Iron
Plain-language research summary.
Detail
bloodenergymetabolismwomens-health
Essential trace mineral for oxygen transport, energy metabolism, and red blood cell production — particularly important for women of reproductive age.
Common Dietary Sources
- Red meat, poultry, and seafood (heme iron)
- Lentils, beans, spinach, and fortified cereals (non-heme iron)
- Iron cookware (adds small amounts during cooking)
How the Body Uses It
Iron is the core element of hemoglobin and myoglobin, the proteins that carry oxygen in blood and muscle. It also supports mitochondrial energy metabolism and cognitive function. The body recycles iron efficiently, but women lose significant amounts during menstruation.
Supplement Origins
Supplemental forms include ferrous sulfate (common), ferrous bisglycinate (gentler on digestion), and heme iron polypeptide (derived from animal sources with high absorption). Plant-based forms are less efficiently absorbed but improved with vitamin C intake.
Possible Uses
- Correcting iron deficiency or iron-deficiency anemia
- Supporting energy and oxygen delivery in athletes and menstruating women
- Preconception and prenatal supplementation under medical guidance
Long-Term Use
Long-term use should be based on confirmed need (blood testing). Excessive iron can accumulate in tissues and increase oxidative stress. Women often benefit from periodic lab evaluation of ferritin and hemoglobin.
Dose Guidance
Studied
18 mg/day for adult women; 8 mg/day for adult men (RDA)
Take on an empty stomach or with vitamin C to improve absorption. Avoid taking with calcium, coffee, or tea, which can reduce absorption.
Forms
Ferrous sulfate
Standardization: 20% elemental iron; most common, may cause GI upset
Ferrous bisglycinate
Standardization: Gentle chelated form with higher absorption and fewer side effects
Heme iron polypeptide
Standardization: Derived from animal sources; highly bioavailable, typically used in clinical deficiency
Delivery
Coming soon.
Evidence & Studies
Improved hemoglobin and fatigue scores in menstruating women with iron deficiency
Reduced risk of anemia and low birth weight when supplemented during pregnancy
References
Safety & Cautions
Cautions
- May cause constipation, nausea, or dark stools
- Monitor ferritin and hemoglobin to avoid overload
Contraindications
- Hemochromatosis or iron overload disorders
Interactions
- Calcium, coffee, and tea inhibit absorption
- Vitamin C enhances absorption
- May interact with thyroid medications and certain antibiotics