Psyllium is a soluble fiber that is primarily used as a bulk-forming laxative.

The soluble fiber found in psyllium husks helps to softens stool, as well as and relieve constipation, irritable bowel syndrome, hemorrhoids, and other intestinal problems.

When psyllium husk comes in contact with water, it swells and forms a gelatinous mass that stimulates the transport of waste through the intestinal tract.

Unlike wheat bran and some other fiber supplements, psyllium generally does not cause excessive gas and bloating. Make sure you drink at least 8-8 ounce glasses of water per day when taking psyllium. For those intoleant so psyllium, see acacia fiber.  

Constipation
Many studies have found that psyllium relieves constipation. Psyllium helps to speed the passage of stool through the digestive tract. It does this by softening the stool and attracting water thereby producing more bulk, which stimulates the transit of waste through the gastrointestinal tract.

Diarrhea
Psyllium can be used as a bulk-forming agent to help relieve mild to moderate diarrhea. Psyllium soaks up a significant amount of water in the digestive tract, thereby making stool firmer and, under these circumstances, slower to pass.

Irritable Bowel Syndrome (IBS)
Several well-designed studies have found that soluble fiber (including psyllium) helps regulate stool frequency and consistency in people with IBS. Psyllium also has the additional advantages over other sources of fiber of reducing flatulence and bloating.

Hemorrhoids
Psyllium may be recommended by a physician to help soften stool and reduce the pain associated with hemorrhoids.

Inflammatory Bowel Disease (IBD)
In a study of people with ulcerative colitis (a type of inflammatory bowel disorder), psyllium seeds were as effective as the prescription drug mesalamine in decreasing recurrences of the disease. In addition, a physician may recommend the use of psyllium as a bulking agent for mild to moderate cases of diarrhea from either ulcerative colitis or Crohn's disease (another type of inflammatory bowel disorder).

High Cholesterol
Soluble fibers such as those in psyllium husk, guar gum, and oat bran have a cholesterol-lowering effect when added to a low-fat, low-cholesterol diet. Studies have shown psyllium to be quite effective in lowering total as well as LDL ("bad") cholesterol levels, which can be helpful to those with high cholesterol (hypercholesterolemia) and those at increased risk for developing hypercholesterolemia, such as people with type 2 diabetes.

Diabetes
Studies suggest that a high-fiber diet, which may include psyllium, an lower insulin and blood sugar levels and improve cholesterol and triglyceride levels in people with diabetes.

Obesity
Studies and clinical reports suggest that psyllium may enhance the sensation of fullness and reduce hunger cravings. For these reasons, incorporating psyllium and other sources of fiber into the diet may aid weight loss.

High Blood Pressure
Although the studies are not entirely conclusive, the addition of fiber (namely, 12 grams of soluble fiber per day), particularly psyllium, may help lower blood pressure.

Heart Disease
Incorporating high-fiber foods (such as psyllium-enriched cereals) into the diet may help lower heart disease risk.

Cancer
A diet high in fiber may help to guard against the development certain types of cancer such as prostate, breast, colon and lining of the uterus.

References

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