250px|Hormones that control puberty. According to a new study, US girls are reaching puberty earlier than in the past 10-30 years. According to a new study, US girls are reaching puberty earlier than ever, a trend that raises some health concerns. The study, which was conducted in New York's East Harlem, the Cincinnati metropolitan area, and the San Francisco Bay area, showed that by age eight, 27\% of girls had begun puberty and showed breast development. By age seven, 15\% of girls were developing breasts. Though the study did not address why US girls were reaching breast development earlier, it found that heavier girls reached puberty earlier. Marcia Herman-Giddens of the University of North Carolina-Chapel Hill has said that the earlier puberty could be related to the rising obesity rate among US citizens. Currently, a third of US children are overweight or obese. Scientists and researchers are also worried about chemicals like bisphenol A (BPA) and atrazine that could disrupt growth hormones. The chemical industry says that these chemicals are safe and are harmless to humans. Herman-Giddens also said that it can be confusing to hit puberty at a young age. Girls reaching puberty at a younger age are more likely to attempt suicide. Also, earlier puberty can cause low self-esteem and depression and at adulthood, girls who reached puberty earlier are more likely to have breast cancer and endometrial cancer .
250px|Hormones that control puberty. According to a new study, US girls are reaching puberty earlier than in the past 10-30 years. According to a new study, US girls are reaching puberty earlier than ever, a trend that raises some health concerns. The study, which was conducted in New York's , the metropolitan area, and the area, showed that by age eight, 27\% of girls had begun puberty and showed breast development. By age seven, 15\% of girls were developing breasts. Though the study did not address why US girls were reaching breast development earlier, it found that heavier girls reached puberty earlier. Marcia Herman-Giddens of the has said that the earlier puberty could be related to the rising obesity rate among US citizens. Currently, a third of US children are overweight or obese. Scientists and researchers are also worried about chemicals like (BPA) and that could disrupt growth hormones. The chemical industry says that these chemicals are safe and are harmless to humans. Herman-Giddens also said that it can be confusing to hit puberty at a young age. Girls reaching puberty at a younger age are more likely to attempt suicide. Also, earlier puberty can cause low self-esteem and depression and at adulthood, girls who reached puberty earlier are more likely to have and .
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East Harlem, the Cincinnati
, the
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San Francisco Bay
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University of North Carolina-Chapel Hill
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bisphenol A
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atrazine
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breast cancer and endometrial cancer
and