Metamucil and psyllium husk can help treat constipation. They may also decrease appetite, but using them for weight loss may not be safe or effective.

Metamucil is a supplement that’s often used to treat constipation and support regularity.

It’s also sometimes used for weight management due to its ability to decrease appetite and promote feelings of fullness.

However, Metamucil has also been associated with several adverse effects, leading many to wonder whether it’s safe and effective for weight loss.

This article reviews whether Metamucil can help you lose weight, as well as whether you should use it for that purpose.

Spoonful of MetamucilShare on Pinterest
SmartStock/Getty Images

Metamucil is a fiber supplement made from psyllium husk, a compound derived from the seeds of Plantago ovata, also known as blond plantain (1).

It’s a type of soluble fiber, which means that it absorbs water and forms a gel-like consistency as it passes through your digestive tract (2).

Metamucil is often used to support digestive health, lower cholesterol levels, reduce appetite, and improve blood sugar control.

It also helps promote regularity by trapping water in the intestines, easing the passage of stool from the body (1).

It’s available in powder, capsule, and wafer form and can be purchased over the counter without a prescription.


Metamucil is a soluble fiber supplement made from psyllium. It’s commonly used to support digestive health, decrease cholesterol, reduce appetite, and improve blood sugar levels.

Several studies have focused on the potential weight loss effects of Metamucil and psyllium.

For instance, one study in 51 people with type 2 diabetes found that supplementing with psyllium decreased constipation, blood sugar levels, and body weight, compared with a control group (3).

Another study observed similar findings, noting that psyllium improved blood sugar control and decreased body mass index (BMI) in 40 people with type 2 diabetes (4).

Studies also show that psyllium may help reduce appetite and increase feelings of fullness, which may be especially beneficial for weight loss.

In fact, one review showed that supplementing with soluble fiber — and psyllium fiber, in particular — may help keep you feeling fuller for longer between meals (5).

Similarly, another small study found that taking Metamucil before breakfast and lunch for 3 days led to reductions in hunger and the desire to eat, as well as increased fullness between meals (6).

However, despite these potential benefits, Metamucil or similar fiber supplements shouldn’t be used as a weight loss product.

Instead, try to increase your intake of soluble fiber through foods like fruits, vegetables, and legumes. These foods can help you increase your fiber intake to support weight loss, and they supply important vitamins, minerals, and antioxidants to improve your overall health.


Studies suggest that taking Metamucil may help reduce hunger, enhance feelings of fullness, and increase weight loss. Still, Metamucil and similar fiber supplements should not be used as a weight loss product.

Although studies show that Metamucil may be beneficial for weight loss, there are a few side effects to consider.

In particular, it may cause mild digestive issues for some people, including gas, bloating, or belching (6, 7).

Be sure to start with a low dosage and increase your intake gradually to help minimize unpleasant side effects.

It’s also important to ensure that you’re drinking enough water when taking Metamucil, as it has been shown to cause severe side effects, such as bowel obstruction, when taken without adequate fluids (8).

If you have diabetes or a history of gastrointestinal disorders like Crohn’s disease or ulcerative colitis, you should talk with your healthcare provider before using fiber supplements like Metamucil.

You should also consult your healthcare provider if you’re taking any other medications, as Metamucil can interfere with the absorption of certain types of drugs (9).


Metamucil may cause mild digestive issues for some people and can interfere with certain medications. Be sure to drink plenty of water and increase your dosage slowly to prevent side effects.

Increasing your intake of fiber using a soluble fiber supplement like Metamucil may help reduce hunger and appetite to promote weight loss.

However, it can also interfere with certain medications and may cause digestive issues for some people, including bloating, belching, and gas.

Due to these risks, you should only take Metamucil after consulting your healthcare provider.

Moreover, despite some of their potential benefits for weight loss, Metamucil and similar fiber supplements should not be used as weight loss products.

A better approach would be to try and eat more soluble-fiber-rich foods, such as fruits, vegetables, and legumes.

These foods can not only increase your intake of fiber to support weight loss but also supply a variety of important vitamins, minerals, and antioxidants to support overall health.