Sun Block
There are literally thousands of sunscreen products to choose from. They vary in feel, scent, color, water resistance and how well they rub in. The whole point of sunscreens is to prevent UV radiation from damaging your body. The best sunscreen for you, is one that meets your needs (i.e. waterproof or not), doesn’t irritate your skin, offers the protection you require based on the UV Index for where you are, and that you like the scent and feel of. Finding a sunscreen you really like and protects you can be a challenge. Some manufacturers change their formulas from one year to the next, meaning your favorite product last year might not be your favorite this year. This is all based on personal preferences and experiences, and we can’t tell you what you’ll like, but we can show you some important things to know about sunscreen.
So what are sunscreens?
Sunscreen refers to products that allow the Sun’s rays to penetrate the skin but filter some of the radiation in the ultra violet spectrum. The UV rays get altered to a safer wavelength and are released. The chemical interaction between the sunscreen and UV allows the sunscreen to absorb the UV before it penetrates the skin. Sunscreen offers protection from UV-A and UV-B, however sunscreen ingredients have the ability to deteriorate at a faster rate once exposed to sunlight, hence some radiation is able to penetrate to the skin. Some sunscreen products offer no protection against UV-A radiation whatsoever. Products often contain a mixture of physical and chemical block ingredients. UVB is the chief culprit behind sunburn, while UVA rays, which penetrate the skin more deeply, are associated with wrinkling, leathering, sagging, and other light-induced effects of aging (photoaging). They also exacerbate the carcinogenic effects of UVB rays, and increasingly are being seen as a cause of skin cancer on their own. Sunscreens vary in their ability to protect against UVA and UVB.
So what are Sunblocks?
Sunblock works by preventing the Suns rays from reaching your skin – either by reflecting them away or absorbing them, changing there structure and releasing them. Sunblock used to sit on top of your skin and had a white appearance. With nano technology (making things really small) some sun blocking ingredients are now invisible to the eye, so you dont get that white ghost look. The main active ingredients in sunblock are titanium dioxide and zinc oxide.
Sunscreen or Sunblock?
Depending on the ingredients used, sunscreen and sunblock can both provide UVA and UVB protection. The reason for the different names comes from how they work, which depends on the ingredients used. Sunblock (until recent nano technology) used to sit on top of the skin forming a barrier that would block UV rays from reaching the skin. Sunscreens work by being absorbed into the skin, when UV rays reach the skin the sunscreen ingredients will screen out UV rays by changing them into less harmful energy. Today the terms ‘sunscreen’ and ‘sunblock’ are mostly used for marketing purposes. Government bodies and health organizations would like to see the term sunblock discontinued as they feel it gives a false sense of safety in the Sun. Whats more important than the labeling on the front of the bottle, is the ingredients on the back. Check them out.
What does SPF mean?
SPF stands for Sun Protection Factor and shows to what degree a product prevents sunburn. Since sunburn is caused by UVB radiation, SPF rating give no indication of how well a product will protect you from UVA radiation (responsible for skin aging and skin cancer). A higher value means you get more protection. As sunburn is caused by UVB radiation SPF is only a measure of how much UVB is blocked, not how much UVA. So while you may be using the highest SPF available, you are still completely vulnerable to UVA radiation – which causes skin cancer and skin aging. For protection against both UVA and UVB rays you will need a ‘broad spectrum’ product.
Most sunscreens with an SPF of 15 or higher do an excellent job of protecting against UVB. SPF — or Sun Protection Factor — is a measure of a sunscreen’s ability to prevent UVB from damaging the skin. Here’s how it works: If it takes 20 minutes for your unprotected skin to start turning red, using an SPF 15 sunscreen theoretically prevents reddening 15 times longer — about five hours.
Another way to look at it is in terms of percentages: SPF 15 filters out approximately 93 percent of all incoming UVB rays. SPF 30 keeps out 97 percent and SPF 50 keeps out 98 percent. They may seem like negligible differences, but if you are light-sensitive, or have a history of skin cancer, those extra percentages will make a difference. And as you can see, no sunscreen can block all UV rays. But there are problems with the SPF model: First, no sunscreen, regardless of strength, should be expected to stay effective longer than two hours without reapplication. Second, “reddening” of the skin is a reaction to UVB rays alone and tells you little about what UVA damage you may be getting. Plenty of damage can be done without the red flag of sunburn being raised.
What SPF should I use?
When choosing an SPF rating, keep in mind that doubling the SPF value doesn’t mean you get double the protection. SPF 15 will block the majority of UVB rays, SPF will block more, and anything over SPF 30 doesn’t really protect you much more than an SPF 30 product.
SPF 15 blocks roughly 93% of UVB.
SPF 30 blocks roughly 97% of UVB.
What type of sunscreen should I use?
The answer depends on how much sun exposure you’re anticipating. In all cases we recommend a broad-spectrum sunscreen offering protection against both UVA and UVB rays. Many after-shave lotions and moisturizers have a sunscreen (usually SPF 15 or greater) already in them, and this is sufficient for everyday activities with a few minutes here and there in the sun. However, if you work outside or spend a lot of time outdoors, you need stronger, water-resistant, beachwear-type sunscreen that holds together on your skin. The “water resistant” and “very water resistant” types are also good for hot days or while playing sports, because they’re less likely to drip into your eyes when you sweat. However, these sunscreens may not be as good for everyday wear. They are stickier, don’t go as well with makeup, and need to be reapplied every two hours.
Many of the sunscreens available in the US today combine several different active chemical and physical sunscreen ingredients in order to provide broad-spectrum protection. Usually, at least three active ingredients are called for. These generally include PABA derivatives, salicylates, and/or cinnamates (octylmethoxycinnamate and cinoxate) for UVB absorption; benzophenones (such as oxybenzone and sulisobenzone) for shorter-wavelength UVA protection; and avobenzone, ecamsule (MexorylTM), titanium dioxide, or zinc oxide for the remaining UVA spectrum.
Sunscreen Effectiveness
How well you are protected depends on what product you use and how you use it. If you are constantly going in and out of the ocean or pool, sunscreen may need to be re-applied after every dip depending on how waterproof it is. Heavy sweating and toweling off can also wear off a sunscreen.
Application
General instructions that apply to most sunscreens (this may be different for the products you use, so always read the instructions.
– apply to dry skin
– make sure to cover your face, ears, neck and shoulders
– apply 15 to 30 minutes before going in the Sun
– re-apply after toweling off, swimming, or heavy sweating
– re-apply roughly every 2 hours
Sunscreen for Babies and Kids
The main reason for creating sunscreens for babies and kids is to account for their sensitive skin, and to prevent them hurting their eyes if the sunscreen manages to find it’s way there, which it usually does. Sunscreens for babies and kids often are quite similar to those provided for adults minus a few ingredients that may irritate childrens eyes and sensitive skin. Common ingredients that are omitted for this reason are preservatives, dyes, and artificial fragrances. Titanium dioxide and zinc oxide based sunscreens are recommended for babies and children.
Who should use sunscreen?
Anyone over the age of six months should use a sunscreen daily. Even those who work inside are exposed to ultraviolet radiation for brief periods throughout the day, especially if they work near windows, which generally filter out UVB but not UVA rays. Children under the age of six months should not be exposed to the sun, since their skin is highly sensitive to the chemical ingredients in sunscreen as well as to the sun’s rays. Shade and protective clothing are the best ways to protect infants from the sun.
How much sunscreen should I use and how often should I put on?
To ensure that you get the full SPF of a sunscreen, you need to apply 1 oz – about a shot glass full. Studies show that most people apply only half to a quarter of that amount, which means the actual SPF they have on their body is lower than advertised. During a long day at the beach, one person should use around one half to one quarter of an 8 oz. bottle. Sunscreens should be applied 30 minutes before sun exposure to allow the ingredients to fully bind to the skin. Reapplication of sunscreen is just as important as putting it on in the first place, so reapply the same amount every two hours. Sunscreens should also be reapplied immediately after swimming, toweling off, or sweating a great deal.
Common sunscreen myths
Wearing sunscreen can cause vitamin D deficiency.
There is some controversy regarding this issue, but few dermatologists believe (and no studies have shown) that sunscreens cause vitamin D deficiency. Also, vitamin D is available in dietary supplements and foods such as salmon and eggs, as well as enriched milk and orange juice.
If it’s cold or cloudy outside, you don’t need sunscreen.
This is not true. Up to 40 percent of the sun’s ultraviolet radiation reaches the earth on a completely cloudy day. This misperception often leads to the most serious sunburns, because people spend all day outdoors with no protection from the sun.
Eighty percent of your sun exposure comes as a child, so it’s too late to do anything now.
It appears that this universally promoted idea was based largely on a misinterpretation. A recent multi-center study showed that we get less than 25 percent of our total sun exposure by age 18. In fact, it is men over the age of 40 who spend the most time outdoors, and get the highest annual doses of UV rays. And since adult Americans are living longer and spending more leisure time outdoors, preventing ongoing skin damage will continue to be an important part of a healthy lifestyle.
Buy a high-quality product with an SPF of 15 or higher; check its ingredients to make sure it offers broad-spectrum protection; and decide whether it works better for everyday incidental use or extended outdoor use. Finally, look for The Skin Cancer Foundation’s Seal of Recommendation, which guarantees that a sunscreen product meets the highest standards for safety and effectiveness. Once you choose the right sunscreen, use it the right way. But remember, you should not rely on sunscreen alone to protect your skin against UV rays; it is just one vital part of a complete sun protection program. By following our Prevention Guidelines, you can lower your risk of developing skin cancer, while helping your skin look younger, longer.
