A recent study of American boys shows that they are starting to develop sexually a full six months to two years earlier than their fathers did.
Young teenage boys who have to start shaving before they even enter high school should not feel they are unusual or the only one who needs to break out the razor in middle school as a new study published in the journal Pediatrics shows that boys in the United States are starting puberty earlier than ever these days.
The study’s lead author Marcia Herman-Giddens from the University of North Carolina's School of Public Health and her colleagues’ found that boys are starting to sexually develop six months to two years earlier than medical textbooks have indicated as the average standard.
The onset of puberty is more difficult to identify for boys than girls as the girl’s breast development and the start of menstrual cycles are easy to identify, but for the boys the onset of puberty only shows up in the form of enlarged testes and the production of sperm. To conduct their study, the authors asked 212 medical practitioners across the country to examine 4,100 boys aged 6 to 16 and record the data on the boys' genital size and pubic hair appearance. The researchers then assigned each boy's data to one of five stages of puberty and then compared the ages and puberty stages of all the boys, reporting only the observable physical changes and not internal hormonal levels. The results showed that the African-American boys start hitting puberty at about 9 years old, while the non-Hispanic white and Hispanic boys began developing at around 10 years old.
The researchers do not suggest that the observed numbers should be treated as a new standard for pediatricians because they suspect our environment may be playing a role in accelerating puberty. Dr. Herman-Giddes said "The changes are too fast, as genetics take maybe hundreds, thousands of years. You have to look at something in the environment. That would include everything from a lack of exercise to junk food to TV to chemicals."
Prior studies have linked chemicals in the environment to everything from decreases in sperm concentration to increases in birth defects and behavioral problems in children, but determining the exact chemicals among the food additives, pesticides and other chemicals that may be causing the hormonal changes has been difficult. The researchers worry that because puberty represents a physiological change in the brain, early onset may also have the effect of shortening childhood for many young boys today. Some studies have shown that early development in girls has been linked to poor self-esteem, eating disorders, and depression, but fewer studies have been aimed at boys and the findings have not been as clear.
Although the most recent study by Dr. Herman-Giddes does appear to show that American boys are starting puberty earlier than they have in the past, the study also indicates they are not reaching full sexual maturity any faster than they have in the past. Even though many boys may have to start shaving earlier than their fathers did, they will still reach full sexual maturation at about the same time as boys in this country always have.
