12/24/2007

7 Medical Myths That Might Have Your Doctor Duped

Medical myths abound. For Aaron Carroll, a pediatrician at the Regenstrief Institute in Indianapolis, the last straw was hearing an ominous radio report that warned parents that strangers might try to poison their kids on Halloween. "There hasn't been one documented case of a stranger actually doing that," Carroll says. (He adds that the few Halloween candy poisoning cases that have occurred have involved the child's family, not strangers.) The radio story prompted Carroll and a fellow pediatrician, Rachel Vreeman of the Indiana University School of Medicine, to start looking for other common, unsubstantiated beliefs. They found numerous examples and have just published a report in the British Medical Journal naming seven common medical misconceptions and laying out the evidence for why they're not true.

  1. We Use Only 10 Percent of Our Brain. People have been spouting this "fact" since 1907, but numerous brain-imaging studies have shown that no area of the brain is completely inactive.
  2. Drink at Least Eight Glasses of Water a Day. We've all heard that we're supposed to drink before we're thirsty and that our pee should be as clear as mineral water, but most of us get plenty of water from food and other drinks. Drinking water when you're thirsty makes sense, but eight glasses is setting the bar too high for many people.
  3. Hair and Fingernails Continue to Grow After Death. Makes for creepy fiction, yes, but actually it's the retraction of desiccating skin that makes the nails or hair of a cadaver appear to be growing. Real growth requires complex hormonal regulation, which stops at death.
  4. Shaving Hair Causes It to Grow Back Faster, Darker, and Coarser. No, no, and no. Newly sprouted hair looks dark because it has had minimal exposure to sun or chemicals, and it seems coarse because shaved hair lacks the finer taper seen at the ends of unshaven hair.
  5. Reading in Dim Light Ruins Your Eyesight. Dim light may force you to strain or squint your eyes, most ophthalmologists say, but it does not cause any eye damage.
  6. Eating Turkey Makes You Drowsy. Tryptophan, an amino acid that's linked to mood control and can cause drowsiness, is found in turkey meat. But chicken and ground beef contain similar amounts, and pork and Swiss cheese contain even more tryptophan per gram. Any large meal can induce sleepiness by decreasing blood flow to the brain.
  7. Mobile Phones Are Dangerous in Hospitals. Not one death caused by the use of a cellphone in a hospital has ever been reported, according to Carroll and Vreeman, though equipment malfunctions occasionally have been. Research actually suggests that allowing physicians to use cellphones inside hospitals reduces the risk of medical error and injury.

Source: health.usnews.com

12/20/2007

Sex Education Found to Help Teenagers Delay Sex

Teenagers who have had formal sex education are far more likely to put off having sex, contradicting earlier studies on the effectiveness of such programs, U.S. researchers said on Wednesday.

They found teenage boys who had sex education in school were 71 percent less likely to have intercourse before age 15, and teen girls who had sex education were 59 percent less likely to have sex before age 15.

Sex education also increased the likelihood that teen boys would use contraceptives the first time they had sex, according to the study by researchers at the U.S. Centers for Disease Control and Prevention, which was published in the Journal of Adolescent Health.

"Sex education seems to be working," Trisha Mueller, an epidemiologist with the CDC who led the study, said in a statement. "It seems to be especially effective for populations that are usually at high risk."

Mueller's team looked at a 2002 national survey of 2,019 teens aged 15 to 19.

They found teen boys who had sex education in school were nearly three times more likely to use birth control the first time they had intercourse. But sex education appeared to have no effect on whether teen girls used birth control, the researchers found.

Black teenage girls who had sex education in school were 91 percent less likely to have sex before age 15.

The researchers did not evaluate the content of sex education programs, including whether students were taught about contraception or about abstinence only.

Earlier studies, which relied on data from the 1970s through the 1990s, suggested sex education did little to persuade teens to delay sex.

The researchers said they think the difference may be that sex education in the United States is now more widespread and is being taught at earlier ages.

"Unlike many previous studies, our results suggest that sex education before first sex protects youth from engaging in sexual intercourse at an early age," they wrote.

Source: www.reuters.com

Study Says Green Tea May Cut Prostate Cancer Risk

Drinking green tea may reduce the risk of advanced prostate cancer, according to a study by researchers at Japan's National Cancer Center.

It said men who drank five or more cups a day might halve the risk of developing advanced prostate cancer compared with those who drank less than one cup a day.

"This does not mean that people who drink green tea are guaranteed to have reduced risk of advanced prostate cancer," said Norie Kurahashi, a scientist who took part in the study.

"We are just presenting our results. But the study does point to the hope that green tea reduces the risk of advanced prostate cancer."

Prostate cancer is much less common among Asian men than Western men, and that may be partly due to the effects of the high consumption of green tea in Asia, the study said.

But it said further studies are needed to confirm the preventive effects of green tea on prostate cancer, including well-designed clinical trials.

The study, published in the American Journal of Epidemiology, compiled data from 50,000 men aged 40-69 over a period of up to 14 years from 1990.

Cancer Research UK says on its Web site that a study of almost 20,000 Japanese men published in the British Journal of Cancer in 2006 found no relationship between green tea and prostate cancer.

Source: uk.reuters.com

12/18/2007

Severe Psoriasis May Up Risk of Death

Study Shows Patients With Severe Psoriasis Die Earlier

Psoriasis is not generally thought of as life-threatening, but it just might be for those with the severest forms of the disease.

People with severe psoriasis had a 50% increased risk of death compared with people without the inflammatory skin disease in a newly reported study.

Men with severe psoriasis died an average of 3.5 years earlier than men without the condition, while women with severe psoriasis died 4.4 years earlier than women without psoriasis.

Having mild psoriasis was not associated with an increased risk of death, and the researchers did not have information on causes of death.

But researcher Joel M. Gelfand, MD, says the findings make it clear that patients with severe psoriasis are at greater risk than has been realized.

"To put this in perspective, this finding suggests that more years of life are lost related to severe psoriasis than to severe hypertension," he tells WebMD.

Psoriasis and Death

As many as 7.5 million Americans have psoriasis, according to the National Institutes of Health.

About 80% to 85% of patients have mild to moderate psoriasis, while 15% to 20% have more extensive skin involvement. These patients generally require treatment with systemic medications like the drugs methotrexate and cyclosporine or newer biologics such as Enbrel, Remicade, and Humira.

Using a national medical records database from the U.K., Gelfand and colleagues from the University of Pennsylvania School of Medicine identified 133,568 patients with mild psoriasis, defined as having a diagnosis of psoriasis but no history of treatment for the condition.

An additional 3,951 patients were identified with severe psoriasis.

For each patient, up to five people without psoriasis who visited doctors for other causes were used for comparison.

During the study period, the death rate among patients with severe psoriasis was almost twice as high as in patients without psoriasis (21.3 deaths per 1,000 individuals per year vs. 12 deaths per 1,000 individuals per year).

During the study period, patients with severe psoriasis had a 50% increased risk of death compared with those without psoriasis. Those with milder psoriasis didn't have an increased risk of death compared to those without psoriasis.

The study appears in the December issue of the Archives of Dermatology.

Is Inflammation to Blame?

Earlier research by Gelfand and others found that people with severe psoriasis are at increased risk for a wide range of chronic conditions, including heart disease.

Psoriasis is now widely believed to be an autoimmune disease involving inflammation and the accelerated growth of skin cells and blood vessels, which produce the swollen, red lesions characteristic of the condition.

"One theory is that this chronic inflammation impacts other organs and systems within the body," Elizabeth Horn, PhD, of the International Psoriasis Council tells WebMD.

Inflammation within the body is increasingly recognized as a major contributor to a host of life-threatening conditions.

"We know that chronic inflammation is bad for a variety of organs and that it is probably involved in a number of chronic diseases, including cardiovascular disease and diabetes," Gelfand says.

Horn says the latest research should serve as a wake-up call to patients and their doctors that severe psoriasis is a serious disease.

"We are learning that there is something happening in people with severe psoriasis that may not be happening with milder forms of the disease," she says.

Horn and Gelfand agree that patients with severe psoriasis need to be especially vigilant about taking care of their overall health.

"It is very important for these patients to see their internist regularly, to have age-appropriate screenings, and to have their cardiovascular risks assessed and treated, if necessary," Gelfand says.

Source: www.webmd.com