Making Sense of Sunscreens

With about 3.5 million cases diagnosed each year in the U.S., skin cancer is the most common of all cancers, according to the American Cancer Society. A big risk factor is too much exposure to ultraviolet (UV) radiation from sunlight. That’s why dermatologists encourage the daily, liberal use of waterproof sunscreens, and lip balms that deliver broad-spectrum protection against both UVA and UVB rays.

There is a dizzying variety of spray, lotion, and stick sunscreen options available, but your first consideration should be what’s listed on the ingredient panel.

For starters, the higher the SPF number, the more sunburn-inducing UVB light will be filtered out—but not UVA. According to the Environmental Working Group, “A sunscreen lotion’s SPF rating has little to do with the product’s ability to shield the skin from UVA rays. As a result of the FDA’s restrictions on ingredients and concentrations, U.S. sunscreens offer far less protection against UVA than UVB, particularly those products with the highest SPF.”

SPF numbers can be misleading too. For example, an SPF 30 blocks roughly 93 percent of sunburn rays, whereas an SPF of 50 blocks about 98 percent.

Joyce Imahiyerobo-Ip, MD, director of cosmetic dermatology at South Shore Medical Center in Norwell, Mass., explains that there are two basic categories of sunscreens: physical blockers and chemical blockers. “Physical blockers contain two main ingredients, zinc and titanium oxide, which are natural minerals that block the UV rays of the sun,” she says. “Chemical blockers typically include a combination of two to six ingredients including oxybenzone, avobenzone, octocrylene, and octinoxate.” Physical blockers formulated with zinc and titanium oxide are best for outdoor activities. “I find these ingredients to be the broadest spectrum and most protective against the sun’s rays, and they are a cleaner alternative to chemical blockers,” she says.

When looking for a sunscreen with zinc and titanium, opt for one that has micronized particles instead of nanoparticles on the ingredient label. Natural zinc oxide leaves a chalky white residue on most skin types, so most sunscreens feature zinc in nano- or micronized particle sizes to eliminate the pasty lifeguard look. “Nanoparticles are so small, they can be absorbed into the skin (as opposed to larger particles which sit on top of the skin), where they may be potentially harmful,” Imahiyerobo-Ip says. “In order to get the benefits of zinc oxide without the risk of nanoparticles, I recommend that clients opt for micronized zinc oxide. These particles are smaller (preventing the white residue) but not so small that they are absorbed into the skin.”

Adam Scheiner, MD, a Tampa, Fla.-based cosmetic surgeon and author of The True Definition of Beauty, agrees, and also suggests avoiding certain other sunscreens. “Those that use [solely] oils such as raspberry seed oil, coconut oil, carrot seed oil, shea butter, and almond oil do not provide enough protection from the sun,” he warns. Scheiner’s favorite sunscreens contain both zinc oxide and titanium dioxide because they reflect UV rays and work immediately when put on the skin.

How to Apply

“The best technique is to apply sunscreen first, then apply makeup on top,” Scheiner says. “The product that provides the most protection defines the extent of the protection. So if you use an SPF 45 mechanical sunblock with titanium dioxide and/or zinc oxide first, and then apply makeup with SPF 20, the effective SPF will be 45.”

If you are spending the day outdoors or have been swimming, reapply sunscreen every2–3 hours.

Fake It, Don’t Bake It!

Still craving sun-kissed skin? Opt for a natural self-tanner. The active ingredient in most self-tanners is dihydroxyacetone (DHA), a color additive derived from beet or cane sugar that darkens the skin by reacting to the amino acids in the skin’s top layer. The percentage of DHA that a product contains determines how dark the skin will become. “There is some controversy over the safety of spray tans, as the DHA can be inhaled into the lungs,” says Imahiyerobo-Ip. “I recommend sticking with self-tanning lotions, foams, and creams.” For best results, start with freshly exfoliated skin and apply evenly with a light hand—and then get glowing!

Vitamin D3 Summer Shortfall?

Since our bodies make vitamin D when we’re exposed to the sun, it might seem as though we don’t need to worry about getting enough during summer months, but beware. For one thing, sunscreen blocks the process, and a tan, or naturally darker skin, reduces vitamin D synthesis. A study of nearly 1,000 sun-loving Brazilians, living close to the equator, found that most had vitamin D levels below optimum.

Vitamin D has far-reaching benefits, including stronger bones, a healthier heart, better immune function, and healthier lungs. Among toddlers, healthy levels of the vitamin correlate with more muscle mass and less body fat.

The best way to identify individual needs is with a blood test, available through medical and naturopathic physicians. Optimum levels range between 30 and 60 ng/mL. Below 20 ng/mL is considered deficient and up to 100 ng/mL is considered safe.

Can you take too much? When Mayo Clinic researchers examined more than 20,000 vitamin D test results and safety of supplementation, they found only one case of toxicity, in a patient who had taken extremely high doses: 50,000 IU daily for more than three months. The Institute of Medicine, at the National Academy of Sciences, recommends an upper limit of 4,000 IU daily.

—Vera Tweed

Physical blockers contain two main ingredients, zinc and titanium oxide, which are natural minerals that block the UV rays of the sun.

UVA vs. UVB

UVA: While UVA rays do not cause sunburn, they can lead to skin cancer, as well as premature aging and darkening of the skin. UVA rays penetrate deeper into the skin than UVB ones.

UVB:These rays, which are filtered by the ozone, cause sunburn and increase the risk of melanoma and other skin cancers.

Ingestible Sunscreen?

Can something you eat or take in supplement form protect you from sun damage? Possibly. The dietary supplement sector has zeroed in on several promising nutrients that may do just that. These include lycopene (a carotenoid found in tomatoes and other foods); beta carotene (found in carrots and green vegetables); astaxanthin (a carotenoid found in certain algae); and the colorless carotenoids phytoene and phytofluene (found in numerous fruits and vegetables including tomatoes).

Carotenoids are not the only compounds that help shield the skin from UV damage. Researchers at the Memorial Sloan Kettering Cancer Center in New York have been testing an extract of the antioxidant-rich tropical fern Polypodium leucotomos, which has a long history of use in South America as a treatment for psoriasis and dermatitis.

Across the pond, researchers at King’s College in London are studying algae uniqueto Great Barrier Reef coral. The algae are rich in mycosporine amino acids (MAAs) that provide a sunscreen-like benefit for fish and other organisms living in the surrounding clear, shallow waters.

Dermatologists say that although the science looks intriguing so far, oral sunscreens have not been proven to be as safe or effective as topical sunscreens—yet.

Our picks for healthy & natural sun protection

Babo Botanicals Daily Sheer
Sunscreen Extra Sensitive for Face SPF 40

Badger
Baby Chamomile & Calendula Broad Spectrum SPF 30

Derma e
Antioxidant Natural Sunscreen Oil-Free Face 30 SPF

Goddess Garden
Organic Everyday Natural Sunscreen Continuous Spray

Solgar
Astaxanthin 5 mg Softgels