The 5R Protocol was developed by the Institute for Functional Medicine as a way to, according to their website, "support and heal" the digestive tract and treat a "wide range of gastrointestinal symptoms and conditions." Practitioners claim that this process removes offending foods and pathogens, replaces digestive enzymes, reinoculates the gut with 'good' bacteria, and repairs the gut lining. But how much of this is based in microbiome science, and how much is simply science fiction?