Psyllium seed husks, also known as ispaghula, isabgol, or simply as psyllium, are portions of the seeds of the plant Plantago ovata, (genus Plantago), a native of India and Pakistan. They are soluble in water, expanding and becoming mucilaginous when wet.
Psyllium seed husks are indigestible in human beings and are often used as a source of dietary fiber. 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.
They are used to relieve constipation, irritable bowel syndrome, diverticular disease, and diarrhea. They are also used as a regular dietary supplement to improve and maintain regular GI transit.
Confusion with other spices
Psyllium seeds are very similar to the seed husks and can be used for many of the same purposes, although their use is less common.