Metamucil is a common over-the-counter dietary supplement often used to prevent or relieve occasional constipation 1. It is also used in some instances as part of a weight loss program. While Metamucil is safe when used as directed, as with any medication, improper use can lead to other medical issues.


Metamucil is easy to take. It comes in a variety of forms, including powder, tablets, and wafers. The powder comes in a variety of flavors, including orange, pink lemonade and berry, and is mixed with water by the user. The Metamucil products are also relatively inexpensive.

Health Benefits

Metamucil contains 100 percent natural fiber which is helpful in relieving occasional constipation 1. According to it also helps lower cholesterol, which can limit the risk of developing heart disease.

Weight Loss

Some dieters claim that Metamucil is effective as a weight loss supplement 1. According to, Metamucil is just as effective as more expensive weight loss supplements like FiberThin and ZetaCap. The product may help to curb appetite when taken just before a meal.

Lack of Evidence

Despite some of the claims, there is no concrete evidence showing that Metamucil reduces body fat or is effective for weight loss over the long haul. There is also no proof that it will result in any changes to how the body metabolizes food.

Vitamin Deficiency

Some people who take Metamucil for weight loss may be tempted to take excess amounts in an effort to speed the process. Taking more than the recommended dosage can ultimately result in a vitamin deficiency. Diarrhea could also result, leading to dehydration.

Dependency and Side Effects

People who abuse Metamucil or any other laxative may become psychologically dependent on the product. Side effects may occur, including abdominal bloating. In rare cases, severe side effects may be present, such as an allergic reaction, such as a rash, tightness in the chest, difficulty swallowing or vomiting.