Stool form and regularity
Benefiber Daily Prebiotic Fiber Supplement Powder
A taste-free, single-ingredient wheat dextrin powder — a soluble fiber with a notably weaker constipation record than psyllium.
What Benefiber is: a single-ingredient powder of wheat dextrin, a soluble fiber that dissolves clear, does not thicken and has no taste. What the reviews say: it carries about 13,100 Amazon ratings, and the recurring complaint is new gas after what reviewers call a reformulation, though the label still lists wheat dextrin as the only ingredient. Does Benefiber work for constipation? Wheat dextrin is non-viscous, so it does not form the water-holding gel psyllium does; the meta-analysis of 16 fiber trials found significant effects for psyllium and pectin, not wheat dextrin, and one evidence review describes wheat dextrin as mildly constipating at typical doses. Its evidence-backed role is as a gentle, well-tolerated fiber source rather than a constipation treatment. The reviews, the trials and the label follow below.
- Format
- Powder, once a day
- Type
- Fiber
- Cost
- $0.18 a day
- Customer rating
- 4.7 out of 5 from 13,096 ratings from Amazon
What customers consistently report
- Dissolving clear with no taste or grit
- Not causing bloating for many users
- Being recommended by gastroenterologists per some reviewers
Those are the themes that recur across the reviews. High review confidence — 13,096 Amazon ratings.
Why it might work
Wheat dextrin is a soluble prebiotic fiber that dissolves clearly into drinks, so it can raise daily fiber intake without grit, flavor, or a thick texture. It is non-viscous, however: unlike psyllium, it does not form a water-holding gel, so it does not offer the same stool-bulking mechanism for constipation. That distinction matters more than the shared word soluble. Benefiber's advantage is simplicity and tolerability rather than a strong laxative-style effect: wheat dextrin is the only ingredient, with no added sugar or flavoring, and the powder is easy to add to a daily routine. Its prebiotic character may also explain why some users report gas, since fibers available to gut microbes can be fermented. A gentle prebiotic route cannot prove constipation relief here, and psyllium findings cannot simply be assigned to this formulation.
What the research supports
Wheat dextrin is a non-viscous soluble fiber with little water-holding capacity, and one evidence review describes it as having a mildly constipating effect at typical doses rather than a laxative one. A meta-analysis of 16 trials in 1,251 people found psyllium and pectin — not wheat dextrin — were the fiber types with significant effects on stool frequency and constipation treatment response. That is a meaningful distinction from psyllium-based products in this catalog: the evidence that supports psyllium for constipation does not extend to wheat dextrin, whose main evidence-backed role is as a gentle, well-tolerated fiber source rather than a constipation treatment.
What the label discloses
The label is unusually simple — wheat dextrin is the only ingredient, with the amount per serving stated on-package and no added sugar or flavoring. No third-party testing certificate or certifying organization is named.
Who this tends to suit
We match this product to people reporting constipation, irregular bowel habits and a feeling of incomplete emptying. It fits someone whose priority is regularity or a steady daily routine. Whether it is the best fit for you depends on the rest of your answers — what you have already tried, what format you will take, and anything that has to be ruled out.
Where it may not fit
The label supports gluten-free, no added sweeteners and minimal ingredient list. A powder only works if you will take it once a day, every day.
Side effects and what to be aware of
Some reviewers describe new, unpleasant gas from what they call a reformulation, though the label still lists wheat dextrin as the only ingredient and wheat dextrin is itself the prebiotic fiber. No pregnancy-specific or drug-interaction warning was found on the retailer pages checked.
Common questions
What is Benefiber?
A single-ingredient fiber powder. Wheat dextrin is the entire ingredient list, with the amount per serving stated on the pack and no added sugar or flavoring. It is a soluble, non-viscous fiber: it dissolves clear, does not thicken and has no taste, which is exactly why it does not do what psyllium does.
Does Benefiber work for constipation?
The evidence says not much. Wheat dextrin does not form a water-holding gel, so it lacks the stool-bulking mechanism psyllium has. A meta-analysis of 16 trials in 1,251 people found psyllium and pectin, not wheat dextrin, were the fibers with significant effects on stool frequency and treatment response, and one evidence review describes wheat dextrin as mildly constipating at typical doses. Its evidence-backed role is as a gentle, well-tolerated fiber source.
How do you take Benefiber, and how much?
The label dose on the unflavored powder is four teaspoons once a day, stirred into 4 to 8 ounces of any drink or soft food, which supplies 6 g of fiber. It dissolves clear and does not thicken, so it can go into coffee or soup without changing them.
Does Benefiber cause gas or constipation?
Some reviewers describe new, unpleasant gas from what they call a reformulation, though the label still lists wheat dextrin as the only ingredient, and wheat dextrin is itself a prebiotic fiber that gut microbes ferment. As for constipation, one evidence review describes wheat dextrin as having a mildly constipating effect at typical doses rather than a laxative one.
Is Benefiber gluten-free?
Yes, under 20 ppm. The label footnote explains that the wheat has been processed to meet the FDA standard for gluten-free foods. The orange-flavored variant is a different product with sweeteners, lactose from milk and colors, so the unflavored one is the single-ingredient option.
Benefiber or Metamucil?
They are two different fibers. Metamucil is psyllium, the one fiber supplement with meta-analysis evidence and a guideline behind it for constipation; Benefiber is wheat dextrin, which has no published trial in constipated patients. The Metamucil vs Benefiber comparison sets out dose, ingredients, evidence and cost per day side by side.
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Others we researched for the same job
These sit in the same role as Benefiber Daily Prebiotic Fiber Supplement Powder — stool form and regularity — so they are the sensible things to weigh it against.
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Related reading
Background on how this type of product works, read from the trial evidence.