Menopause hair · Evidence led

Ferritin and hair loss: what a result can tell you

Iron stores are worth checking when hair sheds, but a single number is not a hair score. Here is what the evidence shows and what to ask your GP.

Lower ferritin, a measure of the body's iron stores, has been linked with some types of hair loss in women, though not every study agrees. A single number cannot diagnose why your hair is changing and it is not a target to chase on your own.

In clinic I often heard, "My friend said my ferritin should be over a certain number or my hair will not grow." That kind of rule sounds precise and it is not how clinicians use the test. This article explains what ferritin is, what the research shows and why guessing an iron dose is a bad idea. It is education to help you talk to your GP, not a set of results to interpret at home. For the wider list of causes, see hair thinning after 50.

Iron stores explained

Iron is used to make haemoglobin, the protein in red blood cells that carries oxygen. The NHS explains that if you do not have enough iron, you can develop iron deficiency anaemia, with symptoms such as tiredness and shortness of breath.^[2] Ferritin is one of the blood tests used to look at stored iron. A full blood count looks at the red cells themselves. Your GP interprets them together, not as isolated numbers.

Hair follicles are active tissues. When the body is short of iron, hair growth can be affected along with energy and other functions. That is the biological reason people connect ferritin and hair. It does not mean every woman with thinning hair is iron deficient, or that every lowish result is the full explanation.^[1]

Around perimenopause, periods can become heavier or closer together. Each heavy period is a chance to lose iron. A diet with little red meat, a vegetarian or vegan pattern without planned iron sources or problems absorbing iron (for example after some stomach operations) can add to the gap.^[2][5] Our article on perimenopause hair loss covers other changes that often arrive in the same years.

What the evidence shows

A frequently cited study compared women with hair loss with a control group and found lower ferritin in several hair loss types, especially shedding.^[3] A detailed review of iron deficiency and hair loss concluded that the relationship is plausible and that treating a proven deficiency is reasonable, while also stressing that evidence is not uniform.^[1]

A more recent systematic review and meta-analysis found that women with non-scarring hair loss had lower ferritin than women without it, while again noting variation between studies.^[4] In plain language: lower iron stores show up more often in women with certain kinds of hair loss, but a normal ferritin does not rule out pattern thinning and a low result does not prove it is the only cause.

Female pattern hair loss can occur with entirely normal blood tests.^[6][7] Telogen effluvium has many triggers besides iron, including illness, stress, thyroid change and medicines.^[8][9] That is why a result is interpreted beside your story, not instead of it.

Laboratory ranges are not targets

Every laboratory prints a reference range on the report. That range describes typical values in the population the lab serves. It is not a personal goal for thicker hair and it is not a number copied from a social media post.

Reviews of iron and hair loss have discussed different proposed cut-offs and have not produced a single agreed hair specific target.^[1][4] Two people with the same number can need different next steps, depending on symptoms, periods, diet, other blood tests and medical history.

If your result is flagged as low, your GP may look for the reason, not only hand you a supplement. Heavy periods, bowel symptoms or unexplained anaemia can need their own assessment.^[2] If your result is within range and your hair is still changing, that does not mean you imagined it. Pattern hair loss and midlife texture change often continue with normal iron.^[10][7][11]

Biotin, found in many hair and nail supplements, can distort some laboratory tests, including some heart tests.^[12][13] Always tell whoever takes your blood what you take. The lab or your clinician will say whether anything needs pausing.

When treatment is appropriate

If tests show iron deficiency or iron deficiency anaemia, your GP may recommend iron and will choose the preparation and duration for you. They should also consider why stores fell.^[2] Hair may take months to show a change after iron stores improve, because of the hair cycle.^[8][1] Some shedding continues for a while even after the trigger is treated.

Food first still matters. The NHS lists good sources of iron including lean red meat, beans, nuts, dried fruit, wholegrains and dark green leafy vegetables. Vitamin C rich foods help the body absorb iron from plants. Tea and coffee with meals can reduce absorption.^[2][5] Our nutrition guide for menopausal hair puts this in the context of protein and other nutrients.

Treating iron without a proven deficiency is not well supported as a hair strategy.^[1] Extra iron can cause constipation, stomach upset and, in people who absorb too much iron, real harm. Keep tablets away from children.

This page does not suggest a dose, a brand or a number to aim for. Those decisions are individual.

What to take to your GP

There is no universal hair panel. Depending on your history, your GP may consider a full blood count and ferritin, thyroid function and selected nutrient tests.^[14][15] Hormone tests are usually not needed to diagnose menopause in women aged 45 or over.^[15]

If you want a one page prompt before an appointment, start with our free 7 day hair kindness checklist, which includes writing down medicines and taking a baseline photo.

Keep your questions in one place

The Menopause Hair Guide includes a blood test conversation sheet, an observation tracker and a clear note on what tests can and cannot show. It will not interpret your results for you and it will not tell you to buy iron.

Keep reading

• Hair thinning after 50: causes worth checking
• Nutrition for menopausal hair: food first
• Perimenopause hair thinning: what to notice

This article is general education, not medical advice. It cannot diagnose or treat any condition. Speak to a qualified hair expert or your GP about hair changes and seek medical help promptly for the warning signs above.