Wednesday, January 28, 2009

Babies Know - A Little Dirt Is Good for You -

Ask mothers why babies are constantly picking things up from the floor or ground and putting them in their mouths, and chances are they'll say that it's instinctive — that that's how babies explore the world. But why the mouth, when sight, hearing, touch and even scent are far better at identifying things?

When my young sons were exploring the streets of Brooklyn, I couldn't help but wonder how good crushed rock or dried dog droppings could taste when delicious mashed potatoes were routinely rejected.

Since all instinctive behaviors have an evolutionary advantage or they would not have been retained for millions of years, chances are that this one too has helped us survive as a species. And, indeed, accumulating evidence strongly suggests that eating dirt is good for you.

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Tuesday, January 27, 2009

Which came first, the belly or the stress?

Stress. How many images can a single word conjure? With an economy in the tank, jobs on the line and personal finances in peril, to say these are stressful times is an understatement. Yet, when it comes to your weight, we tend not to think of stress as a factor, unless it leads to obvious changes in behaviour, such as skipping meals because of a tight schedule or bingeing on a tub of ice cream after a bad day. But beneath the surface, the physiological effects of stress tend to be much more subtle -- and to have consequences that extend much deeper than the choices you make at the table.

Last week, I wrote about the impact of long-term sleep deprivation on body weight; this week, we'll look at the underappreciated role that stress plays on weight and overall health.

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Monday, January 26, 2009

Premarital Abstinence Pledges Ineffective, Study Finds - Washington Post

Teenagers who pledge to remain virgins until marriage are just as likely to have premarital sex as those who do not promise abstinence and are significantly less likely to use condoms and other forms of birth control when they do, according to a study released today.

The new analysis of data from a large federal survey found that more than half of youths became sexually active before marriage regardless of whether they had taken a "virginity pledge," but that the percentage who took precautions against pregnancy or sexually transmitted diseases was 10 points lower for pledgers than for non-pledgers.

"Taking a pledge doesn't seem to make any difference at all in any sexual behavior," said Janet E. Rosenbaum of the Johns Hopkins Bloomberg School of Public Health, whose report appears in the January issue of the journal Pediatrics. "But it does seem to make a difference in condom use and other forms of birth control that is quite striking."

The study is the latest in a series that have raised questions about programs that focus on encouraging abstinence until marriage, including those that specifically ask students to publicly declare their intention to remain virgins. The new analysis, however, goes beyond earlier analyses by focusing on teens who had similar values about sex and other issues before they took a virginity pledge.

"Previous studies would compare a mixture of apples and oranges," Rosenbaum said. "I tried to pull out the apples and compare only the apples to other apples."

The findings are reigniting the debate about the effectiveness of abstinence-focused sexual education just as Congress and the new Obama administration are about to reconsider the more than $176 million in annual funding for such programs.

"This study again raises the issue of why the federal government is continuing to invest in abstinence-only programs," said Sarah Brown of the National Campaign to Prevent Teen and Unplanned Pregnancy. "What have we gained if we only encourage young people to delay sex until they are older, but then when they do become sexually active -- and most do well before marriage -- they don't protect themselves or their partners?"

James Wagoner of the advocacy group Advocates for Youth agreed: "The Democratic Congress needs to get its head out of the sand and get real about sex education in America."

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The Evidence Gap - Genetic Tests Offer Promise of Personalized Medicine

For more than two years, Jody Uslan had been taking the drug tamoxifen in hopes of preventing a recurrence of breast cancer. Then a new test suggested that because of her genetic makeup, the drug was not doing her any good.

“I was devastated,” said Ms. Uslan, 52, who stopped taking tamoxifen and is now evaluating alternative treatments. “You find out you’ve been taking this medication for all of this time, and find out you are not getting benefit.”

Ms. Uslan’s situation is all too common — and not just among the hundreds of thousands of women in this country taking tamoxifen.

Experts say that most drugs, whatever the disease, work for only about half the people who take them. Not only is much of the nation’s approximately $300 billion annual drug spending wasted, but countless patients are being exposed unnecessarily to side effects.

No wonder so much hope is riding on the promise of “personalized medicine,” in which genetic screening and other tests give doctors more evidence for tailoring treatments to patients, potentially improving care and saving money.

Many policy experts are calling for more studies to compare the effectiveness of different treatments. One drawback is that such studies tend to be “one size fits all,” with the winning treatment recommended for everybody. Personalized medicine would go beyond that by determining which drug is best for which patient, rather than continuing to treat everyone the same in hopes of benefiting the fortunate few.

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