Hordenine is a natural compound found in certain plants, including barley and beer. However, Hordenine impurities can be present in the form of other alkaloids that may have negative effects on the body. The presence of impurities can affect the purity and quality of Hordenine supplements, which are commonly marketed as weight loss aids and pre-workout supplements. It is important to ensure that Hordenine supplements are free of impurities to ensure their safety and efficacy.