This newsletter from Phuket health and travel will provide you with some information about the most common problem for tourists here in Phuket, to much sun.
The sun protection products mentioned from La Roche-Posay are now available at the pharmacy at Bangkok Phuket Hospital
Eight big sunscreen mistakes
Once limited to sticks, oils and chalky creams, sunscreens now come in lotions, gels, sprays, wipes, mousses and powders. A sun protection factor, or SPF, also is found in foundations, moisturizers, bug sprays, laundry detergent and even a product that protects against jellyfish stings. Still, skin cancer continues to rise, and part of the problem is the "I'm covered" attitude that sunscreens seem to foster, dermatologists say. Here are the main mistakes people make:
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Not knowing what SPF means: SPF is a multiplier that describes how much time a sunscreen allows a person to spend in the sun before getting burned by UVB rays. A product with an SPF of 15, the minimum doctors advise, lets you stay in the sun 15 times longer. The SPF says nothing about how well a sunscreen protects against UVA light.
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Not knowing what ingredients to look for: Among U.S.-approved sunscreen ingredients, many protect against UVB light: benzones (like dioxybenzone and oxybenzone), for example, and the cinnamates (like octyl methoxycinnamate). But only one, avobenzone (Parsol 1789), specifically absorbs UVA light. The sunblocks zinc oxide and titanium dioxide reflect UVA and UVB light. But products that combine avobenzone with zinc oxide, titanium dioxide or one of the ingredients that absorb UVB light are even better.
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Skimping: To get the SPF advertised on a bottle takes a full teaspoon slathered on the face and enough to fill a shot glass rubbed over the body. Yet people typically apply only 20 percent to 60 percent of that, a 2002 study found. The ears, the neck, the hands, the feet and even bald patches on top of the head are commonly missed sites.
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Applying it too late: Most sunscreens take 15 to 20 minutes to start working because they have to be absorbed by the skin first.
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Not reapplying: There's no such thing as all-day protection because the active ingredients in sunscreens degrade in the sun after about two hours. (That is why you sometimes hear that an SPF of 45 is no more useful than an SPF of 30; both need to be reapplied after two hours.)
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Not wearing it daily: Many people remember to wear sunscreen only at the beach. But subtle everyday exposure to UV light can add up to wrinkling or cancer.
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Continuing to use old products: Most sunscreens have a shelf life of three years. (If you have kept one around that long, however, you are probably not using enough.) Products lose their potency even faster if bottles are left out in the sun or stashed in a hot car, where light and heat can degrade them.
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Not taking medications into account: Antibiotics such as tetracycline can make the skin more photosensitive, leaving it more vulnerable to UV damage. So, too, can thiazide diuretics, drugs included in some blood pressure medicines.
Mexoryl what is that?
Only a few insiders most of them women know.
Mexoryl, is a new sunscreen ingredient that is thought to be particularly useful in preventing wrinkles.The earliest sun lotions launched in the 1930s filtered only UVB. At that time no one suspected the extent to which UVA contributed to sun damage.
Today we know that overexposure to any type of ultraviolet rays can produce not only sunburn but premature aging, reduced elasticity of the skin, other degenerative phenomena and certain types of cancer.
Mexoryl has been used since 1993 in sunscreen lotions sold in Canada and Europe but in the U.S. it is still waiting for FDA approval.
So far the FDA has approved only three ingredients protective against UVA: zinc oxide, titanium dioxide and avobenzone (trade name Parsol 1789).But Mexoryl seems more effective than any of these at protecting against UVA light. In 2000 Canadian and French researchers slathered six brands of sunscreen and sunblock on the backs of volunteers and exposed their skin to a UV sunlamp for 15 minutes. The product containing Mexoryl (along with avobenzone, titanium dioxide and other ingredients) was more than twice as effective in protecting against UVA light as any of the others. The study was published in the Journal of the American Academy of Dermatology.
Sunscreen labels often advertise "full spectrum" or "broad spectrum" properties, meaning that they block both UVA and UVB rays. But products can make this claim without specifying how well they protect against UVA rays. And because the familiar sun protection factor (SPF) measurements apply only to UVB blockage, consumers have no handy way to gauge the effectiveness of UVA filters.
The difference between UVA and UVB light is a matter of wavelength. UVA rays come in longer wavelengths (320 to 400 nanometers), so they pass through the outer layer of skin, rather than burning it as do the shorter UVB rays (290 to 320 nanometers).UVA rays penetrate deep into the dermis, or lower layer of skin, where they can break down collagen and other proteins that keep the skin plump and firm. Deeper penetration and deeper damage is believed to be associated with premature aging in the skin.
The UVA rays also can damage cells and DNA in the dermis, decrease the skin's immunity and generate harmful free radicals. Though the exact mechanisms remain unclear, doctors assume these actions explain why UVA exposure also is associated with skin cancer.Unlike UVB light, prevalent only when the sun is high in the sky -- between 10 a.m. and 4 p.m. during summer -- UVA light is virtually inescapable. "It's present in the same amount from sunup to sundown, 365 days a year, totally independent of climate conditions. That means it not only penetrates car windows and T-shirts, but it also reaches the skin during fog, rain and even blizzards. Mexoryl is also very sturdy compared with other UVA filters, which tend to decompose when exposed to sunlight.
