The body draws down stored iron long before haemoglobin falls. By the time anaemia appears, stores have been empty for some time. Ferritin measures those stores, and a low ferritin with a normal haemoglobin explains a great deal of unexplained fatigue and hair fall.
Three stages, one test that catches the first
Iron depletion proceeds in stages. First, stored iron falls while everything else holds steady. Second, iron available for making red cells falls, but haemoglobin is maintained. Third and last, haemoglobin falls and anaemia is diagnosed.
A haemoglobin test only finds the third stage. Ferritin finds the first. Since iron is needed for far more than red cells — energy production in every cell, thyroid hormone synthesis, hair follicle function — symptoms often appear a long way before anaemia does.
Is this what is happening to you?The two-minute check further down asks four questions and shows the result immediately. No email, no call.
Take the 2-minute checkWhat low iron feels like before it is anaemia
These are commonly attributed to stress, age or overwork, which is why the deficiency runs on for years.
- Fatigue that sleep does not resolve
- Breathlessness on stairs that used to be manageable
- Diffuse hair fall, often noticed while washing
- Difficulty concentrating, and a shorter fuse than usual
- Restless legs at night
- Brittle nails, and cracks at the corners of the mouth
2-minute check
Why are you so tired?
Four questions. Fatigue nearly always has a findable cause.
How much do you sleep, and how well?
Any hair fall, breathlessness on stairs, or heavy periods?
Do you crash in the afternoon?
Any low mood or difficulty concentrating?
No obvious driver from these answers
If it persists, thyroid, ferritin and vitamin D are the sensible first tests.
There are likely contributors here
Ferritin, thyroid and vitamin D between them explain most persistent fatigue.
Several contributors appear to be present
This is worth testing properly rather than pushing through. All three common causes are treatable.
This check is an indication, not a diagnosis. It does not replace medical advice.
Who is most likely to be low
Menstruating women, particularly with heavy periods, are the largest group. Pregnancy raises requirement substantially. Vegetarian diets supply iron in the less-absorbable plant form. Frequent blood donors, endurance athletes and anyone on long-term acid-suppressing medication are all at raised risk, the last because stomach acid is needed for absorption.
In India, the background prevalence in women of reproductive age is high enough that a low result should be considered likely rather than surprising.
Correcting it
Food matters and food is slow. Where stores are significantly depleted, diet alone often cannot refill them at a useful rate, and supplementation is a medical decision — iron supplements are not harmless, and taking them without a confirmed deficiency can cause harm.
What food does well is absorption. Vitamin C alongside plant iron increases uptake substantially. Moving tea and coffee an hour away from meals removes one of the largest blockers in the Indian diet. Separating calcium supplements from iron-rich meals helps, since the two compete.
And the question behind the question always deserves an answer: iron deficiency in an adult man, or in a woman past menopause, needs its cause investigated rather than simply corrected.
In short
Questions we are asked
What ferritin level is adequate?
Laboratory ranges commonly start around 12–15, and many clinicians consider levels in that region insufficient for symptom resolution, particularly for hair. Interpret it with your doctor, alongside your symptoms.
Can I just take an iron supplement?
Not without testing. Iron supplements cause digestive side effects and are genuinely harmful in conditions such as haemochromatosis. Confirm the deficiency first.
Reading about it is the easy part.The assessment turns this into your own numbers — free, with a free first consultation, and no figure quoted that we cannot substantiate.
Start my free assessmentConditions this relates to
Recipes that put this into practice
Palak and lemon dal
The lemon at the end is not a garnish. It is what makes the iron usable.
See the recipe →Overnight soaked figs and prunes
The most reliable thing we recommend for constipation, and the one instruction people skip.
See the recipe →Selenium and zinc seed mix
A spoon a day for thyroid and immune support — and why two Brazil nuts is the limit.
See the recipe →Related reading
Why weight will not move when your thyroid is underactive
When effort stops producing a result, the problem is often not the effort.
Read →What actually changes in a PCOS diet
Not a list of forbidden foods — a set of changes to how meals are built.
Read →Eight numbers worth understanding on your blood report
Most reports get read for what is flagged. The useful information is often elsewhere.
Read →References
- World Health Organization — guideline on use of ferritin concentrations to assess iron status.
- Ministry of Health and Family Welfare, Government of India — Anaemia Mukt Bharat operational guidelines.
- [Further references to be completed by the medical review panel.]
This article is general health information, written by a clinical nutritionist and reviewed by a doctor. It is not a diagnosis and it does not replace advice from your own clinician. Never change prescribed medication on the basis of what you read here.