Mineral

Iron (as Ferrous Fumarate)

Also known as: ferrous fumarate, iron(II) fumarate, Fe2+

Evidence

Ferrous fumarate is a highly bioavailable form of iron used to prevent and treat iron deficiency anemia by supporting oxygen transport and energy metabolism. It is one of the most absorbable iron salts available.

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Daily target & upper limit

18 mg / day · UL 45 mg

Iron (as Ferrous Fumarate) has an established daily reference intake. See best forms, label synonyms, upper-limit warnings, and top-scoring supplements:

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Primary uses

iron deficiency anemia treatment
anemia prevention
oxygen transport
energy production

How it works

component of hemoglobin for oxygen transport
component of myoglobin for muscle oxygen storage
cofactor in cytochrome P450 enzymes
supports cellular energy production

Dosage

Typical range: 18-27 mg elemental iron daily (adult women); 8-11 mg daily (adult men)
Timing: take on empty stomach for optimal absorption, or with small amount of food if GI upset occurs
With food: preferably without food, but avoid dairy, calcium, and coffee which reduce absorption
Duration: treatment duration depends on deficiency severity; typically several months for repletion
Special populations: pregnant women: 27 mg daily; children require age-adjusted dosing; avoid in hereditary hemochromatosis

Forms

tablet· 70/100
capsule· 70/100
liquid· 70/100

Safety

Common side effects

constipation
nausea
abdominal discomfort
dark stools
vomiting

Contraindications

hemochromatosis
hemosiderosis
repeated blood transfusions
active GI bleeding

Products containing Iron (as Ferrous Fumarate)

Top-scoring supplements in our catalog that list Iron (as Ferrous Fumarate) on the label. Each product is graded on Formulate's ingredient-level rubric — dose accuracy, form, transparency, and third-party testing.

Thorne

Iron Bisglycinate

Transparent Labs

Grass-Fed Whey Protein Isolate

Evidence notes

Iron deficiency anemia treatment is supported by extensive clinical evidence; ferrous fumarate specifically has strong bioavailability data.

Grade A: Multiple well-designed human trials support the main claims.

Related in Mineral

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Medical disclaimer. This page is educational and does not replace advice from a qualified healthcare provider.