NOW Organic Inulin vs Benefiber (2026)
NOW Organic Inulin Prebiotic Powder (8 oz) and Benefiber Prebiotic Fiber Powder (wheat dextrin) both provide roughly 3 g of prebiotic fiber per serving, but they are not the same fiber. NOW is organic inulin, which ferments readily and feeds bifidobacteria — and causes gas in people who are sensitive. Benefiber is wheat dextrin, which is far better tolerated but a weaker prebiotic.
Informational comparison of label data and cost — not medical advice. Prices are per-serving figures from Amazon when checked; formulas are each brand’s published Supplement Facts.
The numbers, side by side
| NOW Organic Inulin Prebiotic Powder (8 oz) | Benefiber Prebiotic Fiber Powder (wheat dextrin) | |
|---|---|---|
| Form | Inulin (organic) | Wheat dextrin |
| Dose / serving | 3 g | 3 g |
| Serving size | 1 tsp (~3 g) | 2 tsp (~3.5 g) |
| Servings / container | 75 | 62 |
| Certification on the listing (not verified) | USDA Organic, Non-GMO | None listed |
| Price | $10.00 | $13.48 |
| Cost / day | $0.13 | $0.22 |
| Buy | Check price → | Check price → |
Prices are Amazon buy-box figures ÷ pack serving count, last reviewed October 5, 2026. Formula details are each brand’s published Supplement Facts panel.
The real difference
This is the rare comparison where the fiber type matters more than the brand. Inulin is a fructan that ferments quickly in the colon and has the stronger prebiotic evidence — studies measured an increase in bifidobacteria, which is not a proven health outcome. That fast fermentation is also exactly why it produces bloating and gas in some people, and why it is restricted on a low-FODMAP diet.
Wheat dextrin ferments slowly and much further along, which makes it markedly easier to tolerate at the cost of a weaker prebiotic effect. Despite the name it is generally considered gluten-free at the levels present, though anyone with coeliac disease should check the specific label. NOW's product is also labeled organic (not verified here); Benefiber lists no third-party certification.
Who each one is for
Choose NOW inulin if you want the fiber with the stronger prebiotic evidence and you tolerate fermentable fiber.
Choose Benefiber if you prefer wheat dextrin, which ferments more slowly than inulin.
Start low either way jumping straight to a full serving of any prebiotic fiber is the usual cause of the bloating people blame on the product. Build up over a week or two.
Our picks
Organic inulin, the more researched prebiotic fiber. $0.13/day.
Wheat dextrin, gentler on the gut with less gas. $0.22/day.
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Frequently asked questions
Is inulin or wheat dextrin better?
Inulin has the stronger prebiotic evidence, with studies measuring an increase in bifidobacteria (not a proven health outcome), but it ferments quickly and causes gas and bloating in sensitive people. Wheat dextrin ferments slowly, is much better tolerated, and is the weaker prebiotic. Tolerance usually decides it rather than potency.
Is Benefiber gluten free?
Wheat dextrin is derived from wheat but is generally considered gluten-free at the levels present in the finished product. Anyone with coeliac disease should confirm against the specific label rather than rely on the general case.
Why does fiber make me bloated?
Fermentable fibers like inulin are broken down by gut bacteria that produce gas as a by-product. The effect is dose-dependent and usually eases as the microbiome adapts, which is why building up gradually rather than starting at a full serving matters.
Related
- All fiber products — ranked by cost per gram
- Psyllium husk products — the bulk-forming alternative
- Fiber guide — types, doses and what each is for
Sources
- Product labels: manufacturer Supplement Facts panels for both products, plus Amazon pricing.
- Monash University FODMAP programme on fructans and tolerance. monashfodmap.com
- Product labels and Amazon pricing for both products, as of the price date shown on this page.