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    How Might Obesity Affect Early Puberty?

    One possible explanation for the association between obesity and early puberty has to do with the hormone leptin, says Kaplowitz.

    Our fat cells make leptin. The more fat we have, the more leptin in our systems. Leptin seems to play a key role in regulating appetite, body type, and reproduction.

    Leptin doesn't trigger puberty on its own. But there's evidence that for puberty to start, a child has to have enough leptin in her system, Kaplowitz says. Girls who have high leptin levels -- because they are overweight -- could be more prone to early puberty.

    Biological changes in young babies could have a lasting effect, too. Studies have indicated that rapid weight gain during infancy might be related to later obesity and a higher risk of early puberty.

    There's another very different link. Obesity can cause some kids who don't actually have early puberty to get diagnosed with it anyway. Why? Sometimes, pediatricians mistake fat for breast development in girls.

    "That's not uncommon," Josefson tells WebMD. "It can be hard even for specialists like pediatric endocrinologists to distinguish between fat and breast tissue." Girls who are overweight might be at a higher risk of getting stuck with a wrong diagnosis.

    What Should Parents Do?

    What does the link between obesity and early puberty mean for your kids? Could preventing obesity lower the odds that your child will develop early puberty?

    That's theoretically possible, but experts aren't sure. Certainly, helping your kids keep a healthy weight is a good idea, since it has many health benefits. To help prevent excess weight gain in your child, you could:

    • Pay attention to the calories in your child's diet -- but without restricting food excessively.
    • Encourage regular physical activity.
    • Model healthy eating and exercise habits for your children.
    • Work closely with your child's pediatrician.

    What if your child has already started early puberty? In that case, weight loss may still be a good idea if your child is overweight, but it won't stop the process. "There's no evidence that losing weight will have any effect on a child who already has precocious puberty," says Kaplowitz.

    Puberty: What's Normal?

    When should puberty start? See the ages and changes to expect.
    View slideshow