About haemoglobin, iron and ferritin
Haemoglobin is a protein that carries oxygen from the lungs to the rest of the body.
Our bodies need iron (an important mineral found in the foods we eat) to make haemoglobin, and for our general health and wellbeing.
Ferritin is the protein that stores iron, so ferritin testing is how we measure iron stores.
When you donate blood you donate your red blood cells, which contain haemoglobin. This causes a drop in your haemoglobin.
That’s why we test your haemoglobin before each donation — we want to make sure it’s at a safe level for you to donate.
After you donate your body uses its iron stores to replenish your haemoglobin and red cells. Your body will be more efficient at replacing these if you have healthy iron stores. The iron stores that you use will then be replaced through your diet over time.
It’s important to maintain healthy iron stores as low iron (even with a normal haemoglobin) can lead to fatigue, impaired concentration or difficulty exercising. Low iron may also lead to low haemoglobin (anaemia), which may cause breathlessness and dizziness.
We recommend a healthy, iron-rich diet. The time it takes to replace the iron you have used to replenish your red cells after a donation varies from person to person. For some people, it takes longer than the 12-week minimum break we allow between blood donations. It generally takes longer for people who have higher iron requirements (e.g. younger donors or female donors) or low dietary iron intake (e.g. vegans and vegetarians).
We check your haemoglobin in the donor centre before each donation. This is usually with a fingerprick test, but in some of our centres we do it using a small sample of blood taken from the donation needle. Your haemoglobin will need to be in our acceptable range to donate.
Acceptable haemoglobin ranges
|Female donors||Male donors|
|Blood 120–165 g/L||Blood 130–185g/L|
|Plasma/platelets* 115–165g/L||Plasma/platelets* 125–185g/L|
* The minimum range is lower for plasma and platelets because you get most of your red blood cells back during the donation. Find out more about donating plasma.
Do you test my iron level?
Some people think that the screening fingerprick test we do checks your iron, but it actually only measures haemoglobin. Haemoglobin and iron are linked, but the haemoglobin test can’t tell us what your iron levels are. Some people can have normal haemoglobin levels at the same time as having low iron levels.
Ferritin is the test used to measure iron stores. We can’t check your iron stores before you donate as it’s a test that needs to be done on your blood sample in a lab.
Lifeblood has offered ferritin testing in very specific cases before, but we are now going to be testing more donors.
What's the best way to reduce the effect of donating on my iron stores?
- If you donate blood, we recommend a healthy iron-enriched diet.
- Women aged 18-45 are particularly susceptible to low iron because of menstruation and pregnancy so we recommend a short course of iron supplements each time after you give blood (but not plasma). We understand iron supplements are not appropriate for everyone so please read our brochure carefully and talk with your GP or pharmacist. For other donors we recommend you speak with your doctor to see if iron supplements are suitable for you.
- Although you can give blood every 12 weeks, this may not be suitable for everyone, especially for our younger donors, women of child-bearing age, or donors who have had low haemoglobin and or iron in the past. If that’s true for you, consider donating less often or give plasma, which has a very small impact on iron.
- If you’re planning for pregnancy, it’s especially important that you build and maintain healthy iron stores. Talk to your doctor about how best to manage your iron health in this situation.
Taking iron supplements
If you’re a female donor aged 18-45 and donating blood, we recommend that you take a short course of iron supplements after your donation.
Download our iron recommendations below for information on replacing your iron. Please read the flyer in full before buying any iron supplements and see your doctor if you have any concerns or questions.
- You’ve recommended iron supplements to me. Can I use a multivitamin instead?
While a lot of multivitamins do contain iron, most only have a small dose of elemental iron (e.g. 5mg per tablet). Multivitamins wouldn’t replace the iron you donated as quickly as one of the supplements we recommend.
If you’d prefer to use a lower dose iron supplement, speak with your pharmacist.
- Why do I have to tell the pharmacist if I’m taking medications?
Iron supplements can interact with some medicines when taken at the same time. The iron may change the effectiveness of your medication, or your medication may affect how your body absorbs the iron.
Your pharmacist can let you know if you need to take your iron supplement at a different time of day to your medicine.
- Why do I have to tell the pharmacist if I’m taking other supplements?
Many supplements already contain iron, including those for pre-pregnancy. Your pharmacist can let you know how much iron, if any, is in your current supplement and help you decide if you need more to help replace what you’ve given during donation.
If you’re taking a pre-pregnancy supplement, you should continue taking it — it also contains folate.
- Why isn’t Lifeblood providing or paying for the supplements?
Australian legislation doesn’t allow us to provide iron to donors. Only pharmacies can dispense these supplements.
- Why don’t you recommend taking iron supplements after a plasma donation?
When you give plasma, your red cells are returned to you. That means you don't give as much iron in your donation, and our research shows that plasma donors usually aren’t at an increased risk of low iron.
If I don’t menstruate and haven’t been pregnant recently, do I still need to take the iron?
We’re recommending iron for all women aged 18-45 regardless of menstrual or pregnancy history. Speak with your doctor if you’re not sure about your iron requirements.
- If I take iron can I donate blood more often?
No. For your health and wellbeing, you still need to wait 12 weeks between blood donations. It’s a different story for plasma, though! Learn more about giving plasma.
- My haemoglobin is normal, do I still need to take iron?
After donating, your body uses iron to make haemoglobin for new red cells. Your body will absorb the iron it needs from diet, but it can take months to get back to the level it was. A short course of iron supplements can help you maintain healthy iron levels, keeping you feeling your absolute best.
- You tested my ferritin and the result was normal. Do I still need to take the iron supplements as recommended?
Yes, we recommend that you do. The ferritin testing we did was on blood taken just before your donation, and donating blood can lower your ferritin, so it will generally be lower after your donation than the test results indicate. The course of iron will help you replace the iron you are now using up to replace your haemoglobin and red cells.
- Should I donate blood if I can’t, or choose not to, take iron supplements?
It’s really up to you, but it’s important that you consider your own health and wellbeing. Have a think about reducing how often you donate or try giving plasma instead, which has a smaller iron loss and bonus – when it comes to donating, it’s a game-changer.