Resistant starch (prebiotic)

Tier 2 — promising · Gut microbiome · Glucose · Satiety

Starch that escapes small-intestine digestion and ferments in the colon, feeding beneficial bacteria and producing short-chain fatty acids including butyrate, which supports colonocyte health and reduces gut inflammation. The 2023 Pugh meta-analysis of 36 RCTs (N=982, PMID 37051127) found RS types 1 and 2 significantly lower acute postprandial blood glucose (SMD -0.54 to -0.96) and RS type 2 improves fasting glucose and insulin in people with type 2 diabetes or prediabetes. Natural sources include green banana flour, cooked-then-cooled potatoes and rice, and raw potato starch. Heat…

Dose: 15–30 g/day; from food or 10–30 g raw potato starch; start at 5 g/day to allow gut adaptation