Is colon cleansing necessary? What is its purpose? Colon cleansing has been believed to remove toxins from our gastrointestinal tract that may cause a variety of health problems. Although some critics say it’s generally unnecessary and at times may even be harmful. They believe that the digestive system and bowel naturally eliminate waste material and bacteria, thus our body does not need special diets or pills to do this. But if you believe on the advantages of colon cleansing, take the time to read several colon cleansing review out there. It may help you choose the best product for you.