Homeopathy
Homeopathy became popular because it was created at a time when medicine did not work very well and could make people sick. Back then, taking homeopathy might have kept people from getting hurt by bad doctors. However, medicine has improved since then, and now helps a lot more than it hurts people. Some homeopaths have told their patients not to take medicines like antibiotics and vaccines that could cure (or keep them from getting) dangerous diseases. Hence the use of homeopathy, instead of obtaining real medical help, can cause unnecessary suffering, disease and/or death.