Benefiber vs Citrucel: Which Fiber Supplement Is Better? (2026)

Benefiber and Citrucel are the two main alternatives people turn to when Metamucil's gritty texture and gas production drive them away. Both are gentler, both cause fewer side effects, but they achieve this through different fiber types with different trade-offs.

How Do Benefiber and Citrucel Work Differently?

Benefiber (wheat dextrin) is a soluble fiber that dissolves completely in liquid. It absorbs water in your intestines, adding gentle bulk to stool. Wheat dextrin is partially fermentable — gut bacteria can break down some of it, producing mild gas, but significantly less than psyllium.

Citrucel (methylcellulose) is a semi-synthetic fiber derived from plant cellulose. Unlike most fibers, methylcellulose is non-fermentable — gut bacteria cannot break it down at all. This means it passes through your system adding bulk and absorbing water without producing any gas. It's the gentlest fiber supplement available.

Which Causes Fewer Side Effects?

Citrucel wins on gas reduction — it's the only fiber supplement that produces virtually zero gas because methylcellulose doesn't ferment. For IBS patients, people with severe bloating, or anyone who finds that even Benefiber causes uncomfortable gas, Citrucel is the logical choice.

Benefiber wins on texture and taste. It dissolves completely in any liquid with no thickening, no grit, and no detectable taste. Citrucel dissolves well but creates a slightly thicker consistency, particularly in cold liquids.

Both cause minimal bloating compared to Metamucil. Neither causes cramping or urgency.

Which Is More Effective for Constipation?

Clinical evidence suggests both are moderately effective for constipation prevention, though neither has the extensive evidence base that psyllium (Metamucil) does. Both add bulk and improve stool consistency when taken daily with adequate water.

The main limitation of both products: they're preventive tools, not rescue tools. If you're already constipated, adding fiber can temporarily worsen symptoms. Start either product before constipation develops, or combine with an osmotic laxative (MiraLAX) for active treatment.

When Should You Choose Each One?

Choose Benefiber if invisible convenience is your priority — you want to add fiber to your morning coffee without anyone (including you) noticing. It's ideal for people who want the easiest possible daily fiber habit.

Choose Citrucel if minimal gas is your priority — you have IBS, severe bloating sensitivity, or you've tried other fiber supplements and the gas was unbearable. Citrucel is the gentlest option in the entire fiber category.