December 8th, 2011 by John Di Saia, M.D. in Research
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“According to that study, nearly half of the 500 most popular sunscreens may actually increase the speed at which malignant cells develop and spread skin cancer such as melanoma.
Why? Because they contain Vitamin A, an ingredient that was added to sunscreen formulations because it’s an antioxidant that slows skin aging.
This isn’t necessarily new information….as some studies suggest “that vitamin A might have some phototoxicity.”
Source: health.msn.com/health-topics/skin-and-hair/articlepage.aspx?cp-documentid=100260739
Take it easy folks. One study on the effects of Vitamin A on skin cancers in animals does not invalidate sunscreen use. We don’t really need Vitamin A in sunscreens though. We need good blockers of UVA and UVB at an SPF of at least 30.
*This blog post was originally published at Truth in Cosmetic Surgery*
July 20th, 2011 by Kay Cahill Allison in Health Tips
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It doesn’t make sense: If sunlight causes cancer, why are human beings so drawn to it, flocking to sunny beaches for vacation time and hoping for sunshine after a rainy spell?
One answer, says David Fisher, chief of dermatology at Harvard-affiliated Massachusetts General Hospital in Boston, may be that humans are literally addicted to sunshine so our skin can make vitamin D. New evidence suggests that we get the same kick out of being in the sun that we get from any addictive substance or behavior. It stimulates the so-called “pleasure center” in the brain and releases a rush of feel-good chemicals like endorphins.
So there may be more than a desire to look good in a tan behind the urge to soak up the sun’s rays. This craving may be a survival mechanism that evolved over thousands of years because humans need vitamin D to survive. Skin makes this crucial vitamin when it is exposed to sunlight. There isn’t much vitamin D in food (except in some of today’s fortified foods) so the human brain rewards us with a rush of pleasure when we seek out the sun and get vitamin D.
Seeking sunshine can be downright dangerous. As Fisher points out, Read more »
*This blog post was originally published at Harvard Health Blog*
July 3rd, 2011 by Jeffrey Benabio, M.D. in Health Tips
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Life is really simple, but we insist on making it complicated. -Confucius
This is certainly true of sunscreens. “Broad spectrum, UVA, UVB, avobenzone, oxybenzone, parsol, sensitive skin, titanium dioxide, SPF 15, 30, 45, 50, 55, 60, 70, 75, 100, 100+, waterproof, sweatproof, spray, cream, lotion, antioxidant…”
We spend about $700 million in sunscreens every year, and many people don’t have a clue as to what’s good or bad, or a waste of money. The Food and Drug Administration has been meaning to help you out with this problem for a while now. Actually for over 30 years (who says nothing gets done in government?). The F.D.A. has made a final decision on sunscreen labels. They’ve sought to make labels simple and accurate to help you choose the right one:
1. The sunscreen must protect against both UVA and UVB rays; that is, it must be broad spectrum.
2. To be labelled as “protecting against skin cancer,” the sunscreen must be an SPF of at least 15. The labels will likely be capped at SPF 50 because SPFs greater than 50 seem to be of little additional benefit.
3. Sunscreens can no longer be labelled as “waterproof” or “sweat proof,” as neither is physically possible, therefore, rendering the claim “misleading.” Sunscreens will be labelled as effective in water for 40 minutes or 80 minutes which is accurate and much more useful.
This simple system should help consumers make better choices, but some say the F.D.A. didn’t go far enough. They did not comment on the safety of various sunscreen ingredients. They have also not loosened up enough to allow for other sunscreens that are widely used in Europe to be sold here in the U.S.
Do you think the F.D.A was too strict or didn’t go far enough?
Photo: Wandering Magpie, Flickr
*This blog post was originally published at The Dermatology Blog*
July 1st, 2011 by Dr. Val Jones in Audio, Health Tips
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A Pterygium
Dermatologists have done a great job promoting sun safety. We all know that we should use sunscreen or sunblock to avoid burns, and to reapply it religiously when we plan to be outdoors for long periods of time. But how often do we think about protecting our eyes from the same UV rays?
A dear friend of mine has been on a long-term medicine that makes her skin especially sun-sensitive. She did not take sufficient precautions to protect her eyes from UV radiation (though she always wore sunscreen on her skin), and she developed a pterygium that looks just like the photograph above. Her condition reminded me of the importance of eye protection, and I thought I’d offer you 5 excellent reasons to start shielding your eyes from the sun. UV protection is critical for avoiding:
1. Photokeratitis. Photokeratitis is essentially a sunburn of the front layer (cornea) of your eyeball. If you’ve ever had a burning sensation in your eyes after a long day at the beach, or in the snow, you may have burned your eyes. Just as skin sunburns are painful and take a few days to calm down, eye pain can be very uncomfortable. But worse than the temporary discomfort is the increased long-term risks of pterygia, cataracts, and other eye conditions (see below).
2. Pterygia. Pterygia are overgrowths of corneal tissue that can grow across the iris and pupil. They can be cosmetically unsightly, and can block vision if they grow large. They are caused almost exclusively by UV damage, and are most common in people who live near the equator (because their exposure to UV radiation is highest). Surgery is the only known treatment for pterygia, though as many as 50% grow back, and surgical divets in the cornea can cause visual problems.
3. Cataracts. Cataracts are opacities of the eye lenses that lead to partial or total blindness. The exact mechanism by which they occur is unclear, though we know that sun exposure contributes to their development. Cataracts are the number one cause of blindness in the world.
4. Skin Cancers. Basal cell carcinoma (BCC) is a type of skin cancer that primarily develops on skin that has been sunburned, especially in childhood. Melanoma is a deadly form of skin cancer that is much rarer than BCC, but also most commonly develops on skin that has been burned. Squamous cell carcinoma (SCC) is the least invasive type of skin cancer, and usually develops on skin that has had the largest total amount of sun exposure over a lifetime. People who don’t protect the thin eye skin and lids from UV radiation (beginning in childhood) are more likely to develop cancer around the eyes
5. Macular Degeneration. Exposure to the sun’s UV rays can cause damage to the deep structures of the eye, including the retina. Light focused on the macula (the most important part of the retina for vision) can cause damage in the area over time. Macular degeneration results in visual damage and even blindness.
Ok, so I hope I’ve convinced you that UV protection is critically important for your eyes… How can you protect yourself? There are 4 primary strategies:
1. Wear UV protective sunglasses. When buying sunglasses, check out their product labels and avoid glasses that are purely cosmetic – opt for those that block 99-100% of UV A and B rays. Larger glasses and wrap-arounds offer the most coverage. Remember that kids need sunglasses too!
2. Wear a wide-brimmed hat. Although a hat doesn’t always protect you from glare and light reflection from other surfaces, it can reduce the total amount of radiation that reaches your eyes and skin.
3. Wear UV-protective contact lenses. Most people don’t realize that some contact lenses are manufactured with a UV protective layer already built in. Although they are not large enough to protect the entire eye surface (or the skin around the eye) they offer an added layer of protection against harmful UV rays. However, not all contact lenses offer UV protection, and of those that do, not all provide similar absorption levels. An eye care professional can prescribe Class 1 UV-blocking contact lenses, which provide the greatest level of UV protection and which have a Seal of Acceptance for UV Absorbing Contact Lenses from both the American Optometric Association and the World Council of Optometry’s Commissions on Ophthalmic Standards. These lenses block more than 90 percent of UVA rays and 99 percent of UVB rays.
4. Protect your eyes all day. UV radiation for the eyes is actually worse when the sun is lower in the sky. Researchers at the Kanazawa Medical University in Japan found that during early morning and late afternoon, UV exposure to the eyes was about double that of the hours around noon during Spring, Summer and Fall.
For more information about protecting your eyes from the sun, you may enjoy listening to my recent interview with Dr. Stephen Cohen.* He is an optometrist who lives in Arizona – and is therefore well acquainted with UV radiation! Scroll down to the bottom of the page after clicking on the link and you’ll see the podcast.
***
Note that I was paid by Johnson & Johnson Vision Care, Inc. to host the radio show with Dr. Cohen.
June 16th, 2011 by RamonaBatesMD in Health Tips
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Yesterday, the U.S. Food and Drug Administration released the new rules regarding labeling of sunscreen. The goal is to make it easier for the average person to chose a sunscreen.
The new labels will not be in place until next summer, so you need to be aware.
When the new labels are in place, NO sunscreen will be allowed to be labeled as a SUNBLOCK or as WATERPROOF.
Under the new labeling rules
- Products that have SPF values between 2 and 14 may be labeled as Broad Spectrum if they pass the required test.
- Only products that are labeled both as Broad Spectrum with SPF values of 15 or higher may state that they reduce the risk of skin cancer and early skin aging, when used as directed.
- A warning statement will be required on any product that is not Broad Spectrum, or that is Broad Spectrum but has an SPF between 2 to 14 stating that the product has not been shown to help prevent skin cancer or early skin aging.
In addition to the final rule for sunscreen labeling, the FDA released a Proposed Rule which would Read more »
*This blog post was originally published at Suture for a Living*
