Psyllium husk is a type of dietary fiber that comes from the seeds of Plantago ovata, an herb commonly known as blond psyllium. It is primarily used as a laxative and to promote regular bowel movements due to its high mucilage content. The mucilage swells when it comes into contact with water, which helps to soften the stool and make it easier to pass. Psyllium husk can also be used for other purposes such as lowering cholesterol levels or managing blood sugar levels in people with diabetes.