Psyllium seed husks, also known as ispaghula, isabgol, or psyllium, are portions of the seeds of the plant Plantago ovata, (genus Plantago), a native of Bangladesh, India and Pakistan. They are hygroscopic, which allows them to expand and become mucilaginous.
Psyllium seed husks are indigestible and are a source of soluble dietary fiber. They are used to relieve constipation, irritable bowel syndrome, and diarrhea. They are also used as a regular dietary supplement to improve and maintain regular GI transit. The inert bulk of the husks helps provide a constant volume of solid material irrespective of other aspects of the diet or any disease condition of the gut. Some recent research has shown they may be effective in lowering cholesterol levels.