Ferritin is the protein that stores iron. Measuring it is the standard way to estimate how much iron your body has in reserve — low ferritin usually means depleted stores, often before anaemia shows up on a blood count.
Check your value
Reference range used: 40–150 ng/mL. Runs in your browser — nothing is stored.
ng/mL
—
Wellness information, not medical advice. Reference ranges vary between laboratories and depend on age, sex and context. This page cannot diagnose anything — always read your result with the range printed on your own report, and discuss concerns with a doctor.
It has one important quirk: ferritin is also an acute-phase reactant. Infection, inflammation, liver conditions and heavy alcohol use all raise it, which can mask a genuine iron deficiency behind a normal-looking number.
Why it matters
Iron sits at the centre of oxygen transport and energy production. Both ends of the range matter — too little causes fatigue and poor exercise tolerance, while persistently high levels warrant investigation.
What influences your ferritin
Menstruation and pregnancy, the most common reasons for low ferritin in women.
Dietary iron and absorption — plant-based iron is absorbed less efficiently, and coffee or tea with meals reduces uptake further.
Inflammation or recent infection, which pushes ferritin up independently of iron stores.
Blood donation, which can lower ferritin substantially for months.
What to do with the result
If ferritin is low, the useful question is why — the cause matters more than the number, and unexplained iron deficiency should always be investigated by a doctor.
Read ferritin next to a marker of inflammation such as CRP. Normal ferritin with high CRP can still mean depleted iron.
Do not start iron supplements based on this number alone — excess iron is harmful and supplementation should be guided by a doctor.
Common questions
What is a normal ferritin level?
Laboratory ranges vary widely, but roughly 30–300 ng/mL for men and 15–200 ng/mL for women is typical. Many clinicians consider values under 30 ng/mL as indicating low iron stores even when the lab flags them as normal.
Why are men's and women's ranges so different?
Menstrual blood loss lowers iron stores in women of reproductive age. After menopause, women's ferritin typically rises towards the male range.
Can ferritin be high without excess iron?
Yes, and this is common. Inflammation, infection, liver disease, obesity and alcohol all raise ferritin. A high result on its own does not mean iron overload — transferrin saturation helps distinguish them.
How long does it take to correct low ferritin?
Rebuilding iron stores typically takes 3 to 6 months of consistent intake, sometimes longer. It is slow by nature.
See this marker in context
A single value tells you little on its own. PhisBio Lab reads your whole blood panel and shows how five body systems — including Metabolism — are doing together.