evidence: The terrain theory, which can be traced back to French chemist Antoine Béchamp, has been used as a competing explanation with germ theory for why diseases occur. The terrain theory argues that diseases aren’t caused by germs, but by imbalances in the host organism resulting from lifestyle, such as nutritional deficiencies. As such, correcting the imbalance will cure the disease. [...] Health Feedback previously addressed a similar claim about terrain theory, explaining that the existence of microzymes has never been demonstrated and that viral infection demonstrably produces changes even in healthy cells that are consistent with disease. [...] However, the fact that some principles of the terrain theory explain why certain diseases occur doesn’t mean that germ theory is wrong. Diseases can result from infectious and non-infectious causes. Our understanding of diseases and how to treat them draws on the principles of both theories. The denial of germ theory espoused in the Instagram reel lends users an incorrect understanding of how diseases occur and can be potentially dangerous if it leads them to reject proven treatments and preventative measures.