University of Minnesota Medical School researchers analyzed data from a national survey of more than 20,000 students in grades 7 through 12 during three separate years, reports EurekAlert. In the survey's first year, nearly 15 percent of the teens said they thought they had a 50/50 chance of living to age 35. Those who were already fighting, using drugs, having unsafe sex, or who had attempted suicide were more likely to say in later interviews that they'd die young. The reverse was also true: Teens who hadn't engaged in such behaviors but said they would die young in the first interview were more likely to have started by the second and third interviews.

"While conventional wisdom says that teens engage in risky behaviors because they feel invulnerable to harm, this study suggests that in some cases, teens take risks because they overestimate their vulnerability, specifically their risk of dying," said Dr. Iris Borowsky, who worked on the study. "These youth may take risks because they feel hopeless and figure that not much is at stake."

Twenty-five percent of the survey participants living in households that receive public assistance said they would die young. Race was also a factor in their responses, as only 10 percent of Caucasian teens said they'd die young, but 29 percent of American-Indian, 26 percent of African-American, 21 percent of Hispanic, and 15 percent of Asian respondents said they thought they might not see 35.

There was no link between the students thinking they'd die young and the number who did die over the course of six years of research, but the more fatalistic teens were significantly more likely to have been diagnosed with HIV/AIDS by the end of the study.

Dr. Jonathan Klein, a University of Rochester adolescent health expert who did not work on the report, says the study suggests doctors should be screening teens to find out if they believe they may die early. "Asking about this sense of fatalism is probably a pretty important component of one of the ways we can figure out who those kids at greater risk are," he explains.

Teens Who Believe They'll Die Young Are More Likely To Engage In Risky Behavior, University Of Minnesota Research Finds [EurekAlert]
Surprising Number Of Teens Think They'll Die Young [Associated Press]

In a study published in the journal Nature Cell Biology, Chinese researchers performed experiments on mice, showing for the first time that a mammal can produce new eggs as an adult that lead to healthy offspring, reports theWashington Post. Scientists from Shanghai Jiao Tong University identified female germ line stem cells in ovaries removed from mice. After coaxing the cells to multiply, they were injected into sterile mice. Some of the cells matured into eggs, and another group of mice was able to produce healthy offspring.

While men produce new sperm daily, for at least 50 years scientists have believed that female mammals are born with all the eggs they will ever have and the supply is depleted over time, leaving them infertile after menopause. The new study raises new possibilities for the treatment of infertility, as freezing stem cells may be more efficient than freezing eggs and there may be ways to stimulate the cells to produce eggs in older women. The cells may also have a use in stem cell research by producing embryonic stem cell lines specific to individual patients.

Several recent studies have suggested that women may generate more eggs during adulthood, but this is the first time scientists have obtained the cells that can produce healthy new eggs from a mammal. "If you are looking to disprove that females cannot make new eggs, this paper proves it. It's a really significant paper," said Harvard Medical School professor Jonathan L. Tilly, who published some of the earlier research. "This is the smoking gun."

Other scientists say more research needs to be done on humans, not mice, and question if the mice used in the experiment were really completely sterilized. "The aging process of the human egg differs fundamentally from that of the mouse egg," said David L. Keefe, a professor of obstetrics and gynecology at the University of South Florida. "Except at Disney World, humans are not large mice."

Still, doctors hope that the cells could lead to new procedures someday, especially since treating infertility has become a lucrative, multibillion dollar business. The L.A. Times reports that the competition became so intense at the Huntington Reproductive Center in Pasadena, one of the biggest fertility practices on the West coast, that it has spurred a series of lawsuits. After founder Dr. Joel Batzofin's business grew to make a $5 million yearly profit, his five partners took a secret vote and ousted him from the business. The former partners sued each other in a six year legal battle that led to private detectives posing as patients. A female detective submitted to an ultrasound of her uterus and ovaries, and one of the doctors gave his own sperm sample to a rival doctor, pretending to be a patient, all in an effort to show that Batzofin was violating a non-compete agreement at his new practice. "It's a cutthroat business," said Batzofin. "There is a lot of greed."

But according to another new study published this week, even more women may be turning to fertility treatments, as having a high-powered career has supposedly been linked to lowered fertility. The Times of London reports that University of Utah anthropologist Elizabeth Cashdan found that women with stressful careers experience a hormonal shift that replaces estrogen with male androgens that are associated with strength, stamina, and competitiveness.

Cashdan analyzed the waist to hip ratio (WHR) of women from 37 different populations and cultures, and found the average WHR to be above 0.8. She says that due to a hormonal shift, the women had a more straight-up-and-down figure that is less conducive to child-bearing. Previous studies have found that women with an hourglass figure, with a WHR of 0.7 are the most fertile.

"Although the hormonal profile associated with a high WHR may favour success in some stressful and difficult circumstances where women must work hard, there are well-known costs," said Cashdan. "Women may suffer lower fertility and possibly lower attractiveness to men who may have an innate preference for curviness."

A Possible Step Toward Setting The Biological Clock [The Washington Post]
Fertility Doctors' Competition Spawns Lawsuits [The L.A. Times]
Is Your Career Making You Infertile? [The Times of London]

Three new studies published this week in The New England Journal of Medicine confirm that adults have stores of adipose tissue that burns energy, rather than storing it like better-known "white" fat, reports Time. Scientists have known for years that rodents and newborns have large deposits of the fat, which contains a high concentration of dark-colored mitochondria. The tissue burns sugar and releases the energy as heat, which allows mice and babies to shiver to keep warm in cold temperatures.

As humans develop the ability to regulate their body temperature, they lose the brown fat cells, which are mostly present in a sheet on a baby's back. Now scientists have found that adults actually retain large stores of brown fat in deposits around the neck. Scientists studying cancer patients have known for years that there are spots on the neck that burn a large amount of glucose, but they didn't know what they were looking at. Usually, that indicates a growing tumor, but biopsies would show the spots were not cancerous.

"It is, in a sense, the discovery of a new organ," said Sven Enerback, lead author of one of studies, reports The Washington Post. People with the most active brown fat are cancer patients and people with hyperthyroidism. Women, thinner people, and younger people, also had more brown fat than men or people who are older and fatter. The studies showed that brown fat is activated by cold. Subjects left in an ice bath or a 61 degree room for two hours showed more brown fat activity than those in warm conditions because their bodies were trying to generate heat. The New York Times reports that the fat can also be triggered by catecholamines, hormones that regulate part of the fight or flight response.

Currently the drugs that stimulate those hormones have too many side effects, but doctors hope that in the future a drug that will safely trigger brown fat will be developed. However at this point, scientists are not sure that brown fat will necessarily lead to burning white fat, since the body tries to maintain equilibrium and may alter other metabolic systems to try to make up for the loss.

[Image via Flickr.]

Study: A Fat That Helps You Lose Weight? [Time]
Studies Find A Way Adult Bodies May Fight Obesity [The Washington Post]
Brown Fat Identified As Heat-Yeilding Cells In Humans [The New York Times]

Researchers at Northern Illinois University measured the levels of the stress hormone cortisol during an S&M party and found that stress levels rose for the receiver during the scene, but returned to normal within 40 minutes. At another S&M event, researchers found that testosterone levels rose only in receiving women, which may happen to help women cope with the stress of the event. The couples reported increased relationship closeness afterwards and scientists say their findings show consensual sex is not stressful overall, even when it is extreme. But, if you're looking to get closer to your partner without breaking out the riding crop, psychologist Richard Wiseman says any shared activity will do the trick. "It doesn't have to be tying up your partner or placing clamps on their nipples, it could be something as simple as cooking a meal together or even doing the housework as a duo," he says. [The New Scientist]

A new study by psychologists at Hertfordshire University in Britain found that women are more likely to go on a shopping spree 10 days before their periods begin, reports the BBC. Professor Karen Pine conducted a study of 443 women from the ages of 18 to 50 and asked them about their spending habits. Of the 153 women in the study who were in the later stage of their menstrual cycle, almost two thirds said they had recently bought something on impulse and 57% said they overspent by more than £25. "The later women were in their menstrual cycle, the more likely they were to have overspent," said Pine. "Spending was less controlled, more impulsive and more excessive for women in the luteal phase."

The psychologists had two theories as to why the women were spending more right before they got their periods. They believe women may be shopping excessively in an attempt to deal with negative emotions they experience during their cycle. These hormonal fluctuations affect the part of the brain that deals with emotions and inhibition. "The spending behavior tends to be a reaction to intense emotions. They are feeling stressed or depressed and are more likely to go shopping to cheer themselves up and using it to regulate their emotions," Pine said, according to The Daily Mail.

Since previous research has found that women dress up more while they are ovulating, Pine's other theory is that women are buying things during this time to make themselves feel more attractive. Most of the items the women reported spending too much on were jewelry, makeup, and high heels.

The research also showed that women had more buyer's remorse right before they get their period. Pine suggests, "If women are worried about their spending behavior then they should avoid going shopping at the end of their menstrual cycle." Uh, thanks.

Shopping Sprees Linked To Periods [BBC]
How A Woman's 'Time Of The Month' Can Be Blamed For Her Desire To Go Shopping [The Daily Mail]

Researchers from the Universite Laval in Quebec had 14 students relax while sitting, read and summarize a passage, and perform tests on a computer, then offered them as much food as they wanted. Even though the intellectual tasks only required 3 more calories than relaxing, the students ate more than 200 calories after summarizing the text and performing the tests. Researchers say the overeating may have been motivated by stress, or because the subjects were trying to restore glucose, which the brain uses for fuel. "Caloric overcompensation following intellectual work, combined with the fact that we are less physically active when doing intellectual tasks, could contribute to the obesity epidemic currently observed in industrialized countries," said lead researcher Jean-Philippe Chaput. [UPI]

One quarter of women who wear a size 14 (equivalent to a U.S. size 12) said they were extremely happy with their lives, more than any other dress size, according to a study by Special K. Women who are a U.K. size 24 are the least happy, but the survey found that happiness did not correlate to size, as the fourth least happy size was a 6. Though 12, 14, and 16, were among the happiest sizes, of the 3,000 women surveyed, 48 percent still said they were not happy with their weight. [The Telegraph]

As the Washington Post reports, a new study conducted by Janet E. Rosenbaum of the John Hopkins Bloomberg School of Public Health found that teens who take "virginity pledges" are not less likely to engage in premarital sex than their non-pledging peers.

The study compared teens who take "virginity pledges" — who tend to come from families that are more religious and conservative and less sex positive — with teens who did not take a pledge but who come from similar backgrounds. In the past, studies of abstinence programs compared religious and conservative teens with more liberal and sex positive teens, which Rosenbaum says is like comparing "apples to oranges." By comparing pledgers with peers who come from a similar backgrounds, Rosenbaum was able to test how effective the "virginity pledge" was in reaching its desired audience... and discovered that the pledge was ineffective: by 2001 she found that 82 percent of those who took the pledge had retracted their promises and there was no significant difference in sexual activity from their peers. In fact more than half of both of the groups studied engaged in fairly typical sexual behavior: they had engaged in different types of sexual activity, had an average of three partners and had sex before they were 21, even if they were unmarried.

The most disturbing part of the study was that it found that teens who took the pledge were less likely to use protection when they eventually did have sex. (This morning on the Today show, Meredith Vieira discussed the study with psychotherapist Laura Berman.)

Ultimately, the study suggests that abstinence programs are ineffective since, as Rosenbaum notes, abstinence is more of an "individual conviction rather than participating in a program." Unfortunately, abstinence programs like "virginity pledges" can create poor sexual practices by not educating teens about different forms of contraception, yet our government spends more than $176 million annually on funding similar, abstinence-focused programs. As Dr. Berman said to Vieria, this is exciting news for the sex education-positive incoming Obama administration.

Study: Teenage 'Virginity Pledges' Are Ineffective [Washington Post, via MSNBC]

Researchers from the University of Barcelona measured the alertness levels of 668 university students throughout the day after drinking a cup of espresso coffee. The caffeine improved the activity levels of both genders, but had a greater impact on the men. Researchers also found that even a cup of decaffeinated espresso coffee caused a slight improvement in their subjects' alertness, but the effects of decaf coffee were more noticeable among the women. [Science Daily]

Image via Flickr.

The study, published in the Journal of Applied Psychology, found that men who said they believe in more traditional gender roles earned $11,930 more per year than men with more modern views. Women who held more traditional views made an average of $1,500 less than women with more equal views. Researchers came to this conclusion after analyzing data collected by a Labor Department survey that has tracked the changing attitudes of 12,000 people since 1979. Participants were polled four times from their late teens on and asked questions such as whether they believe a woman' place is in the home, or whether the employment of women is likely to lead to higher rates of juvenile delinquency.

Critics of the gender-gap theory usually say that the difference between what men and women earn is due to men choosing higher paying professions in law or business while more women go into education or social work...or men working longer hours. But researchers say their conclusions in this study were based on men and women with similar jobs, education, and hours per week.

Though the study was designed to prove a link between gender attitudes and pay, not to explain why or how those attitudes come about, researchers have suggested two possible explanations: Men with traditional beliefs may negotiate harder for pay raises, and/or employers may discriminate against employees who see gender roles more equally. The good news is that if this study is correct that the wage gap is partly a result of attitudes about gender roles, as more Americans adopt more progressive attitudes about women in the workplace, the differences in income may disappear.

Study: Traditional Men Earn the Most [MSNBC]
Men With Sexist Views Earn More [BBC]