevention of Damage by Topical cAMP Manipulation. Molecules.

Andersen, P. (2010). Environmental Cues to Ultraviolet Radiation and Personal Sun Protection In Outdoor Winter Recreation. Arch Dermatol.

Darr, D. (1996). Effectiveness Of Antioxidants (Vitamin C And E) With And Without Sunscreens As Topical Photoprotectants. Acta Dermato-Venereologica.

Diffey, B.L. (2001). When should sunscreen be reapplied?. J Am Acad Dermatol.

Mahmoud, B. (2008). Effects of visible light on the skin. Photochem Photobiol.


Dr. Marisa Garshick, M.D., a board-certified dermatologist with MDCS Dermatology

Dr. Dhaval Bhanusali, M.D., a board-certified dermatologist and founder of Hudson Dermatology and Laser Surgery in New York City

Dr. Corey L. Hartman, M.D., dermatologist and founder of Skin Wellness Dermatology in Birmingham, Alabama

Dr. Rita Linkner, M.D., a board-certified dermatologist and founder of RVL Skincare, PC

Dr. Elizabeth Mullans, M.D., board-certified dermatologist based in Houston, Texas

Dr. Azadeh Shirazi, M.D., a board-certified cosmetic dermatologist

Dr. Ava Shamban, M.D., a board-certified dermatologist based in Los Angeles and founder of Ava MD Dermatology, SkinFive Medical Spas and The Box by Dr. Ava.