Next Page: Sex hormones and early puberty [ pagebreak ] Sex hormones and early puberty
IGF isn't the only hormone found in the food supply. Ranchers have been fattening up cattle with sex hormonesmost notably estrogensince the 1950s. Today most beef cows in the .except those labeled "organic"receive an implant in their ear that delivers a hormone, usually a form of estrogen (estradiol) in some combination with five other hormones. (These hormones are not given to chicken and pigs because they don't have the same growth-promoting effect in these animals, although antibiotics are given to all three species for similar growth-promoting reasons.)
For boys with severe gynecomastia that is causing substantial tenderness or embarrassment, a short course of a drug called tamoxifen (sample brand name: Nolvadex) or raloxifene (brand name: Evista) may be recommended. These drugs block the effects of estrogen in the body and can reduce the size of the breasts somewhat. However, neither of these drugs is approved in the United States for the treatment of gynecomastia. Drugs may be prescribed without US Food and Drug Administration (FDA) approval, although the risks and benefits have not been studied completely.