NutriDex

The Supplement Research Compendium
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Resistant Maltodextrin (Soluble Corn Fiber)

Fibersol

A non-viscous, well-tolerated soluble fiber that blunts post-meal glucose, feeds bifidobacteria, and boosts calcium absorption.

Moderate evidence 🌾Prebiotics & Fibers🛡️Gut & Immune

✚ Updated · How we grade evidence

Evidence tier
Moderate
Research weight
Citations
8 verified / 8
Classification
Prebiotics & Fibers
❝
What the evidence says. Several controlled trials; effects real but modest or context-dependent.

What is Resistant Maltodextrin (Soluble Corn Fiber)?

Resistant Maltodextrin (Soluble Corn Fiber) (Fibersol) is a prebiotic fiber used for attenuates the acute post-meal rise in blood glucose and insulin in a dose-dependent way (~10-20% lower glycemic response at ~5-10 g with a carbohydrate load), the best-evidenced effect. NutriDex grades the human evidence as Moderate. Resistant maltodextrin (RMD), marketed as soluble corn fiber and under brand names such as Fibersol-2 and Promitor, is a low-viscosity, enzyme-resistant glucose polymer made by controlled heat/acid treatment of corn or wheat starch. It is highly fermentable yet largely non-gelling, so unlike viscous fibers (psyllium, beta-glucan) its main human-trial signals are a modest, dose-dependent reduction in post-meal blood glucose, a bifidogenic shift in the gut microbiome with increased short-chain fatty acids, and improved calcium absorption rather than large LDL-lowering. The best-supported use is attenuation of the acute glycemic response to a carbohydrate load (a meta-analysis of 37 RCTs); evidence for satiety, laxation, and microbiome shifts is moderate, while effects on fasting glucose, HbA1c, body weight, and lipids are smaller and less consistent. It is unusually well tolerated for a fermentable fiber, with gas and bloating typically appearing only at higher single doses.

Purported Benefits

✓Attenuates the acute post-meal rise in blood glucose and insulin in a dose-dependent way (~10-20% lower glycemic response at ~5-10 g with a carbohydrate load), the best-evidenced effect
✓Acts as a prebiotic: increases fecal bifidobacteria and other beneficial taxa (e.g. Parabacteroides) and raises short-chain fatty acid production
✓Improves calcium absorption in controlled-feeding trials, an effect linked to its microbiome-shifting (bifidogenic/fermentation) action
✓Increases satiety and delays the return of hunger after a meal, with higher GLP-1 and PYY satiety hormones at a 10 g dose
✓Supports bowel regularity, increasing stool wet weight and frequency when used to bridge a fiber-intake gap
✓May modestly lower total and LDL cholesterol, mainly when combined with a probiotic (e.g. L. rhamnosus GG) in people with elevated baseline cholesterol — a weaker, less consistent signal than for viscous fibers

Evidence by outcome

The same supplement can be well-proven for one use and unproven for another — here is the human evidence graded outcome by outcome.

OutcomeEvidenceEffectStudies
Attenuates acute post-meal glucose/insulin response37-RCT meta-analysis: dose-dependent ~10-21% lower glycemic response; the best-evidenced effect. Moderate ↑ benefit · small 1
Prebiotic/bifidogenic microbiome shiftMultiple RCTs show increased fecal bifidobacteria and SCFA; reproducible signal. Moderate ↑ benefit · moderate 4
Improves calcium absorptionCrossover RCT in adolescent girls showed ~13% higher fractional absorption; limited populations. Preliminary ↑ benefit · small 1
Increases satiety / satiety hormonesSingle small crossover RCT (n=19): 10 g raised GLP-1/PYY and delayed hunger; short-term. Preliminary ↑ benefit · small 1
Supports bowel regularity25 g/day increased stool wet weight and frequency in low-fiber adults; bridges a fiber gap. Preliminary ↑ benefit · small 1
Lowers total/LDL cholesterolOnly with a probiotic in those with elevated baseline; weaker, less consistent than viscous fibers. Mixed ↔ mixed · small 1

Dosing & Compounds

Typical Dose
Glycemic blunting: ~5-10 g taken with a carbohydrate-containing meal (often in a beverage). Prebiotic/laxation and calcium-absorption benefits: ~10-25 g/day, typically split across meals, with bifidogenic effects seen even at lower (~6-12 g/day) doses. Satiety: ~10 g with a meal. It dissolves clearly in water and is usually stirred into drinks or foods; effects are acute or build over 1-3 weeks of daily use.
Active Compounds
Fibersol-2 (Archer Daniels Midland / Matsutani) — the most-studied branded digestion-resistant maltodextrinPromitor Soluble Fiber / Soluble Corn Fiber (Tate & Lyle)Generic 'soluble corn fiber' or 'resistant maltodextrin' powders and capsulesCommon food/beverage ingredient added to fiber-fortified bars, drinks, yogurts, baked goods, and some 'fiber gummies' and keto/low-carb productsListed on US labels as 'soluble corn fiber' under the FDA-recognized dietary fibers

Safety & Cautions

One of the better-tolerated fermentable fibers: it is non-viscous and does not form a choking gel like psyllium or glucomannan, and most people tolerate 10-25 g/day. Because it is rapidly fermented, larger single doses (roughly >20-40 g) can cause gas, bloating, borderline cramping, and loose stools or osmotic/laxative effect; tolerance improves with gradual dose escalation and splitting doses. As a FODMAP-type fermentable substrate it may worsen symptoms in some people with IBS or SIBO, who should titrate cautiously. Like other fibers, taking large amounts at the same time as oral medications may slow or reduce their absorption, so separate medications by ~1-2 hours. People with diabetes on glucose-lowering drugs should monitor blood sugar, as the glycemic-blunting effect could add to medication effects. It is generally regarded as safe (GRAS) as a food ingredient; pregnant or breastfeeding people and those with significant GI disease should consult a clinician before using high supplemental doses. Educational only — always check with your doctor or pharmacist before combining Resistant Maltodextrin (Soluble Corn Fiber) with any medicine.

Key Studies

Meta-analysis of RCTs Livesey & Tagami 2009 ✓ PubMed
Across 37 randomized placebo-controlled trials, 4-10 g of resistant maltodextrin produced a significant, dose-dependent attenuation of the glycemic response to carbohydrate (e.g. ~21% reduction with rice meals; 95% CI -26% to -16%), with stronger effects in drinks than solid foods.
Randomized double-blind crossover RCT Costabile et al. 2022 ✓ Source
Resistant maltodextrin consumption induced specific increases in potentially beneficial gut bacteria, confirming a reproducible microbiome-modulating (prebiotic) signal in humans.
Randomized crossover RCT Whisner / Weaver 2016 ✓ PubMed
In 28 adolescent girls, 10 and 20 g/day soluble corn fiber increased fractional calcium absorption by ~12.9-13.3% versus control (P<0.05), with dose-dependent rises in Parabacteroides and Clostridium-related taxa.
Randomized double-blind crossover RCT Ye et al. 2015 ✓ PubMed
In 19 healthy adults, 10 g Fibersol-2 with a meal significantly delayed hunger and increased satiety for 1.5-2 h and raised satiety hormones GLP-1 and PYY versus 0 g or 5 g (P<0.05).
Randomized double-blind parallel RCT Costabile et al. 2016 ✓ Full text
In healthy adults given soluble corn fiber delivering 6, 12, or 18 g/day for 14 days, fecal bifidobacteria rose significantly at the 6 g/day dose, demonstrating a prebiotic (bifidogenic) effect.
Randomized double-blind crossover RCT Costabile et al. 2017 (Saimes) ✓ PubMed
In 40 healthy elderly adults, soluble corn fiber (alone and with L. rhamnosus GG) shifted the microbiota (increased Parabacteroides and Ruminococcaceae); the synbiotic reduced total and LDL cholesterol in those with elevated baseline levels.
Randomized double-blind crossover RCT Stewart / Baer 2018 ✓ PubMed
In healthy adults below recommended fiber intake, 25 g/day resistant maltodextrin significantly increased fecal Bifidobacterium counts and stool wet weight versus control, supporting prebiotic and laxation benefits.
Review of clinical evidence Lockyer & Stanner 2016 ✓ Source
Review of soluble corn fiber/resistant maltodextrin RCTs supports modest, fairly consistent benefits for post-meal glycemia, bifidogenic microbiome shifts and SCFA, calcium absorption, and bowel regularity, with weaker and less consistent effects on fasting glucose, lipids, and body weight.
8 sources cited · 8 verified Search all studies on PubMed ↗

Common questions about Resistant Maltodextrin (Soluble Corn Fiber)

What is Resistant Maltodextrin (Soluble Corn Fiber) used for?

Resistant Maltodextrin (Soluble Corn Fiber) is most often taken for Attenuates the acute post-meal rise in blood glucose and insulin in a dose-dependent way (~10-20% lower glycemic response at ~5-10 g with a carbohydrate load), the best-evidenced effect, Acts as a prebiotic: increases fecal bifidobacteria and other beneficial taxa (e.g. Parabacteroides) and raises short-chain fatty acid production, Improves calcium absorption in controlled-feeding trials, an effect linked to its microbiome-shifting (bifidogenic/fermentation) action, Increases satiety and delays the return of hunger after a meal, with higher GLP-1 and PYY satiety hormones at a 10 g dose. A non-viscous, well-tolerated soluble fiber that blunts post-meal glucose, feeds bifidobacteria, and boosts calcium absorption.

Does Resistant Maltodextrin (Soluble Corn Fiber) work — what does the evidence say?

Moderate evidence. Several controlled trials; effects real but modest or context-dependent. Resistant maltodextrin (RMD), marketed as soluble corn fiber and under brand names such as Fibersol-2 and Promitor, is a low-viscosity, enzyme-resistant glucose polymer made by controlled heat/acid treatment of corn or wheat starch. It is highly fermentable yet largely non-gelling, so unlike viscous fibers (psyllium, beta-glucan) its main human-trial signals are a modest, dose-dependent reduction in post-meal blood glucose, a bifidogenic shift in the gut microbiome with increased short-chain fatty acids, and improved calcium absorption rather than large LDL-lowering. The best-supported use is attenuation of the acute glycemic response to a carbohydrate load (a meta-analysis of 37 RCTs); evidence for satiety, laxation, and microbiome shifts is moderate, while effects on fasting glucose, HbA1c, body weight, and lipids are smaller and less consistent. It is unusually well tolerated for a fermentable fiber, with gas and bloating typically appearing only at higher single doses.

What is the typical dose of Resistant Maltodextrin (Soluble Corn Fiber)?

Glycemic blunting: ~5-10 g taken with a carbohydrate-containing meal (often in a beverage). Prebiotic/laxation and calcium-absorption benefits: ~10-25 g/day, typically split across meals, with bifidogenic effects seen even at lower (~6-12 g/day) doses. Satiety: ~10 g with a meal. It dissolves clearly in water and is usually stirred into drinks or foods; effects are acute or build over 1-3 weeks of daily use.

Is Resistant Maltodextrin (Soluble Corn Fiber) safe? Any cautions or side effects?

One of the better-tolerated fermentable fibers: it is non-viscous and does not form a choking gel like psyllium or glucomannan, and most people tolerate 10-25 g/day. Because it is rapidly fermented, larger single doses (roughly >20-40 g) can cause gas, bloating, borderline cramping, and loose stools or osmotic/laxative effect; tolerance improves with gradual dose escalation and splitting doses. As a FODMAP-type fermentable substrate it may worsen symptoms in some people with IBS or SIBO, who should titrate cautiously. Like other fibers, taking large amounts at the same time as oral medications may slow or reduce their absorption, so separate medications by ~1-2 hours. People with diabetes on glucose-lowering drugs should monitor blood sugar, as the glycemic-blunting effect could add to medication effects. It is generally regarded as safe (GRAS) as a food ingredient; pregnant or breastfeeding people and those with significant GI disease should consult a clinician before using high supplemental doses.

How many studies support Resistant Maltodextrin (Soluble Corn Fiber)?

NutriDex cites 8 sources for Resistant Maltodextrin (Soluble Corn Fiber), graded "Moderate".

Cite this page
APA

Peh, D. (2026). Resistant Maltodextrin (Soluble Corn Fiber) (Fibersol): Benefits, Dosage, Side Effects & Evidence. NutriDex — The Supplement Research Compendium. Retrieved 26 Jun 2026, from https://nutridex.info/s/resistant-maltodextrin

BibTeX
@misc{nutridex_resistant_maltodextrin,
  author       = {Peh, Daryl},
  title        = {Resistant Maltodextrin (Soluble Corn Fiber) (Fibersol): Benefits, Dosage, Side Effects \& Evidence},
  year         = {2026},
  howpublished = {NutriDex --- The Supplement Research Compendium},
  url          = {https://nutridex.info/s/resistant-maltodextrin},
  note         = {Reviewed by Dr Daryl Peh, MBBS Singapore, MMed FM. Accessed 2026-06-26}
}

For medical claims, citing the underlying primary studies linked above is preferred. NutriDex is an educational reference, not medical advice.

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