Iron deficiency from heavy periods: the missed diagnosis

Iron deficiency is the most common nutritional deficiency in women of reproductive age. Heavy periods are the leading cause. Many women feel run-down for years before getting diagnosed, because clinicians check hemoglobin (which can be normal) but skip ferritin (which is often low).

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Symptoms women dismiss

Exhaustion that does not match how much you sleep. Brain fog. Cold hands and feet. Pale skin or inner lower eyelids. Restless legs. Hair shedding more than usual. Brittle nails. Craving ice (pagophagia). Shortness of breath on stairs.

The labs to ask for

CBC (gives hemoglobin and hematocrit). FERRITIN (the storage iron - this is the missed one). Transferrin saturation. Below 30 ng/mL ferritin = iron deficient even with normal hemoglobin. Optimal is closer to 50 to 100 ng/mL.

Iron supplementation that works

65 mg elemental iron (ferrous sulfate 325 mg) per dose. New research: every other day is better absorbed than daily. Take with vitamin C (orange juice, a kiwi). Keep away from coffee, tea, calcium, and thyroid meds (4 hour gap). Constipation is common - magnesium citrate or stool softener helps.

When oral iron is not enough

If ferritin stays low after 3 months of oral iron, or you cannot tolerate it, IV iron infusions are highly effective and increasingly easy to access. Insurance usually covers when ferritin is below a threshold (varies by plan).

Common questions

Can low iron cause anxiety? +

Yes. Iron deficiency affects neurotransmitter production. Many women report anxiety improving when their ferritin goes from 15 to 50.

How long to feel better after starting iron? +

Energy improvements often appear in 4 to 6 weeks. Full restoration of stores takes 3 to 6 months.

Does iron in food help? +

Heme iron (red meat, organ meat) absorbs much better than non-heme (plants). Vegans/vegetarians often need supplementation to keep up with menstrual losses.