In 1993 the FDA approved the commercial sale of milk from rbGH treated cows. Despite this approval, there are a number of public health concerns that have arisen about the safety of this milk. Specifically, there is concern that this milk may increase the risk and rate of cancer. Milk from rbGH treated cows has elevated levels of IGF-1. Furthermore, some amount of IGF-1 from the milk is orally active in humans. IGF-1 has a strong association with a number of cancers including breast, prostate and colorectal cancer. For these reasons, the safety of milk from rbGH treated cows seems very questionable.