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Gut & Microbiome

resistant starch decreases body weight

In plain terms: Does resistant starch help you lose weight?

Leans against Gut & Microbiome 🔬 Includes disconfirming

Part of: 🧪 resistant starch

RefutedContestedStrong support
consensus score -0.24

Probably not — most trials show little to no weight loss, with one small promising study not yet replicated.

📅 Last reviewed: 2026-07-15

Evidence ladder

How far up the ladder this claim has climbed. A high consensus on a low rung means "consistent so far," not "proven in people."

Top evidence so far: All trials, pooled (Meta-analysis)

MechanismIn-vitroAnimalObservationalRCTMeta-analysis

How the studies fall

5 support 9 contradict 4 tested null 1 mixed · 19 sources, 14 independent groups

What the evidence shows

RS produced ~2.8 kg weight loss + improved insulin resistance over 8 wk in overweight/obese adults, mediated by microbiota change — promising but single small cohort, not yet replicated across populations.

The evidence (19)

SourceGradeStanceQualityFinding
Klosterbuer
2012 · J Agric Food Chem
RCT contradicts low RS reduced glucose/insulin/GLP-1 but no effect on satiety in healthy humans
Connolly KR et al
2026 · study_type: animal
animal contradicts low Weaned piglets, resistant potato starch (PS)-only arm: PS alone reduced ADFI (feed intake, p<0.10) and did not enhance growth/weight vs control; only PS+butyric-acid combination improved ADG/BW.
Im ST et al
2026 · study_type: animal
animal supports moderate HFD-induced obese mice fed RS-enriched high-amylose rice (R-HAR): long-term supplementation significantly reduced body weight gain and adiposity vs HFD control (no kg/CI given in abstract).
Cao
2022 · Nutrients
RCT tested-null low RS potatoes improved gut permeability but body mass unchanged over 2 wk
Oluseyifunmi IW et al
2025 · study_type: animal
animal contradicts low Broiler chickens, mixed-Eimeria model: 25 g/kg raw potato RS increased starter-phase weight gain vs control (P=0.047); no overall reduction in body weight from RS.
Kim
2025 · Nutrients
RCT contradicts low RS pilot in women with MetS risk; metabolic/microbiota endpoints, small pilot
Li H, et al. (Zhao/Jia)
2024 · Nat Metab
RCT supports high Mean -2.8 kg + improved IR over 8 wk; n=37 crossover, single Chinese cohort
Guo 2021
2021 · Crit Rev Food Sci Nutr
meta-analysis contradicts moderate RS had NO direct effect on body weight/composition in humans
Gower
2016 · Nutr Metab
RCT tested-null low HAM-RS2 effects modulated by baseline insulin sensitivity; no consistent benefit in women
Emilien
2017 · Nutrition
RCT contradicts low resistant wheat starch no effect on appetite or food intake in healthy adults
Al-Mana
2018 · Nutrients
RCT tested-null low acute 48g RS did not reduce food/energy intake in overweight/obese males
Gao
2019 · Lipids Health Dis
meta-analysis contradicts moderate RS meta improves insulin resistance in obese T2DM; weight/BMI effects controversial
Jaroenporn S et al
2026 · study_type: animal
animal supports moderate Wistar rats, HFD+RS3 (cassava) vs HFD-native-starch, 28d, isocaloric intake: HFD-RS3 had significantly lower body-weight gain, liver weight, visceral fat vs HFD-NS despite comparable calories (values not quantified in abstract).
Tian K et al
2026 · study_type: animal
animal contradicts moderate Duplicate of the lamb RS study (meatsci.2025.110021): RS group exhibited higher body weight and average daily gain vs native-starch group over 56-day finishing trial.
Liu J et al
2026 · study_type: animal
animal supports moderate HFD-induced obese mice, 8-week medium-dose corn RS1: body weight reduced by 23.7% (p<0.05) vs HFD control, with reduced fat/liver mass.
White
2020 · J Acad Nutr Diet
RCT contradicts moderate RS2 no effect on appetite or food intake in prediabetes; undercuts satiety-to-weight
Snelson 2019
2019 · Nutrients
meta-analysis tested-null moderate RS2 lowered TG but no significant body-weight effect (22 RCTs)
Davies M et al
2025 · bioRxiv
RCT supports low Overweight/obese dogs, 30d crossover, RS-containing supplement vs placebo: significant weight loss (0.45±0.57 kg, P=0.002) and BCS reduction (P=0.009) in 17/21 dogs.
Johnstone
2020 · J Nutr
RCT mixed moderate nondigestible carbs incl RS post-weight-loss affected satiety/metabolic markers

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