Modified citrus pectin, a dietary supplement of citrus-peel fiber cut into small fragments, is promoted to block a protein linked to tissue scarring and cancer spread. Animal and laboratory studies are encouraging, but in people, studies without comparison groups report slower rises in a prostate cancer blood marker and more urinary loss of toxic metals, while the few trials against placebo found no benefit. Risks appear modest, mainly digestive complaints. (Full Review)
| Marker | Target | Why |
|---|---|---|
| Serum potassium | 3.5–5.0 mmol/L | Safety check: rise would pause use |
| eGFR / serum creatinine | Serum creatinine about 0.6–1.3 mg/dL; eGFR >59 mL/min/1.73 m²; track change from own baseline | Safety check: decline would stop use |
| PSA and PSA doubling time (men with prostate cancer) | PSA 0.0–4.0 ng/mL; track doubling time against own pre-treatment trend | Expected to change: main outcome in prostate trials |
| Blood lead (if used for metal exposure) | 0.0–3.4 µg/dL; track change from own baseline | Expected to change: outcome in metal-excretion studies |
Cadence: Baseline, week 6, then every 3–6 months for potassium and kidney function; PSA every 3 months in men with prostate cancer; blood lead after 4 weeks of a metal-focused course