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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