What's the harm? "These girls have a greater risk of breast cancer and being overweight as adults," says Joyce Lee, M.D., a pediatric endocrinologist and lead author of the study. They're also more likely to drink and engage in sexual activity sooner. While genetics plays a role, establishing healthy eating and exercise habits now should help your daughter develop at a normal pace.
She may still be in Pull-Ups, but it's not too soon to start thinking about puberty. Girls who are overweight at age 3 or who pack on a lot of pounds between 3 and 7 have a much higher chance of developing earlier than their more fit peers, according to a study in Pediatrics. Researchers believe fat cells may secrete hormones that trigger puberty at ages 8 or 9 instead of the usual 10 or 11.