Having been down that road a time or two I don’t currently do, believe in , or advocate that sort of cleansing as it can be pretty harsh on the body systems (while the intention is well meaning). There are certain times where there are radical issues in the body and that might warrant radical responses however that’s on a case-by-case basis (not generally).
The body, by design, is self-celansing. However that requires two specific behaviors from us; the proper combination of whole foods and personal responsibility for our lives. For example, a person that chooses immobility and blames it on something else (like not having enough time) that person may develop difficulty with the innate processing of toxins. The lymphatic system relies on movement as it does not have its own pump and so a sedentary life can inhibit that system’s function.
Since we often choose instant gratification - a fast meal, fast pain relief, fast resolution to our deepest problems, fast opening of our hamstrings - it is challenging then to make change and address that which we are putting into our system, that which we are breathing, that which we are drinking. So instead we don’t make change there. No. Instead we continue tossing garbage in and resorting to fasts in order to placate our self-guilt and indulgences. This shared from my personal experiences, those of my teachers, and the observation of my students.
Instead I prefer taking in those things which deeply nourish the systems which handle cleansing rather than taking in something that cleanses. One is regeneration and the other is substitution.