18–27 mg elemental iron daily, taken on an empty stomach with vitamin C (e.g., orange juice) for optimal absorption. If stomach upset occurs, take with a light meal, though absorption will be slightly reduced.

15–30 mg daily with food to minimise nausea. Do not exceed 40 mg/day without medical supervision, as chronic high-dose zinc can cause copper deficiency and worsen hair loss.

2500–5000 mcg daily, taken with a meal. Start at the lower end and increase if tolerated.

500–1000 mcg daily in the morning with food. Sublingual (under-the-tongue) forms bypass stomach acid and are ideal if you take PPIs or have absorption issues.