Hair Loss and Iron Deficiency: The Link Most People Miss

TL;DR:

• Iron deficiency is one of the most common causes of hair loss in women — and one of the most frequently missed
• Ask specifically for a ferritin test, not just a full blood count. Ferritin is the stored iron that hair follicles depend on
• Your ferritin can be technically "in range" but still too low for healthy hair growth — most trichologists recommend 70–80 μg/L as the target
• Shedding typically slows 2 to 3 months after ferritin levels begin to recover. Full regrowth takes 6 to 12 months
• Support your scalp with professional products while your levels recover — the two approaches work together

If your hair is shedding and you can't figure out why, check your iron — specifically your ferritin. Iron deficiency is one of the most common causes of hair loss in women, and it's remarkably easy to miss because it doesn't always show up as obvious fatigue or pale skin. Sometimes hair loss is the only sign.

A note on expertise: This article explains the connection between iron and hair loss and what to do about it. For diagnosis and treatment, please consult your GP. Our stylists can advise on scalp care products while you address the nutritional side of things.

01 — How Iron Deficiency Causes Hair Loss

Iron plays a critical role in producing haemoglobin — the protein in red blood cells that carries oxygen to your body's tissues, including your hair follicles. When iron levels are low, your body prioritises oxygen delivery to vital organs. Hair follicles — not essential for survival — get deprioritised. The result: follicles shift from the active growth phase into the resting phase, leading to increased shedding. This is a form of telogen effluvium triggered by nutritional deficiency.

02 — The Difference Between Iron and Ferritin

This is where most people — and even some GPs — get tripped up. A standard blood test might show your iron levels as "normal" while your ferritin (stored iron) is actually low. Ferritin is what your body draws on when iron intake is insufficient. Hair follicles are particularly sensitive to low ferritin — even when serum iron looks fine.

If you're investigating hair loss, ask specifically for a ferritin test, not just a full blood count. Many doctors won't include it automatically. And when you get the result, look at the actual number. Most trichologists recommend a ferritin level of at least 70 to 80 μg/L for optimal hair growth — significantly higher than the standard lab "normal" range, which can be as low as 12 to 15 μg/L.

"This is probably the most common thing we see — clients who have had blood tests and been told they're fine, but when you dig into the ferritin number, it's 18 or 20," says Lewis. "That might be technically in range, but it's not enough to support healthy hair growth. The number matters more than the label."

03 — Who Is Most at Risk

Women with heavy periods (the most common cause of iron deficiency in women of reproductive age) — pregnant and postpartum women (iron demands increase significantly during pregnancy) — vegetarians and vegans (plant-based iron is less easily absorbed than animal-based iron) — people with gut conditions like coeliac disease or IBS that impair iron absorption — frequent blood donors.

04 — Other Symptoms of Iron Deficiency

Hair loss can be the only symptom — but you might also notice fatigue and low energy even after a full night's sleep, brittle nails, pale skin or pale inner eyelids, shortness of breath with mild exertion, difficulty concentrating, cold hands and feet, and restless legs at night.

05 — What to Do About It

Get tested. Ask your GP for a full blood count, serum ferritin, serum iron, and transferrin saturation. Don't accept "your iron is fine" without seeing the actual ferritin number. If your ferritin is low, your doctor will likely recommend supplementation. Take iron with vitamin C to improve absorption, and avoid taking it with calcium, coffee, or tea. Increase dietary iron through red meat, chicken, fish, shellfish (haem iron, most absorbable), and lentils, spinach, pumpkin seeds, and fortified cereals (non-haem iron, paired with vitamin C-rich foods).

While your levels recover, support your scalp with professional products. A scalp-supportive shampoo and targeted serum help maintain follicle health during the recovery period.

"We always recommend a combined approach," says Samantha at Constantia. "Addressing the iron deficiency is the essential piece — but supporting the scalp with the right products at the same time means you're not losing ground while you wait for levels to improve."

06 — How Long Until Hair Grows Back

Once ferritin levels are restored, most people start seeing reduced shedding within 2 to 3 months. Visible regrowth typically takes 6 to 12 months. Patience is essential — and consistency with supplementation throughout the process matters. Don't stop supplementing as soon as you feel better.

Frequently Asked Questions

Can low iron cause hair loss without anaemia?

Yes — and this is very common. You can have low ferritin (stored iron) and experience significant hair shedding without being clinically anaemic. Always check ferritin specifically, not just haemoglobin.

How do I know if my hair loss is from iron deficiency?

The pattern is typically diffuse shedding across the whole scalp rather than patchy loss. A blood test showing low ferritin alongside hair shedding is a strong indicator. A trichologist can confirm with a scalp assessment.

What ferritin level should I aim for to stop hair loss?

Most hair loss specialists recommend a ferritin level of 70 to 80 μg/L or above for optimal hair growth. The standard lab "normal" range is often much lower and may not be sufficient for hair health.

How long does it take for iron supplements to stop hair loss?

Shedding typically starts to slow 2 to 3 months after ferritin levels begin to recover. Full hair regrowth can take 6 to 12 months. Consistent supplementation and dietary changes are key throughout this period.

Should I take iron supplements for hair loss without a blood test?

No — always confirm a deficiency with a blood test before supplementing with iron. Too much iron is harmful. Supplement only if you have a confirmed low ferritin level, under your doctor's guidance.

Book a scalp consultation at your nearest Partners Hair salon, or shop our professional hair growth range online. Free delivery on orders over R390.