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TUESDAY, July 25 (HealthDay News) -- A new sunscreen just approved by the U.S. Food and Drug Administration promises protection for the full range of both ultraviolet A and B rays.

However, that doesn't mean people can disregard standard advice to avoid the sun and still protect their skin, experts stressed.

Anthelios SX, made by L'Oreal, is new in that it contains ecamsule (Mexoryl), an agent that shields skin from short-wave UVA rays -- something sunscreens currently available in the United States are unable to do. The product will be available to consumers this fall.

"There is nothing like this in the U.S.," said Dr. Darrell S. Rigel, a clinical professor of Dermatology at New York University and advisor to L'Oreal. "Basically, it lasts longer, and it gives better protection against UVA."

But a better sunscreen doesn't change the basic rules of skin protection.

"No sunscreen completely protects people against UVA radiation," said FDA spokeswoman Kimberly A. Rawlings. "This product and other sunscreens reducing UVA exposure should be used in conjunction with limiting time in the sun and wearing protective clothing. FDA has not compared this product with other sunscreens capable of reducing UVA exposure."

According to experts, UVB causes sunburn and skin cancer, while UVA causes aging and some skin cancers. Most sunscreens currently contain two active ingredients: avobenzone and octocrylene. Anthelios SX, which has an SPF of 15, contains those compounds as well, but adds in Mexoryl. Sunscreens containing Mexoryl have been available in Europe, Asia and Canada since 1993.

Why it has taken so long for the FDA to approve the product is not clear.

Rigel noted that most UVA protections are not chemically stable and breakdown quickly. "What Mexoryl does is stabilize them and make them last longer," he said.

While the retail price of Anthelios SX is not known, four-ounce sunscreens containing the same ingredients sell elsewhere for about $40.

One expert believes the best sun protection combines physical sun blocks with chemical ones.

"A lot of sunscreens break down in the sun. That's the dirty little secret that no one talks about," said Dr. Jeffrey C. Salomon, an assistant clinical professor of plastic surgery at Yale University School of Medicine. "In most sunscreens, there are both chemical and physical sun blocks."

Sun blocks such as zinc oxide and titanium physically block the sun from coming in, Salomon said. "Chemical sun blocks break down rapidly in the sun," he said. "You want a sunscreen that blocks both UVA and UVB, that has a high SPF, and that is waterproof."

"It's best to use a sunblock that contains both physical as well as chemical blockers," Salomon advised. Salomon recommends putting a shot-glass-size amount of sunblock on each arm and leg and on the chest and back. In addition, it should be put on at least 30 minutes before going into the sun and reapplied every two hours.

More information

For more on skin cancer, head to the U.S. National Cancer Institute.

MONDAY, July 24 (HealthDay News) -- Women who take the hormones estrogen and testosterone in tandem to treat symptoms of menopause appear to have an increased risk of breast cancer, researchers report.

The finding are published in the July 24 issue of the Archives of Internal Medicine.

Another report in the same journal issue finds that alternative therapies to hormone replacement therapy (HRT) don't seem to work.

In the first report, Rulla M. Tamimi, of Brigham and Women's Hospital in Boston and Harvard Medical School, and her colleagues collected data on 121,700 women, who were part of the Nurses' Health Study. The researchers looked at the long-term effects of estrogen-plus-testosterone therapy.

"Estrogen plus testosterone increases the risk of breast cancer," Tamimi said. "There needs to be other studies to support these findings, but there does seem to be an increased risk, and women and their physicians should weigh the risks and benefits of estrogen-plus-testosterone therapy before starting," she said.

There is some evidence that many of the symptoms of menopause --including decreased sex drive, mood swings and poorer quality of life, such as hot flashes, night sweats, vaginal dryness and sleep problems -- are related to this decline in testosterone, the authors noted. Previous clinical trials had shown that testosterone in combination with estrogen may reduce these symptoms and promote bone health.

The increased breast cancer risk associated with testosterone may be because enzymes in breast tissue convert testosterone to estradiol, an estrogen-like hormone that could contribute to the development of breast cancer, the authors said. Higher levels of testosterone alone have also been linked to increased breast-cancer risk in postmenopausal women.

Currently in the United States, there is only one estrogen-plus-testosterone therapy available, but such treatments are expected to increase in coming years, according to the report.

During 24 years of follow-up for the study, there were 4,610 cases of breast cancer. The 29 women who were taking estrogen plus testosterone had a 77 percent higher risk of developing breast cancer than those who never used hormone therapy, the researchers reported.

The risk associated with this combination therapy was higher than the risk associated with estrogen therapy (15 percent) and of estrogen-plus-progestin therapy (58 percent), Tamimi said.

Looking only at women who had gone through menopause naturally rather than those who had had a hysterectomy, Tamimi's group found that the 17 women who took estrogen plus testosterone had 2.5 times the risk of breast cancer compared with those who had never used hormones.

One expert doesn't think that, in most cases, testosterone should be prescribed for women.

"We have always been careful about prescribing testosterone to women, based on unknown risks," said Dr. Hugh Taylor, an associate professor of obstetrics and gynecology at Yale University School of Medicine. Testosterone doesn't appear to offer a benefit much beyond a placebo effect, he added.

"We have always been hesitant about using it, and this re-enforces it," Taylor said. "The usual reason women request testosterone is for decreased libido. But for most women, decreased libido is not due to decreased testosterone. It's due to a myriad of other problems."

Concerns about hormone-replacement therapy were first raised in 2002 by the Women's Health Initiative, the landmark study involving 27,000 participants that caused many women to discontinue their use of hormone therapy.

In the second study in the journal, researchers who reviewed 70 previous studies of alternative and complementary therapies for menopause-related symptoms found there was insufficient evidence that these therapies relieve menopause-related symptoms.

"There is a significant placebo effect in almost anything that is used for the management of menopause," said study lead researcher Dr. Anne Nedrow, of the Oregon Evidence-based Practice Center and Oregon Health and Science University. "There is a lack of any evidence that of the millions and millions of dollars spent on alternative therapies that anything really works.

Nedrow's group looked at 48 studies that examined vitamins, proteins, complete diets or other biologically based treatments; nine studies that focused on mind-body therapies, including meditation and guided imagery; one study of osteopathic manipulation, a body-based therapy; two that looked at the energy-based treatments reflexology and magnet therapy; and 10 that assessed whole medical systems, such as traditional Chinese medicine or ayurvedic medicine, a traditional therapy from India.

Nedrow said the study found there really aren't any good alternative or complementary choices for women going through menopause. "The truly symptomatic women may need to reconsider estrogen," she said. "Or we may want to take advantage of the placebo effect, which has shown a 50 percent reduction in symptoms in 12 weeks," she added.

Nedrow said she doesn't think there's any harm in using alternative therapies. She recommended black cohosh or soy supplements, with the understanding that most of the effect would be a placebo effect.

One expert agreed that the benefit of alternative therapy to relieve menopausal symptoms is largely a placebo effect.

"Currently, the best medication we have to remove menopausal symptoms is estrogen," said Dr. Jennifer Wu, an obstetrician/gynecologist at Lenox Hill Hospital, in New York City. But, she added, "The associated risks make it less than desirable."

More information

For more on menopause, visit the National Library of Medicine.

THURSDAY, July 20 (HealthDay News) -- A new study pinpoints the key role of a specific growth factor in keeping eyes healthy. The finding might even aid cancer research, researchers say.

U.S. researchers say large amounts of the protein VEGFR-3 (vascular endothelial growth factor receptor-3) on the top epithelial layer of the cornea keeps the cornea transparent and free of blood vessels and, thus, makes vision possible.

The cornea is the thin, clear tissue that covers the front of the eye. It's one of the few tissues that actively keeps itself free of blood vessels. Until now, researchers did not know exactly how the cornea managed to do this.

VEGFR-3 inhibits blood vessel growth in the cornea by binding or neutralizing growth factors that would normally stimulate blood vessel growth, said scientists at the Schepens Eye Research Institute and Massachusetts Eye and Ear Infirmary.

Their finding was published in this week's online issue of the Proceedings of the National Academy of Sciences, and is expected to be published in the July 25 print issue.

The study answers a scientific mystery and may also eventually help researchers find ways to prevent and cure blinding eye diseases and also illnesses such as cancer, where blood vessels grow abnormally and uncontrollably.

"Drugs designed to manipulate the levels of this protein could heal corneas that have undergone severe trauma or help shrink tumors fed by rapidly growing abnormal blood vessels. In fact, the next step in our work is exactly this," study senior author Dr. Reza Dana, senior scientist at Schepens and head of the Cornea Institute at the Massachusetts Eye and Ear Infirmary, said in a prepared statement.

More information

The U.S. National Eye Institute has more about the cornea and corneal disease.

WEDNESDAY, July 19 (HealthDay News) -- Eli Lilly & Co.'s popular cancer drug Gemzar has received U.S. Food and Drug Administration approval to be used as a treatment for recurrent ovarian cancer, the company said.

This new approval covers the use of Gemzar in combination with carboplatin to treat women who've suffered an ovarian cancer relapse at least six months after treatment, the Associated Press reported.

Ovarian cancer recurs in 90 percent of women who are diagnosed and treated, according to Lilly. There will be an estimated 20,180 new cases of ovarian cancer in the United States this year, the American Cancer Society says.

Gemzar already had FDA approval to treat breast cancer, lung cancer, and pancreatic cancer, the AP reported.

More information

To learn about ovarian cancer, visit the U.S. National Cancer Institute.