Tuesday, July 13, 2010

Can Your Sunscreen Cause Skin Cancer?

A dermatologist sheds light on a new study that claims your SPF might be doing more harm than good.

A new study has found that an overwhelming amount of sunscreens on the market contain an ingredient that speeds cancerous cell growth. That's right: sunscreen might cause cancer, the very thing people lather it on to protect themselves from.

But don't go throwing out your white creams, sprays, oils, and lotions just yet. Many doctors and dermatologists aren't convinced that sunscreen should go the way of canola oil and old-school Coppertone.

Dr. Marta Rendon, a board-certified dermatologist and global spokesperson for Procter & Gamble's Head and Shoulders division, tries to assure worried consumers that the results — released last week by the Environmental Working Group, a nonprofit public health organization — come from animal testing only and are the findings of "just one study."

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 to Rendon, who acknowledges that some studies suggest "that vitamin A might have some phototoxicity." Still, she says that "it does not necessarily correlate that it'll increase your risk of skin cancer."

To be safe, however, Rendon recommends using sunscreen that blocks both UVA rays — the ones that penetrate the skin more deeply to cause aging issues such as fine lines and wrinkles — and UVB rays, which are the ones that can give you a sunburn and are more responsible for cancer.

"Both forms of ultraviolet light are carcinogenic and increase the risks of skin cancer, but some sunscreens don't target both — most of the new ones are UVA blockers," Rendon says. "You need to block both."

Although in its annual report, the EWG only recommended 39 of the 500 products they examined as safe to use, Rendon says that all FDA-approved sunscreens have undergone rigorous trials to prove their efficacy and hold up against safety standards. (Some brands she recommends? Any with Helioplex, such as Neutrogena's line, or with Mexoryl like La Roche-Posay.)

But regardless of where you stand, she says that by following a few simple rules, you'll be safe in the sun:

Check the product label. Make sure your sunscreen includes zinc oxide or titanium dioxide, which act as physical barriers and keep ultraviolet light out best.

Don't worry about SPF. Sun protection factor is not regulated by the FDA, and as it turns out, sunscreens with a high SPF — like 70, 80, or 100+ — really don't work any better than those half its count. "The difference between SPF 30 and SPF 60 is maybe five percent," Rendon says. "Those with lighter complexion, freckles, or red hair should use SPF 45 to 50 with good UVA and UVB blockage. For normal complexions, SPF 30 is just fine."

Don't under-do it. "A shot glass is the right amount, and reapply every two hours," she says, adding that you can't really ever put on too much.

Remember that sunscreen isn't the only armor against sun damage. "You have to be conscious of sun exposure," Rendon warns. "Wear hats and sun-protective clothing."

Look for European brands. "It's true that Europe has better sunscreens because they process ingredients faster than we do," she admits.

Source: http://health.msn.com/health-topics/skin-and-hair/articlepage.aspx?cp-documentid=100260739>1=31036

Saturday, July 3, 2010

Age at Menopause May Predict Cardiovascular Risk

Researchers at the University of Alabama say that asking a woman at what age she went through menopause may be a good tool to predict her future risk of cardiovascular disease. The results of the study were presented the annual meeting of The Endocrine Society, on June 19, 2010 in San Diego, CA.

The researchers found that women who reported early menopause were twice as likely as others to have any kind of heart disease.


Approximately 2,500 women who were part of the Multi-Ethnic Study for Atherosclerosis were followed in the current study. All women had gone through menopause naturally or surgically (for example, by having their ovaries removed). Early menopause was defined as occurring before the age of 46, and 693 of the study’s participants fell into this category. More women undergoing early menopause were African-American or Hispanic than other ethnicities, and more women who’d reported early menopause went through it because of surgery.

The researchers found that women who reported early menopause were twice as likely as others to have any kind of heart disease, which included “heart attack, resuscitated cardiac arrest, definite angina, probable angina (if followed by revascularization), stroke, stroke death, coronary heart disease death or other atherosclerotic/CVD death," said lead researcher Melissa Wellons in a University news release.

Wellons did point out that it’s important to remember that this study was correlational in nature, so it does not provide concrete evidence of cause and effect. Still, the age of onset of menopause could be an effective marker to help predict a woman’s likelihood of having a cardiovascular event down the road. She says that the findings “will give clinicians a new tool potentially to assess cardiovascular risk... the simple tool of asking when a woman had a hysterectomy or their ovaries removed or when they went through natural menopause.”

The ethnic differences found in the study may also be important for doctors to keep in mind: "Because black and Hispanic women reported more incidence of early menopause, these findings may be particularly helpful and relevant to them," said Wellons. "However, more research still is needed to better understand the underlying mechanisms behind early menopause and cardiovascular disease."

Source: http://www.thedoctorwillseeyounow.com/content/womens_health/art2979.html