Vitamins & iron · Blood test
Serum iron blood test: normal range explained
Also printed as: Iron, Iron Serum, S. Iron, Fe
Serum iron is the amount of iron travelling in your blood at the time of the test. The adult range commonly printed on Indian reports is 60–170 µg/dL; Testing.com prints 50–180 µg/dL for men 30 and over, MedlinePlus 59–158 for men and 37–145 for women, and the range printed on your own report is the one that applies.
Last updated 3 sources
What is the normal range for serum iron?
| Printed for | Range |
|---|---|
| Adults | 60–170µg/dL |
| Men, as MedlinePlus prints it | 59–158µg/dL |
| Women, as MedlinePlus prints it | 37–145µg/dL |
| Men, in µmol/L, as MedlinePlus prints it | 10.6–28.3µmol/L |
Reference ranges vary between laboratories. Always use the range printed on your own report. Why ranges differ between labs
Sources:Testing.com, MedlinePlus
What does serum iron measure?
Serum iron measures the amount of iron in your blood, most of it bound to transferrin, the protein that moves iron through the body. It does not measure stored iron; that is ferritin. The two are usually ordered together with TIBC (total iron-binding capacity) and transferrin saturation.
Reports print serum iron in µg/dL (also written mcg/dL) or µmol/L. MedlinePlus prints both: 59–158 µg/dL is 10.6–28.3 µmol/L for men.
Sources:MedlinePlus, Testing.com
Why do doctors order the serum iron test?
Doctors order iron tests most often to check for low iron, a cause of anaemia, and to tell apart types of anaemia. MedlinePlus lists tiredness, dizziness, shortness of breath and an irregular heartbeat as symptoms of low iron, and joint pain, abdominal pain and skin colour changes as symptoms of too much.
Serum iron is also used to look for iron overload (haemochromatosis), to check liver iron stores, and to follow treatment. Testing.com says a single out-of-range result is not a diagnosis, and that serum iron fluctuates, which is why it is read with ferritin, TIBC and transferrin saturation.
Sources:MedlinePlus, Testing.com
What can change your serum iron result?
Serum iron changes through the day and with what you ate, more than most blood values.
- Time of day: iron is usually highest in the morning and falls through the day, so labs often ask for a morning sample.
- A recent meal or an iron supplement pushes the result up; Testing.com says to stop iron supplements at least 24 hours before, if your doctor agrees.
- Birth control pills and oestrogen treatments can affect iron levels, as can some antibiotics, blood pressure and cholesterol medicines, deferoxamine, gout medicines and testosterone.
- Menstruation lowers iron for many women during their cycle, and pregnancy is a listed cause of a low result.
- Inflammation can lower serum iron while ferritin stays normal or high.
- Vitamin C raises iron absorption, while antacids and proton pump inhibitors lower it; do not stop any medicine before talking to your doctor.
Sources:MedlinePlus, Testing.com
How do you read serum iron on your lab report?
Reports print Iron, Serum Iron or S. Iron in µg/dL, usually beside TIBC, transferrin saturation (%) and ferritin on an iron profile. MedlinePlus prints separate ranges for men and women, and Testing.com prints ranges by age as well, so read your value against the range on your own report.
Because serum iron rises and falls within a day, two reports taken at different times can differ without any real change. Your doctor reads it with ferritin and TIBC: Testing.com says low ferritin with high TIBC suggests iron deficiency, while normal or high ferritin with low serum iron may point to inflammation.
Amara reads serum iron with the range printed beside it on each report, flags a value outside that range, and shows what changed since your last report. Try it with two sample reports
A sample Amara row for Serum Iron: 57 µg/dL on 18 Nov 2025 at Lab A (sample), then 92 µg/dL on 9 Jun 2026 at Lab B (sample), each with its lab's printed range.
Sources:MedlinePlus, Testing.com
Questions people ask about serum iron
Why is serum iron read with ferritin?
Serum iron shows the iron in transit at one moment, and ferritin shows the iron in store, so doctors read the two together. Testing.com says serum iron fluctuates and that a normal haemoglobin can sit beside empty stores, while MedlinePlus lists ferritin, transferrin and TIBC as the tests that complete the picture.
Do I need to fast for a serum iron test?
Fasting is usually asked for before an iron test. MedlinePlus says your provider may ask you not to eat or drink for 12 hours and to have the sample taken in the morning, and Testing.com says the same, adding that water is fine. Iron supplements are usually paused beforehand, but only if your doctor says so.
What is the difference between serum iron and TIBC?
Serum iron is the amount of iron in the blood; TIBC (total iron-binding capacity) is how much iron the blood's transferrin could carry if full. Transferrin saturation, a percentage, shows how much of that capacity is in use. Testing.com says serum iron is read with ferritin, TIBC and transferrin saturation, and MedlinePlus lists them among the iron tests.
What does a low serum iron on my report mean?
Low serum iron means the value is below the range your lab printed. MedlinePlus lists long-term bleeding in the digestive tract, heavy periods, poor absorption, too little iron in the diet and pregnancy among the reasons, and a sample taken later in the day reads lower. Your doctor reads it with ferritin, TIBC and haemoglobin.
Sources:MedlinePlus, Testing.com
Sources
- Iron TestsMedlinePlus · medlineplus.gov · Opened
- Serum iron testMedlinePlus · medlineplus.gov · Opened
- Iron Blood Test: Check Your Levels, Learn What They MeanTesting.com · testing.com · Opened
About this page
Every statement on this page comes from the sources listed above. Ranges are those commonly printed on Indian lab reports; the range printed on your own report is the one that applies.
Published by Amara Health, a product of MetaNova AI Private Limited, Hyderabad.
Amara Health does not provide medical advice, diagnosis or treatment. Information shown by Amara is based on available health records and may contain errors. Review important information against the original report and consult a qualified healthcare professional for medical decisions. Do not use Amara for medical emergencies.
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