I have done some Liver Flushes and also colonics and coffee enemas. My opinion is that they can be helpful but it is important to understand that these things are complementary to the main shift that must be made. That shift is cleaning your internal terrain and alkalizing the body by eating a diet high in living foods.
There is no quick fix - nothing in a bottle or in the form of a seven day cleanse. The good news is that you can feel the gradual improvements so there is a lot of positive reinforcement when you fully commit to these changes.
If you read texts by Arnold Ehret (i.e. the Mucusless Diet System) you will understand that our modern way of eating leaves quite a bit of residue inside the body. This becomes the culturing medium (food source) that parasites/microbes live on and it also becomes a source of fermentation and putrefaction (a.k.a. the Body Odor ).
When we start eating astringent fruits like grapes, Watermelon and citrus as well as drinking lemon water and herbal teas we can begin to move the lymphatic system and dissolve this mucus residue. I did this while using anti-parasitic herbs and it has helped greatly. I am not done though. Once you have a parasite problem it can be challenging to manage it so don't give up hope. It takes a long time to fully cleanse and regenerate the body but I believe it is possible.