Serum Iron Blood Test
Iron is an essential nutrient required for healthy red blood cell production and oxygen transport. A serum iron test measures the concentration of iron currently circulating in your bloodstream and is used alongside ferritin, transferrin and transferrin saturation to build a complete picture of your iron status. Both iron deficiency and iron excess can cause significant health problems, making this test a key part of preventive health screening.
Why Test Serum Iron?
A serum iron test is recommended if your diet is low in iron, meat or seafood, if you have symptoms such as fatigue, dizziness, rapid heart rate or insomnia, or if you have a personal or family history of anaemia or haemochromatosis. Heavy menstrual periods, pregnancy and athletic activity increase the risk of iron imbalance. Certain medications, including corticosteroids and antacids, can also affect iron levels.
What Do High Serum Iron Levels Mean?
The most common cause of high serum iron is hereditary haemochromatosis. Other causes include excessive iron supplementation, multiple blood transfusions, viral infections, liver disease and kidney disease. Symptoms may include fatigue, joint pain, abdominal pain, irregular heart rhythm, skin colour changes and, in severe cases, organ damage.
What Do Low Serum Iron Levels Mean?
Low serum iron is most commonly caused by iron deficiency anaemia, especially when paired with high transferrin and low transferrin saturation. Underlying causes include low dietary intake, low stomach acid, malabsorption, microscopic gastrointestinal bleeding and chronic disease. Symptoms include fatigue, pallor, dizziness and shortness of breath.
Symptoms to Watch For
- Fatigue and low energy
- Rapid heart rate
- Dizziness and lightheadedness
- Pale skin
- Shortness of breath
- Insomnia
- Joint pain (in iron overload)
Who Should Get Tested?
- People with diets low in iron, meat or seafood
- Women with heavy menstrual periods
- Pregnant women
- Athletes, especially endurance athletes
- Those with a personal or family history of anaemia or haemochromatosis
- People taking medications that affect iron absorption
- Anyone with unexplained fatigue or dizziness
How to Prepare for Your Test
Avoid iron supplements for 24 hours before the test. Take the test before 10 am, as iron levels fluctuate throughout the day. Note the day of your menstrual cycle if applicable. Bring valid ID.
Order Your Blood Test
Test your Serum Iron levels with an accredited Swedish laboratory. Results within days, reviewed by Wellth.
Frequently Asked Questions
Why should I test before 10 am?
What is the difference between serum iron and ferritin?
Can serum iron be interpreted alone?
Reviewed by
Wellth Team
Wellth
Our content is written and reviewed by Wellth, and fact-checked against peer-reviewed research and current Swedish clinical guidelines.
Learn more about our team →Medical Disclaimer
The information on this page is provided for informational purposes only and does not constitute professional medical advice, diagnosis, or treatment. Wellth provides health information and testing services but is not a substitute for clinical care. Always consult a qualified healthcare provider if you have questions about a medical condition. If you are experiencing severe or urgent symptoms, contact your doctor or call 1177 Vårdguiden. Blood test results should be interpreted by a qualified healthcare professional in the context of your complete medical history.