A seaweed-derived fiber that passes through the gut unabsorbed and grips metal ions. It measurably reduces radioactive strontium uptake from a meal, relieves heartburn, though how much is disputed, blunts the rise in blood sugar after a meal and modestly lowers cholesterol. Removing metal already stored in the body has never been tested against a placebo. Iron absorption falls. (Full Review)
| Marker | Target | Why |
|---|---|---|
| Ferritin | 50–100 ng/mL (women 50–90 ng/mL) | Earliest signal of iron depletion |
| Complete blood count | Hemoglobin 13.5–15.0 (men), 12.5–14.0 (women) g/dL; mean corpuscular volume 85–92 fL | Whether falling iron reached the red cells |
| Thyroid-stimulating hormone | 0.5–2.0 mIU/L | Iodine-driven thyroid disturbance from algal material |
| Urinary iodine concentration | 100–199 µg/L | Iodine load from seaweed-derived material |
| Serum potassium | 4.0–4.5 mmol/L | Added potassium load from potassium alginate |
| Estimated glomerular filtration rate | Above 90 mL/min/1.73 m² | Whether potassium or mineral load is cleared |
| Blood lead | Below 1.0 µg/dL | The most interpretable toxic-metal marker |
| Urine cadmium and mercury | Cadmium below 0.5 µg/g creatinine; mercury below 3 µg/L | The other two metals alginate binds in vitro |
| Fasting lipid panel | LDL cholesterol below 80 mg/dL; triglyceride-to-HDL ratio below 2.0 | Captures the best-supported metabolic benefit |
| Fasting glucose and HbA1c | Glucose 75–85 mg/dL; HbA1c below 5.4% | Whether acute glycemic effects are durable |
| 25-hydroxyvitamin D | 40–60 ng/mL | Fat-soluble vitamin loss from fecal fat |
| Serum sodium and home blood pressure | Sodium 137–142 mmol/L; blood pressure below 120/80 mmHg | Sodium load and blunted pressure response |
Cadence: Baseline before starting; ferritin, complete blood count and thyroid-stimulating hormone at 3 months, then every 6 months; lipid and metal panels at 3 months; home blood pressure fortnightly for the first 3 months on sodium alginate.