On the side of your colon’s good guys — the good bacteria that resides there — is retired gastroenterologist Dr. Frank W. Jackson of Jackson GI Medical. As the maker of a supplement called Prebiotin, Jackson is gaining international prominence. And as the founder of Jackson Siegelbaum Gastroenterology, a Central Pennsylvania-based practice where he worked for 38 years before passing the baton to his son and partners, he wrote more than 1,000 pages of health content for a website that has attracted more than 7 million hits a year.

Since “retiring” five years ago, Jackson has expanded his patient load to a global audience, preaching nutrition and good digestive health to millions. He good-naturedly says he is a “notable failure at this retirement business.”

A graduate of Princeton University and Johns Hopkins Medical School, Jackson explained that while bad bacteria spawn sickness, good colonic bacteria bring health benefits such as strong bones, strengthened immunity, reduced constipation, greater appetite control and lower blood pressure.

With today’s genetic screening techniques, scientists can analyze the trillions of bugs and bacteria in the gut and work on fortifying the good ones. Enter Prebiotin, or oligofructose-enriched inulin (OEI), which is a plant-derived, full-spectrum prebiotic fiber. It nourishes good bacteria throughout the colon, moving through undigested and unchanged.