Iron

Tier 2 — promising · Deficiency · Fatigue · Anaemia

Affects 1.62 billion people (WHO) — the most common nutritional deficiency globally. Critical: excess iron is toxic; always test ferritin before supplementing. Ferrous bisglycinate causes far less stomach upset than ferrous sulphate. Take with 50–100 mg vitamin C to boost absorption. Separate by at least 2 hours from antibiotics, thyroid meds, and calcium.

Dose: 30–60 mg/day ferrous bisglycinate + vitamin C; test serum ferritin first; retest after 8–12 weeks