Sorbitol is both a sweetener people eat and a substance the body makes. It softens stool and moves it through the gut faster, raises blood sugar far less than table sugar, and modestly reduces tooth decay. Bloating and loose stool follow predictably above roughly 10 to 20 grams daily. It also reduces absorption of some swallowed medicines. (Full Review)
| Marker | Target | Why |
|---|---|---|
| Bristol Stool Form Score | 3 to 4 | Primary success measure for laxative use |
| Serum potassium | 4.0 to 4.5 mmol/L | Detects osmotic potassium loss |
| Serum sodium | 138 to 142 mmol/L | Detects dehydration from fluid shift |
| eGFR | Above 90 mL/min/1.73 m² | Sets tolerance for fluid and electrolyte loss |
| Fasting blood glucose | 70 to 85 mg/dL (3.9 to 4.7 mmol/L) | Confirms benefit of substituting sorbitol for sugar |
| HbA1c | 4.8 to 5.4% | Confirms the substitution held over time |
| Sorbitol hydrogen breath test, peak rise | Below 20 ppm above baseline | Identifies malabsorbers needing half doses |
| Fasting plasma sorbitol | No established consumer target; track change from the individual's own baseline | Relevant only where SORD deficiency is suspected |
Cadence: Symptoms and stool form weekly during titration, then monthly. Electrolytes and kidney function at four weeks of daily laxative-range dosing, then every six to twelve months, and more often alongside diuretics. HbA1c at three months where sugar substitution is the goal.