
Making Sense of Sunscreen Products
SPF stands for sun protection factor. The SPF numbers on a product can range from as low as 2 to as high as 60. These numbers refer to the product's ability to screen or block out the sun's burning rays.
Sun protection is simply guarding a body against the adverse effects of sunlight. Aside from the hazards of heat, the sun poses the danger of sunburn, which can permanently damage the skin and cause skin cancer, precancerous changes in the skin, as well as premature wrinkling, and signs of aging. Exposure to ultraviolet rays from the sun is a known risk factor for the development of both melanoma and nonmelanoma skin cancers.
A survey conducted by the U.S. Centers for Disease Control and Prevention (CDC) and published in 2015 showed that despite public health warnings, only around one-third of Americans use sunscreen regularly. Women were more likely than men to use sunscreen on the face, and sunscreen use was also more common in higher socioeconomic groups.
The best ways to avoid sunburn are to do the following:
SPF stands for sun protection factor. The SPF numbers on a product can range from as low as 2 to as high as 60. These numbers refer to the product's ability to screen or block out the sun's burning rays.
Sunscreen, which is a form of sun protection, is any substance or material that protects the skin from UV radiation.
Sunscreens can be applied to the skin and are available in the following forms:
Other forms of sun protection include:
Many facial moisturizers and cosmetics products also offer some degree of sun protection.
SPF, an abbreviation for sun-protection factor, is a number such as 15, 30, or 50 that indicates the degree of sunburn protection provided by sunscreens. SPF is related to the total amount of sun exposure rather than simply the length of sun exposure. It is a common mistake to assume that the duration of effectiveness of sunscreen can be calculated simply by multiplying the SPF by the length of time it takes for him or her to suffer a burn without sunscreen because the amount of sun exposure a person receives is dependent upon more than just the length of time spent in the sun.
The amount of sun exposure depends upon several factors, including:
A common mistake is applying too little sunscreen, which can drastically reduce the effective SPF of the product. About 1 ounce (5-6 teaspoons) of sunscreen is recommended to cover the entire body. Further, sunscreen must be reapplied every two hours when staying outdoors for a prolonged period. Sunscreen should also be applied for at least 30 minutes before going outdoors.
A major limitation of the SPF value is that these numbers are determined from a test that measures protection against sunburn caused by ultraviolet B (UVB) radiation. Therefore, SPF values only indicate a sunscreen's UVB protection and do not provide any information on the product's effectiveness in blocking the ultraviolet A (UVA) rays that contribute to the development of skin cancers. Rulings issued in 2011 require more accurate labeling of sunscreen products than was required in the past.
Some sunscreens protect against only one type of ultraviolet radiation: ultraviolet-B (UVB). Others protect against both types of ultraviolet radiation that reach the earth's atmosphere from the sun: ultraviolet-B and ultraviolet-A (UVA).
Sunscreens that protect against both UVA and UVB, and are thus classified as "broad spectrum," are recommended for everyone. There are new regulations in the labeling of sunscreen products that allow consumers to better understand the degree of protection offered by a given product.
Physical sunscreens containing zinc oxide or titanium dioxide protect against UVB and UVA. However, zinc oxide blocks more UV radiation than titanium dioxide and, therefore, is the preferred ingredient.
Some chemical sunscreens can also block UVA rays. Octocrylene is a chemical known as a cinnamate that has both UVA- and UVB-absorbing properties, and the benzophenones (such as avobenzone) can also absorb both UVA and UVB rays.
In July 2006, the U.S. FDA approved an over-the-counter (OTC) sunscreen preparation known as Anthelios SX that contains the UVA filter ecamsule. Ecamsule is a potent UVA-blocking compound that has been sold in sunscreen products in Canada and Europe since 1993. Because in the U.S., sunscreens are regulated by the FDA as are drugs, it is typically more difficult to gain approval for newer sunscreen products than in countries where sunscreens are legally cosmetics products.
It's a good general rule to apply sunscreen very liberally. Those who skimp won't receive full protection. Most people do not use enough sunscreen and do not apply it frequently enough. The sunscreen should be applied about a half hour before going outside to allow time for the sunscreen to soak in and take effect. If you're not sure, it's better to over-apply than to apply too little. There is no damage or danger associated with using too much sunscreen.
Many women use foundation makeup that contains sunscreen. However, this should be used as an extra layer of protection rather than the only source of sunscreen, because the amount of makeup that is needed usually is far below the amount that would be needed for effective sun protection.
Applying sunscreen only on sunny days or when it is hot is a common mistake. While the sun may be stronger in summer, UV rays can penetrate clouds and fog and can cause damage even when the sun isn't bright.
Yes, water and perspiration can wash off sunscreen. Sunscreens must be reapplied frequently. Therefore, sunscreen should be reapplied at least every two hours when staying outdoors for a prolonged period and after swimming, bathing, perspiring heavily or drying off with a towel or handkerchief. Water- and perspiration-resistant sunscreens are available. However, even their protection will not last indefinitely, and they should be reapplied frequently, as well.
PABA (para-aminobenzoic acid) was one of the original UVB-blocking products in sunscreens. Some people developed a skin reaction to this chemical, and it was also found to stain clothing. Over the years, PABA has been refined and modified into newer ingredients known as glycerol PABA, padimate A, and padimate O, all of which are UVB-blocking sunscreen ingredients. Other ingredients in sunscreens may also increase the risk of skin reactions in certain people.
Anyone can determine the suitability of a particular sunscreen without risk of serious harm by:
As a general rule, babies 6 months of age or younger should not have sunscreen applied to their skin because their bodies may not be capable of tolerating the chemicals in sunscreens. Instead, they should be kept away from sun exposure.
Everyone over 6 months of age should use sunscreen regularly unless they and their doctors decide it would be better to protect the skin in other ways. Even with sunscreen use, wearing protective clothing and eyewear to shield against UV rays is recommended. Sunscreen alone should not be regarded as complete protection from all UV radiation.
In the past, manufacturers' claims on sunscreen packaging were largely unregulated. However, in 2011, the U.S. Food and Drug Administration (FDA) issued labeling regulations for over-the-counter sunscreens. According to these FDA guidelines, sunscreen labels were prohibited from making claims that are considered unproven or absolute such as "waterproof" and "all-day protection." Earlier regulations for sunscreens concerned protection against sunburn, which is primarily caused by ultraviolet B (UVB) radiation from the sun, and did not address ultraviolet A (UVA) radiation, which is a cause of skin cancers and early skin aging.
According to the FDA ruling, all products that claim to provide broad-spectrum sun protection must comply with the following rules:
The Environmental Working Group, in a 2015 study of over 1,700 sun-protection products, released a report stating that 80% of these products offer inferior sun protection or contain "worrisome" ingredients. They also note that most SPFs max out at about SPF 50 even though many sunscreens on the market claim to have much higher SPF ratings.
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As described above, there is no such thing as a true "sunblock." This is a marketing term formerly used to label sunscreens with high SPF. Manufacturers can no longer identify their products as sunblocks because these claims are inaccurate exaggerations. No sunscreen can completely block the sun's rays.
No, some don't. Tanning products such as self-tanners that don't contain sunscreen are required by the FDA to carry a warning label alerting consumers to the dangers of unprotected sunbathing.
Only those that provide 100% protection against UVA and UVB radiation, as stated on the label at the time of purchase, should be worn for protection.
Yes, UV radiation, though not as intense in the winter, still poses a threat, especially when rays reflect off snow. Skiers should also note that the degree of exposure to the sun's radiation increases by 4% for every 1,000-foot increase in altitude. There is no safe time of year when it comes to UV radiation. The same applies to weather conditions. Even on a cloudy day, 80% of the sun's ultraviolet rays pass through the clouds and reach the earth.
No, they are only one part of a complete sun protection program. An effective program also includes limiting sun exposure and wearing protective clothing.
Yes, sunscreens can lose effectiveness over time. Many sunscreen products are labeled with an expiration date to signal the limit of the product's effectiveness and stability. Sunscreens are typically designed to be stable for three years. Storing sunscreen in the heat, however, can cause the active ingredients to lose effectiveness faster than storing it in a cool place. Discard any sunscreen that is past the stamped expiration date, and if you purchase sunscreen without such a date, write the month and year of purchase on the bottle.
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Heat rash remedies include OTC creams and sprays. Usually heat rash resolves when the skin is cooled sufficiently. Medical treatment may be necessary if the sweat glands become infected.
There are many natural and home remedies that are thought to relieve the symptoms ofa sunburn. Check out our top 30 tips to cool that sunburn, for example drink lots of water, juice, or sports drinks; apply a cool compress containing Burow's solution; coconut oil can be used as a moisturizer after sunburn pain has stopped; apply topical over-the-counter (OTC) 1% hydrocortisone cream; and take OTC pain relievers like NSAIDs (nonsteroidal anti-inflammatory drugs) such as ibuprofen (Advil, Motrin) or naproxen (Aleve).