Supplement evidence

079 / 575Fiber & digestive

Resistant starch

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The short answer

A fermentable starch studied for bowel function, insulin sensitivity, and microbiome effects.

Evidence and scope: Conditional or population-specific
This status does not grade the ingredient for every goal, outcome, or person.
Important limitation: Benefit depends on the population, formulation, baseline status, and objective; results should not be generalized.
Before deciding: Key concern: May worsen bloating or IBS symptoms; glucose responses vary by product and meal.

01 / PRACTICAL GUIDE

Dose, absorption, and combinations

These are indication-specific reference or studied ranges—not a personalized prescription. Start with the objective, then check the form, label, medicines, and health conditions.

Reference range by objective

Meal-specific digestionStart 5 g/day; trials often use 15–30 g/day

Reference or studied range—not a personalized prescription. The product label or a clinician may specify a different dose.

Dose source ↗

More is not automatically better. A clinician or product label may specify a different amount.

Absorption / solubilityFat/water classification is not the key factor

Fat/water solubility is not the useful decision point; preparation, fluid, timing, or strain identity matters more.

How it is commonly taken

Increase slowly and maintain fluid intake.

Do not combine casually

May worsen bloating or IBS symptoms; glucose responses vary by product and meal.

Dose and use source ↗

Dose and use links lead to primary or official source material. Search links are discovery tools, not proof that every returned paper applies.

02 / EVIDENCE

What the research says

We keep supportive, mixed, negative, safety, and contextual findings together. The headline never replaces the underlying papers.

3research papers in this ledger

14unique primary studies represented

474unique participants represented

These are audited counts for this JIVANA collection, not search-result totals. Participants are counted once when multiple papers use the same cohort; review papers are not added again to participant totals.

Open the research timelineResearch timeline

Entries are ordered by publication year. A study period appears only when the source reports it.

2025

Does not support the tested claimPMID 40156576 · UMIN000052543

Wheat resistant starch and bowel movements in healthy adults

The prespecified primary endpoint, defecation frequency, did not improve. Favorable subgroup findings in people with incomplete evacuation were exploratory and do not establish overall efficacy.

Published: 2025Duration: Two 4-week periods separated by a 4-week washoutn=46 participants

Study design and methods

Design: Randomized, double-blind, placebo-controlled crossover trial
Population: 46 healthy Japanese adults
Intervention: Bread providing 3.26 g/day wheat-derived resistant starch versus control bread
Outcome: Defecation frequency and bowel symptoms

Funding or conflict note: Four of five authors were affiliated with Nisshin Seifun Group.

Open research record ↗

2019

Mixed or qualifiedPMID 31168050

Effects of resistant starch on glucose, insulin resistance, and lipid parameters

Pooled estimates favored resistant starch for several glycemic and insulin measures and modestly for LDL, but the authors cautioned about individual and microbiome variation. Small heterogeneous studies do not establish a uniform effect for every resistant-starch type.

Published: 2019n=428 participants13 primary studies represented

Study design and methods

Design: Systematic review and meta-analysis of 13 controlled studies
Population: 428 adults with BMI at least 25, including diabetic and nondiabetic groups
Intervention: Resistant-starch supplementation versus control; starch type, dose, and duration varied
Outcome: Fasting glucose and insulin, insulin resistance or sensitivity, HbA1c, and lipids

Funding or conflict note: The authors declared no conflicts of interest.

Open research record ↗

2017

Mixed or qualifiedPMID 27593182

Resistant starch supplementation and bowel function in healthy adults

Fecal wet weight and butyrate increased and fecal pH fell, but defecation frequency did not clearly improve. Because the abstract omitted audit-ready totals and likely overlaps the metabolic evidence base, this is context-only.

Published: 2017

Study design and methods

Design: Systematic review and meta-analysis of randomized trials
Population: Healthy adults; the abstract did not report aggregate participants or trial count
Intervention: Resistant starch versus control
Outcome: Fecal weight, defecation frequency, stool chemistry, and butyrate

Open research record ↗

Unscreened discovery appendix—not evidence239 candidate publicationsSearch run: Aug 21, 2026

Complete for the displayed PubMed query at the search timestamp—not for all databases or every possible synonym. Candidates can be irrelevant, duplicate the same study, or report negative findings. They are never summed as evidence or participants until screened.

03 / SOURCES

Start with the source material

Official evidence overviewPubMed bounded human-evidence search Live PubMed discovery searchNational Library of Medicine

The live search is for discovery only. Search-result counts change and are not included in the audited totals above.

Recent PubMed discovery recordsDirect links to the first 12 records returned by the reproducible search. These are discovery candidates—not reviewed summaries or a count of supportive findings.

04 / EXPERT CONTEXT

Expert context—not evidence

Expert positions are dated context—not scientific evidence. They never raise the evidence status or become consensus by repetition.

No direct, source-verified endorsement is currently recorded. Research authorship or discussion alone is not treated as endorsement.