Fiber
Resistant Starch
Also known as: RS2, RS3, Green banana starch, Raw potato starch
Starch that resists digestion and feeds colon bacteria. Supports gut health and insulin sensitivity.
Last reviewed June 2026 · Evidence graded from peer-reviewed research, not editorial opinion. Educational only — not medical advice.
Primary uses
- Gut health
- Insulin sensitivity
- Microbiome support
How it works
- Fermented to butyrate in colon
- Improves insulin sensitivity
- Feeds beneficial bacteria
Dosage
- Typical range
- 15-30 g daily
- Timing
- Any, avoid heating
- With food
- Add to cold foods
- Duration
- Start low
- Special populations
- Diabetics, gut health focus
Forms
- Raw potato starch
- Green banana flour
- Hi-maize
Safety
Common side effects
- Gas initially
- Bloating
Contraindications
- None
Evidence notes
Emerging prebiotic benefits
Grade B: Some human trials support key claims; further confirmation needed.
Related in Fiber
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Medical disclaimer. This page is educational and does not replace advice from a qualified healthcare provider. Individual needs and risks vary — consult a professional before starting, stopping, or combining supplements, especially if you are pregnant or nursing, taking medication, or managing a health condition.