We have all met children who are considered “physically advanced” for their age. Research now suggests that girls who are unusually large as young children, are more likely to undergo puberty at an early age, and are also significantly more likely to be obese during adulthood. The term used to describe this type of early development is “constitutional advancement of growth” or CAG.
Researchers in Greece publishing in the October 2010 issue of Journal of Clinical Endocrinology and Metabolism, 95:4535 reviewed the world literature and found that between 50 and 70% of obese children develop into obese adults. Obese girls are also much more likely to have precocious or early puberty. Most endocrinologists define precocious puberty in girls as breast development beginning by the age of 7 years. Therefore, the combination of rapid growth as a young child (ages 2 to 4 years) predisposes girls to have early puberty and proceed on to obesity as an adult. Similar associations of rapid childhood development and adult obesity has not been seen in boys.
Although researchers can only speculate about the connection of accelerated early childhood growth and the later development of obesity, a prominent theory is that insulin resistance in the womb and as an infant may set the stage for the onset of CAG in early childhood and adult obesity.
Gary Pepper, M.D., Editor-in-Chief, Metabolism.com