Almost all conventionally raised cattle in the U.S. and Canada are given hormones, in the form of anabolic steroids, in order to encourage faster growth, a practice that has been going on since 1956. This practice is used by the beef and dairy industry in order to increase profits. On average, for beef it adds about 40 to 50 extra pounds to the weight of a steer at the time of slaughter, for a greater profit of approximately $25. Artificial hormones are also commonly used in milk production, where recombinant Bovine Growth Hormone (rGBH) or recombinant bovine somatotrophin (rBST) is used to increase milk production in cows by 10 to 15 percent.
However, this practice is banned in several countries, including all countries in the European Union, due to the potential risk to human health in those who eat meat or drink milk from hormone-treated animals. Several studies point to the disturbing effects these hormones have on the human endocrine system, including links to the early onset of puberty in girls, lower sperm quality in males and increased risk of cancer.
Despite the FDA’s claims that the level of hormones used in the production of beef and milk do not adversely affect human health, there is evidence to suggest otherwise. The FDA claim of safety is based on a single study conducted by Monsanto (the corporation that produced the hormone) in which rGBH was tested on 90 rats for 30 days with no apparent problems.
Interestingly, this study was never published or formally peer-reviewed. In the late 1990s, scientists working for Health Canada (the Canadian government’s equivalent of the FDA) sparked controversy when they investigated both the complete Monsanto study and the way its findings were applied by the FDA in its approval process. They found that, while the underlying data in no way proved that rGBH poses a hazard to human health, the data should have raised enough concern to trigger a full human health review prior to the FDA giving approval for the hormone’s use.
After an animal is slaughtered, measurable levels of hormones can be found in the muscle, fat and organ meats, such as the liver and kidneys. One example of the significant impact on those who eat meat and drink milk from conventionally raised animals on a regular basis can be seen in a 2007 study comparing the sperm quality of men whose mothers consumed beef during pregnancy. Mothers with high beef consumption during pregnancy (more than 7 meals per week) had adult sons who were three times more likely to have sperm concentrations in the sub-fertility range than the mothers who were in the low beef consumption group (fewer than 7 beef meals per week).
Another issue gaining greater prominence is the increasingly early onset of puberty in girls. The average age of first menstruation in 1900 was 14. Today that age is 12 ½. Hormone residues in meat and milk, such as estrogen, are thought to be the culprits. And the longer that estrogen exists in the body, and the higher the levels, the greater the risk of breast cancer.
It has also been shown that the hormones consumed in meat products stimulate the production of insulin-like growth factor (IGF) in the body, which increases the risk of prostate cancer by 50 percent and premenopausal breast cancer by 65 percent, not to mention causing an increased risk of other cancers.
If you enjoy eating meat and dairy, the simplest way to avoid consuming these harmful hormones is to buy organic products. Organic meat and milk comes from animals that have not been treated with hormones or antibiotics, allowing you to enjoy your meal without worrying about hormone dangers.