By goal
Evidence-Backed Supplements for Iron Deficiency and Anemia
Iron deficiency is the world's most common nutrient shortfall, and when it tips into anemia it brings fatigue, breathlessness and poor concentration, so many people reach for supplements to rebuild their blood. The evidence is genuinely strong for nutrients that fix specific deficiencies. Iron is the cornerstone, but only when bloodwork confirms you are low. Vitamin B12 and folate are firmly established for the anemias they each cause, while copper and vitamin A are essential, less-recognised cofactors in iron metabolism and red-cell formation. Vitamin C has moderate support, mainly for helping the gut absorb non-heme iron. Beetroot is studied more for exercise and blood pressure than for anemia. Others are weaker: spirulina and ejiao (donkey-hide gelatin) rest on preliminary data, and dong quai's blood-building claims are mixed. We grade each by what trials actually show, with dosing and safety notes. This page is educational and not medical advice; talk to your doctor or pharmacist before starting iron, since unnecessary supplementation can cause harm.
| Supplement | Evidence for this goal | Typical dose | Key caution | Studies |
|---|---|---|---|---|
| Copper | Strong for this goal | Adult RDA 900 mcg/day (0.9 mg); pregnancy 1,000 mcg, lactation 1,300 mc… | UL is 10 mg/day (US IOM); acute overdose causes nausea, vomiting, abdominal pain, and can p… | 8 |
| Folate / Folic Acid | Strong for this goal | 400-800 mcg/day for anyone who could become pregnant (start >=1 month b… | Folic acid is generally very safe at recommended doses; the tolerable upper intake level fo… | 13 |
| Iron | Strong for this goal | Treatment ~40–60 mg elemental; alternate-day dosing may absorb better.… | Constipation, nausea and dark stools are common. | 17 |
| Vitamin A (Retinol / Beta-Carotene) | Strong for this goal | Adult RDA: 900 mcg RAE/day (men), 700 mcg RAE/day (women); ~770 mcg in… | Preformed vitamin A is fat-soluble and accumulates; chronic intake above the 3,000 mcg/day… | 8 |
| Vitamin B12 | Strong for this goal | 2.4 µg/day RDA; deficiency corrected with high oral (500–1,000 µg) or i… | Very safe; excess excreted. | 23 |
| Beetroot / Dietary Nitrate | Moderate | ~6-13 mmol (≈310-800 mg) inorganic nitrate per day, typically as 1-2 co… | Generally well tolerated. | 18 |
| Vitamin C | Moderate for this goal | 75–90 mg/day RDA; 200 mg saturates tissues. Doses >1g mostly excreted. | Safe. | 21 |
| Dong Quai | Preliminary for this goal | Commonly 3–15 g in decoction or formula; rarely used alone in TCM. | May increase bleeding (avoid with anticoagulants) and photosensitivity. | 17 |
| Ejiao (Donkey-hide Gelatin) | Preliminary for this goal | Traditionally 3–9 g dissolved in warm liquid; few standardized human st… | Gelatin itself is low-risk to consume. | 15 |
| Spirulina | Preliminary | Commonly 1-8 g/day (some trials up to ~10 g/day) of dried Arthrospira,… | Generally well tolerated short-term; mild GI upset, headache, or allergic-type reactions ca… | 16 |