HGH human growth hormone has been around for a long time now. When they first started using the HGH they were using pituitary glands from cadavers (which are a dead bodies) . There were a lot of these people that had Creutzfeldt-Jakob disease which is a lot like mad cow disease. They don't want people to get the CJD so now they make sure they only use the synthetic human growth hormone. They stopped using HGH from cadavers in the early 1980's. researches have found they haven't found anyone with the CJD after taken HGH since 1977. Let's hope this was the end of the HGH nightmare.