Resistant starch, a dietary starch in green bananas, beans, cooled cooked rice or potatoes and inexpensive powders, escapes digestion, feeds gut bacteria and is used to improve blood sugar control. Replacing ordinary starch, it most consistently lowers post-meal blood sugar. Daily use brings small, inconsistent fasting blood sugar and cholesterol gains, clearest with insulin resistance or excess weight. Main drawbacks: gas, bloating and food poisoning from cooked starch left warm. (Full Review)
| Marker | Target | Why |
|---|---|---|
| Fasting glucose | 70–99 mg/dL | Small fall with sustained intake |
| Fasting insulin / HOMA-IR | Fasting insulin 2.6–24.9 µIU/mL; HOMA-IR: no established target, track change from own baseline | Insulin resistance may fall |
| HbA1c | 4.0–5.6% | At most a slight fall |
| LDL cholesterol | No established target; track change from own baseline | Small fall expected |
| ALT | 7–56 U/L | May fall in people with fatty liver |
| Body weight and waist circumference | No established target; track change from own baseline | Modest fall in some trials |
| Self-monitored glucose (people on insulin or sulfonylureas) | 70 mg/dL or higher | Safety check for low blood glucose |
Cadence: Baseline panel before starting; daily glucose checks for the first 2 weeks on insulin or sulfonylureas; weekly weight and waist; fasting glucose, insulin and lipids at 8–12 weeks, then every 6–12 months