Health Consequences of recombinant bovine growth hormone (rBGH) use in dairy cattle

Recombinant bovine growth hormone (rBGH) is a genetically engineered drug developed by Monsanto, which is injected into dairy cows to increase milk production by a relatively small amount.

In a controversial decision, the FDA approved rBGH in 1993. Both Canada (1998) and the European Union (1999 and 2007) refused to approve rBGH, officially citing harm to cows' health. Their scientific committees cited concerns about rBGH's effects on human health. The Codex Alimentarius Commission, the UN's main food safety body, twice concluded there was no consensus that rBGH was safe for human health. The American Nurses Association, Consumers Union, Health Care Without Harm, Center for Food Safety, Food and Water Watch, Oregon Physicians for Social Responsibility, and others oppose rBGH use.

More than 90% of consumers favor labeling of rBGH-free products. Consumer awareness of the adverse consequences of rBGH has led to pressure on milk processors and retailers. Major companies (Starbucks, Kroger, Kraft, Wal-Mart, Tillamook, and others) have completely or partially disallowed it. However, federal school feeding programs (e.g., the National School Lunch Program) do not explicitly state that schools can request rBGH-free milk, creating a risk that milk from rBGH-treated cows may be funneled to U.S. schoolchildren as more retail outlets reject the product.

Problems with rBGH include:

1) rBGH increases the incidence of birth disorders, hoof problems, heat stress, diarrhea, and mastitis in cattle. The Humane Society, Animal Protection Institute, Humane Farming Association, and Farm Sanctuary, oppose rBGH.

2) Increased mastitis in rBGH-treated cows leads to increased use antibiotics commonly used to treat human infections, contributing to the development of antibiotic-resistant infections in humans.

3) rBGH use raises levels of insulin-like growth factor-1 (IGF-1) in cows. Casein, the main milk protein, allows most IGF-1 to survive pasteurization and digestion in humans, where considerable laboratory and epidemiological data suggest it may contribute to breast, colon, lung, and prostate cancers. Children, who consume more milk than adults, are disproportionately affected.

In absence of any benefit to consumers, the Precautionary Principle argues that rBGH should be removed from the market. Until then, schools should choose rBGH-free dairy products and labeling of rBGH-free dairy products should be protected.