How to Choose the Best SPF Sunscreen

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If you have ever been to the sunscreen aisle at your local drugstore, you know how overwhelming it can be. The bottles and tubes are all full of abbreviations, such as SPF, UVA, and UVB. And further options such as waterproof and water-resistant only add to the confusion. Also, don't forget the wide array of brands you have to choose from. You're not alone. According to a study published in JAMA Dermotology, fewer than half of the patients at a dermatology clinic knew the meaning of terms like “broad spectrum” and “SPF.”

But, if you get overwhelmed and neglect to take proper precautions to protect your skin, you'll probably find yourself with a severe sunburn (or worse) and unable to enjoy your time in the sunshine. So, let's take a closer look at the world of sun safety, so you can be well prepared.

Sun Protection Factor

SPF stands for sun protection factor. It tells you how long you can stay in the sun without getting burned while wearing that sunscreen versus how long you'd be able to stay in the sun before getting burned without wearing that sunscreen. In other words, say it takes you 15 minutes to burn without wearing sunscreen. Applying an SPF 10 means it will take you 10 times longer to burn, or 2.5 hours.

The American Academy of Dermatology recommends wearing an SPF 30 or higher for maximum protection. But, you may be thinking to yourself, ​there are sunscreens with SPF 70—is it necessary to go that high?

A high SPF doesn't mean better protection. An SPF 50 only provides 1% to 2% more protection than an SPF 30.

A sunscreen with a high SPF is capable of protecting your skin for a longer amount of time, but think about the typical conditions during which we wear sunscreen: we're swimming, sweating, and toweling off. No sunscreen, whether SPF 15 or 60, can withstand that. Any sunscreen, regardless of SPF, must be reapplied often, especially after swimming, sweating, and drying off.

UV Index

The UV (ultraviolet) index is a daily prediction of the intensity of UV radiation at noon when the sun's rays are at their most intense. UV index is measured on a scale of one to 11+, with one signifying the lowest risk of UV exposure and 11+ signifying the highest risk of UV exposure.

There are several factors that determine the UV index, including season, latitude, and altitude. The UV index is highest during spring and summer. UV radiation is highest at the equator, so the closer you are to it, the more intense the radiation. Air also becomes thinner at high elevations, which causes UV radiation to intensify with altitude.

UVA vs. UVB Protection

UVA rays are mostly responsible for the aging effects of the sun on the skin while UVB rays are responsible for sunburns and skin cancer. However, it's important to note that overexposure to UVA rays can also lead to skin cancer.

The label on sunscreen will indicate whether it provides UVA or UVB protection. In order to prevent skin cancer and early skin aging, the sunscreen needs to protect against both UVA and UVB rays, with a minimum SPF of 15. Otherwise, the sunscreen is only preventing sunburn and not skin cancer.

Also, note that SPF only measures UVB protection, so choose a product that states "UVA/UVB" protection or has "broad-spectrum" protectant.

Waterproof vs. Water-Resistant

The level of SPF is compromised when your skin comes into contact with water. This means that you must reapply sunscreen as soon as you are out of the water or if you are participating in an activity where you are sweating.

If you are looking for a sunscreen to use while in the water, choose a sunscreen that is "waterproof" or "water-resistant." Waterproof sunscreens are not actually completely waterproof but provide protection in the water for 80 minutes. Water-resistant sunscreens provide only 40 minutes of protection.

Sun Safety Tips

Since SPF claims are strictly regulated by the FDA, SPF labeling is consistent from company to company, so switching between brands is not a problem.

The right sunscreen for you is the one you're most likely to wear. So be sure to find the one that you like the feel, scent, and texture of while matching the SPF level required by your individual skin tone. Also, remember to keep these sun safety tips in mind:

  • Thoroughly apply sunscreen to your entire body, every two hours when outdoors, even on cloudy days, and after swimming or sweating. Sunscreen should even be applied on parts covered with clothing.
  • If using spray sunscreen, be sure to spray it into your hands and rub it in to ensure even coverage.
  • Invest in ultraviolet protection factor, or UPF, clothing, if possible. This will provide UVA and UVB broad-spectrum sun protection built straight into your clothing's fabric. The highest-rated UPF certification is UPF 50+, which blocks out more than 98% of the sun's ultraviolet rays.
  • Wear a wide-brimmed hat.
  • Cover exposed skin. 
  • Stay in the shade as much as possible.
  • Remember that UV index is much higher closer to the equator and when surrounded by water that reflects sunlight. In this case, waterproof sunscreen with SPF 30 and broad-spectrum protection is your best bet.
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Article Sources

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  1. Kong BY, Sheu SL, Kundu RV. Assessment of consumer knowledge of new sunscreen labels. JAMA Dermatol. 2015;151(9):1028-30. doi:10.1001/jamadermatol.2015.1253

  2. The American Academy of Dermatology. Sunscreen FAQs.

  3. World Health Organization. Ultraviolet radiation and health.

  4. American Cancer Society. Ultraviolet (UV) radiation. Updated July 10, 2019.

  5. American Academy of Dermatology. How to decode sunscreen labels.

  6. Skin Cancer Foundation. Sun-protective clothing. June 2019.