Sunscreen Buying Guide
Excessive sun exposure causes photoaging—a cumulative process through which our skin becomes wrinkled, rough, dry, and discolored. Even more concerning is that too much exposure can cause skin cancer. Yet, time in the sun is often part of a healthy and active lifestyle, and our bodies need sun in order to make vitamin D, a biomolecule with many essential functions. Fortunately, an array of sunscreen products are available that can help protect your skin when spending time outdoors. Keep the following points in mind as you consider sunscreen products:
- Even if you are trying to get a small amount of sun exposure to allow your body to make vitamin D—experts agree that 15 minutes of early morning or late afternoon sun is plenty for most people—minimize or avoid midday sun, when rays are the strongest (10 a.m. to 2 p.m.).
- When in the midday sun, wear a broad-brimmed hat and cover skin with clothing, whenever possible. A plain white t-shirt offers an SPF of about 8 (not much). Darker colors typically offer more protection.
- Use a water-resistant sunscreen if swimming or sweating.
- Reapply sunscreen at least every two hours, or more often, according to activity level and label directions.
- If your skin is never exposed to sunlight without sunscreen, consider taking a vitamin D supplement to avoid deficiency.
- Sunscreens that only block ultraviolet B (UVB) radiation are fine for preventing sunburn, but don't protect against skin cancer or early photoaging.
- Sunscreens that block both UVA and UVB radiation and have an SPF of 15 or higher are labeled “broad spectrum” and may help protect against more of the harmful effects of sunlight.
- Healthcare professionals generally recommend a broad-spectrum SPF of 30 or higher.
SPF defined
SPF—“sun protection factor”—is a measure of the time it would take a person to burn in the sun without sunscreen vs. the time it would take them to burn with sunscreen. The scale is not linear, so SPF 30 does not offer twice the protection of SPF 15: SPF 15 blocks about 94% of UV rays, SPF 30 blocks 97%, and SPF 45 product blocks 98% of rays, but only for a couple of hours. After that, all sunscreens, regardless of SPF, must be reapplied for full protection.
Another kind of burn risk
Spray-on sunscreens often contain flammable ingredients. Several incidents of significant burns in people wearing spray-on sunscreens near open flames have led the FDA to issue a warning about the use of these products, directing people to stay away from flames, sparks, and ignition sources while applying and wearing spray-on sunscreens.
- Chemical sunscreens
What they are: Chemical sunscreens contain ingredients that react with the sun’s radiation as it hits your skin, preventing the rays from harming skin.
Why to buy: Chemical sunscreens are found in many water-resistant products because they tend to have more “staying power” than other sunscreens. Chemical sunscreens tend to be less expensive and come in easy-to-apply options, such as lotions, gels, sprays, wipes, and sticks.
Things to consider: Some people have allergic reactions to certain chemical sunscreen ingredients. Common offenders include PABA, cinnamates, oxybenzone, and salicylates. If you’ve had skin reactions to chemical sunscreens, try a brand that is free of the chemicals to which you've reacted (if known). Also, try fragrance- and oil-free products to minimize skin reactions.
When sunscreens wash off the skin, they enter the environment. Some chemicals used in sunscreens have been shown to damage coral, and to accumulate in fish and other marine life, where they act as hormone disrupters.
In 2011, the FDA expressed concerns about spray-on sunscreens, especially for children, since it is unclear whether this method of application leads to inhalation of unsafe chemicals, or adequately protects against sun damage.
- Physical sunscreens
What they are: Physical sunscreens contain finely ground mineral particles, such as zinc and titanium salts, that form a physical “shield” against the sun’s radiation. The two most common physical sunscreen ingredients are zinc oxide and titanium dioxide.
Why to buy: Physical sunscreens are less likely to cause skin irritation and rashes than chemical sunscreens, making them an attractive option for young kids and adults with sensitive skin. For consumers who prefer to reduce chemical exposure, many health experts advise using physical sunscreens and many pediatricians recommend them for children under two years.
Things to consider: Physical sunscreens, when properly applied, usually give a white appearance to the skin. To reduce this effect, some manufacturers have developed more transparent zinc oxide and titanium dioxide sunscreens using so-called nanoparticles. Although concerns have arisen regarding the potential harms of nanoparticles of zinc and titanium salts, the research so far indicates that they do not pose health dangers.
Physical sunscreens are likely to cost more by volume than chemical sunscreens. In addition, some people find that physical sunscreens “sweat off” more easily, which means they have to be reapplied more frequently to ensure protection.
Keep in mind that even physical sunscreens can contain fragrances or oils, both of which may irritate skin.
- All-natural sunscreens
What they are: All-natural sunscreens contain only physical sun-blocking ingredients, and may contain herbs and other plant extracts to soothe the skin as well. They do not contain synthetic chemicals, fragrances, or oils.
Why to buy: For those who have children with extremely sensitive skin or very young children, all-natural sunscreens can be a good option.
Things to consider: Because these sunscreens contain physical sun-blocking agents, all of the concerns associated with physical sunscreens apply to all-natural sunscreens. All-natural sunscreens are not as resistant to water and sweat, so a single application may not provide enough protection for a long day at the beach or pool. Be sure to reapply them often to maximize the benefits.
- Long-wear and water-resistant sunscreens
What they are: Long-wear and water-resistant sunscreens are designed to offer the best protection in active situations, such as during exercise or when swimming. Product labels will tell you whether they have been rated for 40 or 80 minutes of protection. After that time they must be reapplied for full sun protection.
Why to buy: For active people, long-wear and water-resistant products may be the only type of sunscreen that truly protects against sun damage. If you tend to sweat a lot or like to swim, these products can be a good option.
Things to consider: Many people find long-wear sunscreens feel “sticky” or “greasy” on the skin. While this may be annoying, this is the reason these products can stand up to sweat and water while still offering sun protection. Labeling requirements allow a product to be called water “resistant,” but not “water-proof” or “sweat-proof.”
- Sunscreens for kids
What they are: Sunscreens marketed for kids can contain chemical or physical sun-blocking ingredients, or sometimes a combination of the two. These products are usually designed to be safer and gentler on the skin, and often do not contain the chemical ingredients most likely to cause irritation or allergic reactions or pose health harms (PABA, cinnamates, oxybenzone, and salicylates).
Why to buy: Try a kid-friendly sunscreen for your family, especially for children younger than 12 years. The most kid-friendly products contain only physical sun-blocking ingredients.
Things to consider: There are no regulations guiding the use of the words “children,” “kids,” and “family” in product names or marketing—in some cases, these products are no different than those marketed for general use. Sunscreens marketed as kid-friendly tend to cost more, so be sure the formula is truly gentle and safe.
Sunscreens are not recommended for babies under six months old. Babies should be protected from the sun by keeping them in the shade or covered up if they have to be in the sun.