What is ferritin?
Iron is the core of haemoglobin, the oxygen carrier in your red blood cells, and of the enzymes your muscles and brain use to make energy. What you do not need right away, your body puts away in ferritin, a protein that can hold thousands of iron atoms like a hollow ball. Most ferritin sits in your liver, spleen and bone marrow; a small part leaks into your blood, and that part moves with the size of the store. That is why the ferritin value is the measure of how much iron you have in stock, while your haemoglobin says how much you are using in your blood right now. Those two do not run in step. An iron deficiency starts with a store running empty, while haemoglobin stays up for months. In that phase you already have symptoms, tiredness, breathlessness on exertion, slower recovery, hair loss, while an ordinary blood count is still normal. Ferritin responds first, and that is why it is the value to know first when you are tired. The pitfall is that ferritin is also an inflammation protein. With an infection, an inflammation, liver damage or plenty of alcohol it rises independently of your store, and a normal value can then hide an empty warehouse. Your report shows ferritin in µg/L. Below 15 µg/L the store is empty, above 100 µg/L an iron deficiency is unlikely, and in between CRP and transferrin saturation decide.
Why is ferritin relevant?
Iron deficiency is one of the most common and most missed reasons for tiredness, especially in women who menstruate, in anyone who eats plant-based, in endurance athletes, pregnant women and blood donors. The symptoms are vague and creep in: less energy, out of breath sooner on the stairs, feeling cold, concentration slipping, hair thinning, restless legs at night. Because haemoglobin is still normal, it is often put down to being busy or sleeping badly. A ferritin value turns that suspicion into a number, and an empty store is cheap and easy to refill. For anyone who does sport, ferritin is even more interesting. Endurance sport uses iron: sweat, the impact of every footstrike that breaks red cells, and a gut that loses a little blood after a long effort. A ferritin that sits within the band but at the low end often goes together in athletes with less endurance, and many athletes feel better with a store above fifty. That is not a disease but a state of the store, and you adjust it with food and where needed a supplement. On the other side, a high ferritin is almost never iron overload. In practice it is more often inflammation, fatty liver, excess weight or alcohol: all reasons that lift the value without more iron being in stock, and that you bring down with lifestyle. The real iron overload, haemochromatosis, is an inherited condition in which the gut absorbs too much iron, and you recognise it by a high ferritin with a high transferrin saturation. That combination you do not want to miss, because it is very treatable as long as the organs have no damage yet.
Ferritin reference ranges
What counts beside the number:
- CRP from the same draw, because inflammation lifts ferritin and hides a deficiency
- Transferrin saturation: low in a deficiency, high in overload
- Haemoglobin and MCV, which show whether the deficiency is already working through into your blood
- How you menstruate, how you eat and how much you exercise
- In a man or a woman after the menopause: where the blood is going
- With a high value: your liver values, your waist and how much you drink
For ferritin the decision limits are more useful than your lab's band: below 15 µg/L the store is empty, above 100 µg/L an iron deficiency is unlikely, and in between CRP and transferrin saturation decide. The bands themselves run far apart per lab and with age and sex, because the store sits higher in men and after the menopause and rises with the years. With inflammation ferritin is falsely high and the limit for an empty store sits higher. Figures in µg/L equal ng/mL.
What Dutch labs actually use
30 – 120µg/L
Between 6 and 30 and between 120 and 175 it depends on the lab, because each sets its limits on its own method and population. Above 175 every lab calls it abnormal.
every lab calls 30 – 120 µg/L normal. Between 6 and 30 and between 120 and 175 it depends on the lab.
Every age, per lab
| Laboratory | Group | Reference range |
|---|---|---|
| Unilabs(Saltro, Medlon, SHO, Atalmedial)2026 | Men 15–20 yrs | 11–135 µg/L |
| Men 20–30 yrs | 19–200 µg/L | |
| Men 30–50 yrs | 19–305 µg/L | |
| Men 50–75 yrs | 15–460 µg/L | |
| Women 18–40 yrs | 6–120 µg/L | |
| Women 40–55 yrs | 6–180 µg/L | |
| Women 55–75 yrs | 9–250 µg/L | |
| Men 75+ | 19–460 µg/L | |
| Women 75+ | 11–350 µg/L | |
| Star-shl2026 | Men | 30–400 µg/L |
| Women | 15–150 µg/L | |
| Certe2026 | Men 18+ | 30–409 µg/L |
| Women 18–50 yrs | 30–175 µg/L | |
| Women 50+ | 30–328 µg/L | |
| Clinical Diagnostics2026 | Men | 25–250 µg/L |
| Women under 45 | 20–150 µg/L | |
| Women 45+ | 20–250 µg/L |
Each band as the lab publishes it, retrieved in 2026, unless marked otherwise.
Ferritin high or low: what it means
A low ferritin means an empty store, and the question is why. The most common explanation first: heavy periods, too little iron from food, a pregnancy, blood loss in the gut, endurance sport, and rarely poor absorption as in coeliac disease. In a woman who menstruates the explanation is usually clear. In a man or a woman after the menopause an iron deficiency rarely comes from food alone; the gut is then the first place the blood can go, and that is looked into before you start topping up. A high ferritin usually means inflammation or a liver under strain, not too much iron. Look at CRP and at your liver values and your waist: a high ferritin with a high CRP is an inflammation, a high ferritin with a high ALT and excess weight is fatty liver, and both fall away once the cause does. A high ferritin with a transferrin saturation above 45% is the picture of iron overload, and then investigation for haemochromatosis belongs with it. What you do about it: with an empty store you eat iron you absorb well, red meat, fish and poultry, and from plant sources legumes, whole grains and green vegetables with vitamin C alongside, because that doubles absorption. Tea and coffee block absorption, so not with the meal. If the store is really empty, food alone does not refill it fast enough and an iron tablet is the way; taking it every other day works better than every day, and count on three to six months before ferritin is back, because haemoglobin recovers before the store does. With a high ferritin without overload, less alcohol, less belly fat and tackling the inflammation are the levers. Read ferritin beside CRP, because inflammation hides a deficiency, and beside transferrin saturation, which is low in a deficiency and high in overload. Haemoglobin and MCV tell whether the deficiency is already working through into your blood.
What lowers it
The store is empty, and the question is where the iron went.
| Cause | How often |
|---|---|
| Heavy periodsThe most common reason in women before the menopause; every month more iron goes out than comes in with food | Often |
| Little iron from foodEspecially with plant-based eating, because iron from plants is absorbed far less well than iron from meat and fish | Often |
| PregnancyThe baby and the placenta draw iron from the store; at the end of a pregnancy it is often empty | Often |
| Blood loss in the gutOften goes unnoticed, from a stomach ulcer, haemorrhoids, a polyp or long-term painkillers; in men and after the menopause the first place to look | Sometimes |
| Endurance sportSweat, the impact of every footstrike and a gut that loses a little blood after long efforts; runners and cyclists often sit at the low end | Sometimes |
| Reduced absorption in the gutWith coeliac disease, after stomach surgery or with long-term antacids the iron does not get across the gut wall | Rare |
What raises it
Usually not iron overload, but ferritin rising with inflammation or a liver under strain.
| Cause | How often |
|---|---|
| Inflammation or infectionFerritin is an inflammation protein and rises with every infection or inflammation, independently of the store; CRP shows whether that is at play | Often |
| Fatty liverA liver full of fat leaks ferritin; it goes together with belly fat, a high ALT and insulin resistance, and falls with lifestyle | Often |
| Heavy drinkingAlcohol strains the liver and lifts ferritin; a few weeks without often lets the value fall already | Sometimes |
| HaemochromatosisInherited; the gut absorbs too much iron and it builds up in liver, heart and joints; recognisable by a high transferrin saturation beside it | Rare |
How does a ferritin blood test work?
- Referral
- Not needed. You can have ferritin measured yourself, and it is the most useful value for tiredness, for anyone who menstruates, eats plant-based or exercises a lot.
- Fasting
- Not needed; ferritin barely moves with food or the time of day. Skip an iron tablet on the day of the draw.
- When
- Not during or just after a cold, infection or operation, because ferritin is temporarily high then and says little about your store. Wait a few weeks.
- The draw
- One tube of blood from a vein in your arm. CRP, transferrin saturation and a blood count come from the same draw.
- Repeating
- Three months after starting iron to see whether the store is filling, and for anyone who menstruates or exercises a lot once a year.
- Which test
- Ferritin is in the Iron & fatigue test (€99) and in .
- Where to draw
- You can draw at 250+ locations near you, no referral needed. See the locations
Frequently asked questions
What is ferritin?
The protein your body stores iron in, mainly in your liver, spleen and bone marrow. A small part sits in your blood and moves with the size of that store, so the ferritin value is the measure of how much iron you have in stock. It does not say how much iron is circulating right now, transferrin saturation reads that, and it also rises with inflammation without your store growing.
What is a normal ferritin level?
Below 15 µg/L the store is empty, above 100 µg/L an iron deficiency is unlikely, and in between it depends on your CRP and your transferrin saturation. The labs' bands run far apart, roughly up to 150 for a woman and 250 for a man, because the store sits higher in men and after the menopause. Anyone who exercises or menstruates usually feels best with a store above fifty.
What does a low ferritin mean?
An empty iron store, almost always. In women that is usually the periods, beyond that too little iron from food, a pregnancy, endurance sport or blood loss in the gut. The symptoms come before there is anaemia: tiredness, breathless on the stairs, feeling cold, hair loss, restless legs. In a man or a woman after the menopause the gut is the first place to look, because that is usually where the deficiency comes from then.
What does a high ferritin mean?
Usually not too much iron. Ferritin rises with every inflammation or infection, with fatty liver, excess weight and alcohol, and those reasons are far more common in practice than iron overload. Look at CRP, your liver values and your waist. Only a high ferritin with a transferrin saturation above 45% points at iron overload, and then investigation for haemochromatosis belongs with it.
Why am I tired with a normal haemoglobin?
Because the store runs empty long before haemoglobin falls. Your body keeps the oxygen carrier in your blood up for as long as possible and empties the warehouse first. In those months you already have less energy, recover more slowly and get out of breath sooner, while an ordinary blood count is still normal. Ferritin responds first, and that is why it is the value to know first when you are tired.
How do I refill my iron store?
With iron you absorb well: red meat, fish and poultry, and from plants legumes, whole grains and green vegetables with vitamin C alongside, because that doubles absorption. Tea and coffee block absorption, so not with the meal. If the store is really empty, an iron tablet is the way; taking it every other day works better than every day. Count on three to six months before ferritin is back, because haemoglobin recovers before the store does.
What does inflammation have to do with ferritin?
Ferritin is also an inflammation protein. With an infection, an inflammation, liver damage or plenty of alcohol it rises independently of your store, and a normal value can then hide an empty warehouse. So have CRP measured alongside: if that is high, the limit for an empty store sits higher and transferrin saturation says more. Better to have blood drawn a few weeks after an infection than during it.
Do I need to fast for a ferritin test?
No. Ferritin barely moves with food or the time of day. What does count: not during or just after a cold, infection or operation, because the value is temporarily high then. Skip an iron tablet on the day of the draw, and have CRP and transferrin saturation come from the same draw.
Which tests include ferritin?
Ferritin is in the Iron & fatigue test (€99, also as an add-on for €15), in the comprehensive test (€229) and in .
Related biomarkers
Read on
Sources
- 1.NHG guideline on anaemia (M76), Dutch College of General Practitioners. 2024. richtlijnen.nhg.org
- 2.WHO, Guideline on use of ferritin concentrations to assess iron status. 2020. who.int
- 3.Unilabs, test catalogue (Dutch): ferritin. 2026. bepalingenklapper.nl
- 4.Star-shl, test catalogue (Dutch): ferritin. 2026. star-shl.nl
- 5.Certe, test catalogue (Dutch): ferritin. 2026. bepalingenwijzer.certe.nl
- 6.Clinical Diagnostics, lab guide (Dutch): ferritin. 2026. clinicaldiagnostics.nl
- 7.LESA Laboratory diagnostics (Dutch primary-care laboratory agreement). 2026. richtlijnen.nhg.org
Educational information only, not medical advice. Consult a healthcare professional for clinical decisions.
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