The premise of body cleansing is based on the Ancient Egyptian and Greek idea of autointoxication, in which foods consumed or in the humoral theory of health that the four humours themselves can putrefy and produce toxins that harm the body. Biochemistry and microbiology appeared to support the theory in the 19th century, but by the early twentieth century, detoxification based approaches quickly fell out of favour. Despite abandonment by mainstream medicine, the idea has persisted in the popular imagination and amongst alternative medicine practitioners. In recent years, notions of body cleansing have undergone something of a resurgence, along with many other alternative medical approaches. Nonetheless, mainstream medicine continues to view the field as unscientific and anachronistic.
Skip juice cleanses or liquid diets. A popular cleansing regimen for losing weight involves drinking only juice or another type of liquid for a few days to a week. This is dangerous because you could end up without essential nutrients. These extreme cleanses are also counterproductive because most people just gain back any weight they lost when they go back to eating normal food again. Doctors don't recommend any sort of diet like this, and say following a healthy diet and exercise routine is much better for losing weight.