Mineral
Iron (as Fermented Iron Bisglycinate)
Also known as: iron bisglycinate, fermented iron, chelated iron
Iron is an essential mineral critical for oxygen transport and fetal development during pregnancy. The bisglycinate chelate form offers enhanced absorption and bioavailability with reduced GI irritation compared to ferrous salts.
Primary uses
- Oxygen transport
- Prevention of gestational anemia
- Fetal development and birth weight support
- Energy metabolism
How it works
- Component of hemoglobin and myoglobin
- Cofactor for iron-dependent enzymes
- Chelation improves intestinal absorption
- Reduced ionic irritation to GI tract
Dosage
- Typical range
- 27 mg daily (RDA for pregnant women)
- Timing
- morning on empty stomach preferred for absorption, but can take with food if GI upset occurs
- With food
- separate from calcium, zinc, and polyphenols by 2 hours when possible; vitamin C enhances absorption
- Duration
- throughout pregnancy and postpartum; continue if breastfeeding
- Special populations
- Pregnant women 27 mg/day; lactating women 9–10 mg/day; dosage may increase if anemia confirmed
Forms
- iron bisglycinate· 70/100
- ferrous fumarate· 70/100
- ferrous sulfate· 70/100
Safety
Common side effects
- constipation
- nausea
- dark stools
Contraindications
- Hemochromatosis
- sickle cell disease without supplementation indication
Evidence notes
Extensive RCT evidence for iron supplementation in pregnancy; strong evidence that adequate iron prevents anemia and poor birth outcomes; chelated forms reduce side effects while maintaining efficacy.
Grade A: Multiple well-designed human trials support the main claims.
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