https://www.mountsinai.org/health-library/supplement/psyllium

Psyllium is a soluble fiber used primarily as a gentle bulk-forming laxative in products such as Metamucil. It comes from a shrub-like herb called Plantago ovata that grows worldwide but is most common in India. Each plant can produce up to 15,000 tiny, gel-coated seeds, from which psyllium husk is derived.

The soluble fiber found in psyllium husks can help lower cholesterol. Psyllium can help relieve both constipation and diarrhea, and is used to treat irritable bowel syndrome, hemorrhoids, and other intestinal problems. Psyllium has also been used to help regulate blood sugar levels in people with diabetes. When psyllium husk comes in contact with water, it swells and forms a gelatin-like-mass that helps transport waste through the intestinal tract. Several large population based studies also suggest that increased fiber intake may reduce risk of colon cancer, but other studies have been conflicting.

Colon Cancer

After some promising early studies, newer results examining whether a high fiber diet protects against colon cancer have been mixed. Most large, well-designed studies have found only a slight association between fiber intake and colorectal cancer risk. In addition, fiber does not appear to protect against the recurrence of colorectal cancer.

Constipation

Many well-designed studies have shown that psyllium relieves constipation. When combined with water, it swells and produces more bulk, which stimulates the intestines to contract and helps speed the passage of stool through the digestive tract. Psyllium is widely used as a laxative in Asia, Europe, and North America.

Diabetes

Studies suggest that a high-fiber diet may help lower insulin and blood sugar levels and improve cholesterol levels in people with diabetes. It may also reduce the chance of developing diabetes in those who are at risk.

Diarrhea

Psyllium can also be used to help relieve mild-to-moderate diarrhea. It soaks up a significant amount of water in the digestive tract, making stool firmer and slower to pass.

Heart Disease

Adding high fiber foods (such as psyllium-enriched cereals) to your diet may help lower heart disease risk. In fact, studies show that a diet high in water-soluble fiber is associated with lower triglyceride levels, and a lower risk of cardiovascular disease.

Hemorrhoids

Your doctor may recommend psyllium to help soften stool and reduce the pain associated with hemorrhoids.

High Blood Pressure

Although studies are not entirely conclusive, adding fiber to your diet, particularly psyllium, may help lower blood pressure. In one study, 6 months of supplementation with psyllium fiber significantly reduced both systolic and diastolic blood pressure in overweight people with hypertension.

High Cholesterol

Soluble fibers, such as those in psyllium husk, guar gum, flax seed, and oat bran, can help lower cholesterol when added to a low-fat, low-cholesterol diet. Studies have shown psyllium can lower total, as well as LDL (bad) cholesterol levels, which may help reduce the risk of heart disease. In combination with cholesterol-lowering drugs, such as statins, psyllium provides an added benefit to reducing cholesterol levels.

Inflammatory Bowel Disease (IBD)

Although studies suggest conflicting results, some physicians recommend psyllium for mild-to-moderate cases of diarrhea from either ulcerative colitis or Crohn disease (another type of inflammatory bowel disorder). In one study of people with ulcerative colitis, psyllium was as effective as the prescription drug mesalamine (Pentasa, Rowasa, Asacol) in maintaining remission. However, for some people with IBD, too much psyllium can make symptoms worse. Work closely with your doctor to decide how much fiber is right for you.

Irritable Bowel Syndrome (IBS)

Several studies have found that soluble fiber (including psyllium) helps relieve some symptoms of IBS, such as diarrhea and constipation. Other studies, however, have found mixed results.

Obesity

Studies and clinical reports suggest that psyllium may make you feel fuller and reduce hunger cravings.