Iron for Women: When You Need It (And When You Don't)

Roughly 1 in 5 women of menstruating age has low iron, yet most don't know. Here's how to know, how to test, and how to fix it safely.

Iron is the most common nutrient deficiency in the world, and it disproportionately affects menstruating women, vegetarians, vegans, and endurance athletes.

If you're tired, pale, breathless on stairs, or have brittle nails, iron should be on your radar.

The numbers

• About 20% of women of reproductive age are iron-deficient
• 50% of pregnant women globally are iron-deficient
• Plant-based eaters absorb iron at about 1/3 the rate of meat eaters

Signs of low iron

• Persistent fatigue (not improved with sleep)
• Pale skin, especially inside lower eyelids
• Cold hands and feet
• Brittle, ridged, or spoon-shaped nails
• Hair shedding
• Restless legs at night
• Breathlessness or fast heartbeat on minor exertion
• Strange cravings (ice, dirt, paper), pica

Test before you supplement

Iron supplements taken unnecessarily can cause oxidative stress and digestive distress. Get a blood panel that includes:

• Ferritin, stored iron (most useful single marker; aim for >50 ng/mL)
• Hemoglobin / hematocrit, current red blood cell capacity
• Transferrin saturation, how well iron is being shuttled

If you're low, how to supplement

Standard iron supplements (ferrous sulfate) work but commonly cause nausea, constipation, and stomach upset. Better-tolerated forms:

• Iron bisglycinate (gentle iron), 25 mg daily
• Heme iron polypeptide, well-absorbed, animal-derived
• Liquid iron from whole-food sources, e.g. Floradix

How to take it:

• On an empty stomach if tolerated (better absorbed)
• With 500 mg of vitamin C (boosts absorption ~3x)
• Avoid coffee, tea, calcium, and dairy within 1 hour
• Alternate days may be MORE effective than daily (recent research)

Foods rich in iron

• Red meat (especially organ meats)
• Shellfish
• Lentils, beans, tofu
• Dark leafy greens
• Pumpkin seeds
• Dark chocolate

Don't supplement iron 'just in case', too much is toxic. Test first.

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