RBGH stands for recombinant bovine growth hormone, an artificially produced version of the bovine somatotrophin (BST) hormone, which promotes growth and cell replication. rBGH increases milk production in cows by increasing the levels of insulin-like growth factor (IGF-1) circulating in the blood. All dairy products contain BST, because cows produce this naturally. rBGH, however, increases the cow's chances of developing mastitis, which requires antibiotic treatment.
United States Dairy Products
All dairy products that are not organic or specifically identified as rBGH-free may contain this synthetic hormone. This includes but is not limited to milk, cheese, yoghurt, ice cream and butter. Until recently, in fact, dairy distributors in certain states, such as Ohio, were not even allowed to identify whether their products were rBGH-free or not. Now, however, most dairy companies identify their rBGH-free status.
To determine which companies in your state use rBGH, look at a directory such as Sustainable Table's rBGH-free dairy map, which lists companies by state. Or, visit the Organic Consumers Association website for a list of companies that are partially or completely rBGH-free.
International Dairy Products
The European Union bans the use of all artificial hormones in food. Canada has shown concern about the increased instances of mastitis in cows and has banned rBGH. Kenya, Australia, New Zealand and Japan have also banned the use of rBGH. Therefore, dairy products in those areas are rBGH-free.
Humans also produce the BST hormone and IGF-1. Some organisations have shown concern that the artificial forms of these hormones could increase IGF-1 levels, possibly increasing the development of tumours, or expose people to antibiotic resistant bacteria.
The FDA reported in the 1980s and 1990s that consumption by humans of rBGH was safe and subsequently approved its use. Afterward, several organisations including Health Canada (the Canadian FDA) denounced the FDA's approval, stating their review was not extensive enough. Nevertheless, the National Institutes of Health, among others, have determined that rBGH is safe for human consumption.