Iron deficiency is the most common nutritional deficiency in the world, and it’s one of the most common causes of hair loss I see — especially in women. If your hair is thinning and you haven’t had your iron checked recently, that’s step one.
Why iron matters for hair
Your hair follicle needs a steady supply of oxygen-rich blood to function properly. Iron is essential for hemoglobin production — hemoglobin carries oxygen in your blood. When iron is low, your body prioritizes oxygen delivery to vital organs. Hair follicles are not vital organs. They get cut off first.
The result is follicles entering the resting phase prematurely, which shows up as diffuse thinning — not bald spots, but an overall decrease in density. Your part looks wider. Your ponytail feels thinner. You notice more hair in the drain.
The numbers your doctor might miss
Here’s the thing that frustrates me: a lot of doctors will look at standard iron labs and say “you’re fine” when you’re actually not fine for hair growth purposes. Standard hemoglobin levels might be in range, but your ferritin — your stored iron — could be tanked.
Dermatologists and trichologists generally want to see ferritin above 40 ng/mL for healthy hair growth. Many doctors consider anything above 12 “normal.” That’s normal enough to not have anemia. It’s not normal enough for your hair to thrive.
Ask specifically for a ferritin test. If it’s below 40, you have your answer — even if your doctor says it’s “fine.”
Who’s most affected
Women with heavy periods. This is the number one cause of iron depletion in premenopausal women. Monthly blood loss directly depletes iron stores, and most women don’t eat enough iron-rich food to keep up.
Vegetarians and vegans — plant-based iron (non-heme) is harder to absorb than animal-based iron (heme). You need to eat significantly more of it to get the same benefit.
Endurance athletes, particularly runners. Regular intense exercise increases iron requirements through sweat loss and something called foot-strike hemolysis.
Pregnant and postpartum women. Growing a human takes a lot of iron, and most women don’t fully replenish their stores for months after delivery — one reason postpartum shedding can be so dramatic.
How to fix it
Diet first: red meat is the most efficient source. Liver, if you can stomach it, is even better. Shellfish, dark leafy greens, lentils. Pair plant-based iron with vitamin C (lemon juice on your spinach, for example) to dramatically improve absorption.
Supplementation if needed. Iron bisglycinate is generally better tolerated than ferrous sulfate (fewer stomach issues). Take it on an empty stomach with vitamin C, away from coffee and dairy which inhibit absorption.
Expect it to take 3–6 months of consistent supplementation to see hair changes. Building iron stores takes time, and your hair won’t respond until levels are adequately restored.
What we do in the meantime
While your iron levels rebuild, we can help cosmetically. Strategic cutting to add volume and movement. Davines Naturaltech Energizing scalp treatments to support the follicles topically. Styling techniques that create the appearance of fullness.
The important thing is addressing the cause, not just masking the symptom. Come see us at Reverie — we’ll be honest about what we’re seeing and whether it’s time to involve your doctor.
