Study: 7 Becoming the New Age to Hit Puberty in Some U.S. Cities - AOL Health
A factor they forgot (?) to mention: birth-control drugs in the water supply. There's a lot of that going around any more, as well. In summary: Uh-oh . . .
http://www.aolhealth.com/2010/08/09/study-7-becoming-the-new-age-to-hit-puberty-in-some-u-s-cities/?icid=main|htmlws-main-n|dl3|link4|http%3A%2F%2Fwww.aolhealth.com%2F2010%2F08%2F09%2Fstudy-7-becoming-the-new-age-to-hit-puberty-in-some-u-s-cities%2F
American girls are reaching puberty at increasingly younger ages, with more experiencing it as early as 7, new findings suggest.
The most dramatic changes in early-onset puberty were found in white girls, in whom the rates have nearly doubled in the past 13 years.
The study, published online Monday in the journal Pediatrics, builds on ground-breaking research from 1997 that first reported girls were hitting puberty as young as age 7.
A team led by Dr. Frank Biro, a pediatrician at Cincinnati Children's Hospital Medical Center, found that about 23 percent of black girls and 10 percent of white girls began puberty by age 7.
In 1997, the rate of 7-year-old girls hitting puberty was about 5 percent for whites and 15 percent for blacks.
By age 8, 43 percent of black girls had reached puberty compared with 18 percent of whites, according to the current research. The rates for 8-year-old black girls were about the same in 1997 but significantly lower for whites, when only 11 percent of 8-year-olds entered puberty.
About 15 percent of Hispanic girls had begun puberty by age 7 and about 31 percent by age 8.
Breast development was used to detect the onset of puberty. Girls who develop earlier may be more likely to get breast cancer and engage in risky behavior like sex than girls who go through puberty later. They also are more prone to depression.
"For the 11-year old that looks like she's 15 or 16, adults are going to interact with her like she's 15 or 16, but so are her peers," Biro told Reuters Health. "It doesn't mean that they're psychologically or socially more mature."
He and his fellow researchers at the University of Cincinnati School of Medicine looked at 1,239 girls aged 7 and 8 in New York, San Francisco and Cincinnati and found that they were more likely to develop at a younger age than the girls from across the U.S. in the 1997 study.
Both teams found significant discrepancies in puberty start ages across different races, with the current study seeing the biggest shifts downward among white girls.
The increase in younger girls hitting puberty could be a factor of the rising obesity rates, doctors believe. Biro and his colleagues learned that those with a higher body mass index at ages 7 and 8 were much more likely to be developed than girls of that age who were slimmer.
"We think that one of the more important contributing factors is the higher body mass index in the girls in the 21st century," Biro told MedPage Today.
A study released in June found that girls with diets high in meat and junk food were at risk of early puberty. In that study, scientists from Brighton University learned that 7-year-old girls who ate meat 12 times a week were 14 percent more likely to reach puberty by the age of 12 than those who ate meat four or fewer times a week.
The latest research subjects aren't necessarily indicative of the trends for all girls in the U.S., the authors say. They're still tracking the girls in the study in the hopes of expanding on their findings to date.
http://www.aolhealth.com/2010/08/09/study-7-becoming-the-new-age-to-hit-puberty-in-some-u-s-cities/?icid=main|htmlws-main-n|dl3|link4|http%3A%2F%2Fwww.aolhealth.com%2F2010%2F08%2F09%2Fstudy-7-becoming-the-new-age-to-hit-puberty-in-some-u-s-cities%2F
American girls are reaching puberty at increasingly younger ages, with more experiencing it as early as 7, new findings suggest.
The most dramatic changes in early-onset puberty were found in white girls, in whom the rates have nearly doubled in the past 13 years.
The study, published online Monday in the journal Pediatrics, builds on ground-breaking research from 1997 that first reported girls were hitting puberty as young as age 7.
A team led by Dr. Frank Biro, a pediatrician at Cincinnati Children's Hospital Medical Center, found that about 23 percent of black girls and 10 percent of white girls began puberty by age 7.
In 1997, the rate of 7-year-old girls hitting puberty was about 5 percent for whites and 15 percent for blacks.
By age 8, 43 percent of black girls had reached puberty compared with 18 percent of whites, according to the current research. The rates for 8-year-old black girls were about the same in 1997 but significantly lower for whites, when only 11 percent of 8-year-olds entered puberty.
About 15 percent of Hispanic girls had begun puberty by age 7 and about 31 percent by age 8.
Breast development was used to detect the onset of puberty. Girls who develop earlier may be more likely to get breast cancer and engage in risky behavior like sex than girls who go through puberty later. They also are more prone to depression.
"For the 11-year old that looks like she's 15 or 16, adults are going to interact with her like she's 15 or 16, but so are her peers," Biro told Reuters Health. "It doesn't mean that they're psychologically or socially more mature."
He and his fellow researchers at the University of Cincinnati School of Medicine looked at 1,239 girls aged 7 and 8 in New York, San Francisco and Cincinnati and found that they were more likely to develop at a younger age than the girls from across the U.S. in the 1997 study.
Both teams found significant discrepancies in puberty start ages across different races, with the current study seeing the biggest shifts downward among white girls.
The increase in younger girls hitting puberty could be a factor of the rising obesity rates, doctors believe. Biro and his colleagues learned that those with a higher body mass index at ages 7 and 8 were much more likely to be developed than girls of that age who were slimmer.
"We think that one of the more important contributing factors is the higher body mass index in the girls in the 21st century," Biro told MedPage Today.
A study released in June found that girls with diets high in meat and junk food were at risk of early puberty. In that study, scientists from Brighton University learned that 7-year-old girls who ate meat 12 times a week were 14 percent more likely to reach puberty by the age of 12 than those who ate meat four or fewer times a week.
The latest research subjects aren't necessarily indicative of the trends for all girls in the U.S., the authors say. They're still tracking the girls in the study in the hopes of expanding on their findings to date.