Effects of obesity on growth and puberty.

Nutrition is an important regulator of the tempo of human growth. Infancy may represent a critical "window" where variations in nutrition have longer-term consequences for growth and development. Rapid weight gain during infancy is associated with accelerated growth and early pubertal development. Rapid weight gain in infancy is also associated with the development of insulin resistance and an exaggerated adrenarche. Such circulating hormonal changes, together with elevated leptin levels and integral effects of fat cells on hormone action through local 11beta-steroid dehydrogenase and aromatase activity could effect rate of progression of pubertal development in obese subjects. The secular trends in growth and maturation are partly attributed to changing nutrition. Recent data suggest that age at menarche may be static, but there is a debate as to whether the first signs of puberty are being seen much earlier in obese girls. Rapid early weight gain, obesity and early development may have implications for later health through the development of PCOS and overall association with cancer risk.