Resistant starch

Also known as RS, potato starch fibre, green banana starch.

Last reviewed October 9, 2026 · Jump to references

What is Resistant starch?

In plain words

Resistant starch is starch that escapes digestion in the small intestine and acts like fibre. Bacteria in the large intestine break it down, making substances that help feed the gut lining. Researchers study it for gut health, blood sugar control and how full people feel after eating. Effects vary by starch type and person, and it can cause gas or bloating.

Technical definition

Resistant starch is a dietary fibre comprising glucose polymers in starch that resist digestion in the small intestine because of their physical accessibility, granular structure, retrogradation or chemical modification. It has no single receptor target; colonic microbes ferment it into short-chain fatty acids, including butyrate, which supports colonocytes and participates in signalling through receptors such as FFAR2 and FFAR3. It is a food component rather than an approved therapeutic drug, and eligibility for dietary-fibre labelling depends on the ingredient and jurisdiction.

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Evidence by use

Each use is rated on its own. There is no single overall effectiveness score.