Ultimate Longevity Bible

Nutrition topic

Resistant Starch

Last updated 2026-07-02· Last reviewed 2026-07-02· 1 min read

Reviewed by the Ultimate Longevity Bible editorial team. Educational reference — not medical advice. See disclaimer.

Types

  • RS1: physically inaccessible (whole grains, seeds).
  • RS2: native granular structure (raw potato, unripe banana).
  • RS3: retrograded — formed when cooked starch cools (cooked-then-cooled potatoes, rice, pasta).
  • RS4: chemically modified (industrial).

Evidence

  • Improves insulin sensitivity in cross-over trials.
  • Reduces post-prandial glucose excursion when substituting for rapidly-digested starch.
  • Consistent increases in fecal butyrate and butyrate-producer abundance.

Practical

  • Cooking rice, potato, pasta, then cooling and refrigerating overnight produces meaningful RS3 that is retained on gentle reheating.
  • 15–30 g/day of RS is a reasonable target; RS supplements (potato starch, Hi-maize) are available.
  • Ramp up slowly to allow microbiome adaptation.

More on this topic

Related entries

Butyrate, Fibre and microbiome, Continuous glucose monitoring, Legumes.

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