Which Fiber is Better: Metamucil or Citrucel?

December 16, 2025 •

2 min read

According to the National Institute of Diabetes and Digestive and Kidney Diseases, millions of adults experience chronic constipation, often turning to fiber supplements for relief. However, choosing between popular brands like Metamucil and Citrucel can be confusing, as each offers different benefits based on its primary fiber type.

Quick Summary

This guide compares Metamucil (psyllium husk) and Citrucel (methylcellulose) to help you decide which fiber supplement aligns best with your health goals. The comparison focuses on key differences like active ingredients, side effects, health benefits, and product forms.

Key Points

Fiber Type: Metamucil uses fermentable psyllium husk, while Citrucel uses non-fermentable methylcellulose, which causes less gas.
Gastrointestinal Comfort: Citrucel is typically recommended for individuals with sensitive stomachs or IBS because it is less likely to cause gas and bloating compared to Metamucil.
Additional Health Benefits: Metamucil's psyllium fiber has been shown to offer extra benefits like lowering cholesterol and helping manage blood sugar, which Citrucel's fiber does not.
Consistency and Mixability: Citrucel's powder dissolves more smoothly in liquid, whereas Metamucil's can be thicker and clumpier.
Constipation Relief: Both are effective bulk-forming laxatives that relieve occasional constipation within 12 to 72 hours.
Product Availability: Metamucil comes in a wider variety of forms, including powders, capsules, and gummies, while Citrucel is available in powders and caplets.

Comparing Metamucil and Citrucel: An In-Depth Look

Metamucil and Citrucel are both effective bulk-forming laxatives for treating occasional constipation and promoting regularity, but they differ in their fiber type and how they are processed in the gut, which affects user experience and additional health benefits. The best choice often depends on individual sensitivities and specific health goals.

The Fiber Source Difference: Psyllium vs. Methylcellulose

The main difference between Metamucil and Citrucel is their active ingredient. Metamucil uses psyllium husk fiber from the Plantago ovata plant. This is a fermentable soluble fiber that dissolves and ferments in the gut. Citrucel contains methylcellulose, a synthetic, non-fermentable fiber that passes through the digestive tract largely intact.

Gas and Bloating: A Major Deciding Factor

Due to fermentation in the gut, Metamucil is more likely to cause gas and bloating. Citrucel, being non-fermentable, is a gentler option often recommended for those with sensitive stomachs or IBS looking to avoid gas.

Additional Health Benefits

Beyond regularity, Metamucil's psyllium fiber can help lower cholesterol by binding to and removing bile acids and cholesterol, which supports heart health. It may also help manage blood sugar levels and promote fullness, aiding in appetite control. Citrucel does not offer these additional benefits.

Comparison Table: Metamucil vs. Citrucel


Feature	Metamucil (Psyllium Husk)	Citrucel (Methylcellulose)
Fiber Type	Fermentable soluble (mainly) and insoluble fiber	Non-fermentable soluble fiber
Source	Natural, from the Plantago ovata plant	Synthetic
Primary Function	Adds bulk, traps waste, absorbs water	Adds bulk, absorbs water
Side Effects (Gas)	More likely to cause gas and bloating	Less likely to cause gas and bloating
Heart Health Benefits	Can help lower cholesterol	Does not offer significant cholesterol-lowering benefits
Blood Sugar Support	Can help manage blood sugar levels	Limited effect on blood sugar levels
Constipation Relief	Effective, adds significant bulk to stool	Gentle, effective, adds bulk
Formulations	Powders, capsules, gummies, fiber thins	Powders, easy-to-swallow caplets
Mixability	Can be thicker and clumpier in liquid	Tends to dissolve more smoothly

Who is the Winner?

The best fiber supplement depends on your needs. Metamucil is better if you seek broader health benefits like lowering cholesterol or managing blood sugar. Citrucel is preferable for those sensitive to gas and bloating or with IBS due to its gentler, non-fermentable nature. Always consult a healthcare professional before starting new supplements, especially with existing medical conditions.

Conclusion

Metamucil and Citrucel are effective fiber supplements with distinct active ingredients leading to different outcomes. Metamucil offers additional heart health and blood sugar benefits but may cause more gas. Citrucel is a gentler option for those with digestive sensitivity. The best choice aligns with your body and health goals. Start with a low dose and increase gradually with plenty of fluids. More information on laxative differences can be found on sites like Drugs.com.

Frequently Asked Questions

Citrucel is generally considered the more gentle option. Its non-fermentable methylcellulose fiber is less likely to produce gas and bloating compared to the fermentable psyllium fiber found in Metamucil.

Yes, both Metamucil and Citrucel can be used daily to promote digestive health and regularity. However, it is always best to consult a healthcare provider for persistent issues or before using it long-term.

Both are effective bulk-forming laxatives for relieving occasional constipation, with relief typically occurring in 12 to 72 hours. The best choice depends more on your individual tolerance for side effects like gas and bloating.

Yes, Metamucil's psyllium husk fiber can provide additional health benefits, including helping to lower cholesterol and assisting with blood sugar management as part of a healthy diet.

Metamucil causes more gas because its psyllium husk is a fermentable fiber, meaning it is broken down by bacteria in the gut, which produces gas as a byproduct. Citrucel's methylcellulose fiber is non-fermentable.

It is generally not recommended to take multiple laxatives or fiber supplements simultaneously unless directed by a doctor. This could increase the risk of side effects like diarrhea and cramping.

The key difference is their mechanism. Metamucil's psyllium dissolves and forms a thick gel that traps and softens waste. Citrucel's methylcellulose passes mostly intact, adding bulk and water to stool.