Plantago, particularly Plantago ovata (psyllium), is widely recognized for its benefits to the large intestine (colon), with both traditional and scientific backing. The primary component, psyllium husk, is a soluble fiber commonly used as a bulk-forming laxative. Numerous clinical studies have shown that psyllium can relieve constipation and promote regular bowel movements by increasing stool bulk and water content, making it easier to pass. This effect supports overall colon health by promoting regularity and helping prevent conditions like hemorrhoids and diverticulosis.

In addition to constipation relief, some research suggests that Plantago may play a role in managing irritable bowel syndrome (IBS) symptoms and improving overall gut microbiota composition. The U.S. Food and Drug Administration (FDA) recognizes psyllium as effective for treating occasional constipation. Traditional medical systems, such as Ayurveda and traditional European herbalism, have also used Plantago seeds and husks for digestive support and colon cleansing for centuries.

While the majority of scientific evidence focuses on Plantago ovata (psyllium), other species like Plantago major and Plantago lanceolata have less direct evidence but are sometimes used traditionally for digestive support. Overall, the use of Plantago (especially psyllium husk) to support colon health is strongly supported by scientific research, particularly for increasing stool bulk and promoting regularity.