Iron Tests – Understanding Your Blood Test Results

In this episode of the “Understanding Your Blood Tests Results” series, Dr Sandra Cabot and naturopath Margaret Jasinska delve into iron studies testing and what they mean. They explain how the reference ranges are small and ideally your iron stores (ferritin) will ideally be much higher. They look at the causes of low iron, such as heavy menstrual bleeding and how to boost your iron levels.

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DR CABOT: Hi. My name is Dr Sandra Cabot. And today Margaret Jasinska and myself are talking to you about how to interpret blood tests that are looking at your iron status. Now it’s pretty routine to have an iron test done. And this is usually done every twelve months, particularly in people who are tired. And it’s a very important test, isn’t it, Margaret?

MARGARET: Yes, absolutely! Because iron deficiency is so common, particularly in women. And fatigue is such a common problem or symptom. Nearly every patient that comes to see us, fatigue is one of their problems. And I like fixing easy problems. And if iron deficiency is a cause of your fatigue, we can do something about it.

DR CABOT: Yeah. Why is it important to know how much iron is in your body? Well, iron is a mineral and it is found in the body, in just about every cell. But it’s particularly important for the manufacture of red blood cells. So, inside a red blood cell, iron is attached to a protein called globin. And so, this product is known as hemoglobin. And when we do a full blood count and we measure the amount of red blood cells and white cells, we also measure the amount of hemoglobin that’s in your blood. So, this hemoglobin is the protein and the iron that is found inside the red blood cells. And the hemoglobin is critical to your health because that is what carries oxygen.

So, hemoglobin is traveling around your whole body in your red blood cells and being carried to every cell in your body to deliver oxygen to your cells. And we know your heart and your brain and your liver have a very high requirement for oxygen. So, it’s vitally important that you have enough hemoglobin to deliver that oxygen. Otherwise, all the metabolic processes inside your cells will slow down and you can have very severe health outcomes from that – widespread symptoms.

So, this is why every year most doctors will check a full blood count, looking at your hemoglobin. And if it is a little bit low, they’ll often do, what we call, serum iron studies, where we look at a total profile to evaluate, well how is iron being used in your body?

MARGARET: Yes. So, the blood test called iron studies, is the most thorough blood test to check your iron level.

DR CABOT: It is. And what do we look at? Well, first of all, we look at how much iron is in your blood – just floating around in the serum in your bloodstream. And the normal range is quite wide. It’s generally considered anywhere from 5 to 30 umol/L. So, 5 to 30. Well, you don’t want to be 5, obviously. You don’t really want to be 6 or 7. Ideally, you want to be somewhere around 15 to 20. And we see so many people with low serum iron, particularly women who have heavy menstrual bleeding. And we’ll look at some of the causes of iron deficiency in a minute.

So, the serum iron is the first thing we check. How much iron is floating around in your blood. That’s free iron. It’s free to do its action.

The other thing we look at is the amount of protein in your blood that is dedicated to carrying the iron around your bloodstream. And that is called transferrin. That’s a protein that’s made by the liver and that is dedicated to carrying iron around your body to deliver it to your bone marrow or your liver or wherever else it will be needed. And the normal range of transferrin is 2 to 3.6. So, that gives us more of an overall picture.

And then we look at, well how much of the transferrin is carrying the iron. In other words, how saturated is that transferrin with iron? And that ranges 10 to 45. So, it’s getting a bit complicated, but obviously it’s good to be in the middle of the normal range. About 20% to 30% is good. We obviously want the transferrin protein to have enough iron on it, to have enough saturation.

Now, the other thing that’s very important when we check your serum iron studies or do a serum iron profile (same thing), is to look at something called ferritin. Now, ferritin really reflects the total amount of iron in your body, in your whole body. So, it’s a storage-form of iron. And the normal range is really quite wide. And that’s why it can be hard to interpret. And the range is 15 to 200 ug/L. Well, that’s a wide normal range, isn’t it? 15 to 200. So, ideally you want to be somewhere in the middle, right? About 100. That would be great because that means your body is storing enough iron.

MARGARET: Usually, my female patients are towards the bottom. My male patients are towards the top.

DR CABOT: Men are from Mars and women are from Venus. Now that’s because women are often iron deficient because of the heavy menstrual periods. And they put up with it for years and years and years. And the doctor says, “Well, take an iron supplement.” Sure, take an iron supplement. Very important. Eat more red meat. Very important. But also treat the problem. Use some hormonal balancing to stop the heavy menstrual bleeding. And we discuss that in my books “Don’t Let Your Hormones Ruin Your Life” and the other book “How Not To Kill Your Husband”, that talks about progesterone and how it can reduce heavy menstrual bleeding. And if it persists, see a good gynecologist, because nobody wants to live their life with chronic iron deficiency.

MARGARET: Yes, that’s right. And apart from heavy menstrual bleeding, other things that can make the iron level low, particularly low ferritin, you could be losing blood from somewhere else in your body. You could be losing it from your intestines. There could be a bowel polyp. So, particularly in older people and particularly in men or women that don’t menstruate anymore, if iron levels are low, then there will often be some kind of gastrointestinal investigation to check if iron’s being lost from somewhere else. But also, you might not be losing it. You might be eating it, but you might not be absorbing it because of a gut problem.

DR CABOT: That’s correct. For example, you might have non celiac gluten intolerance, which is damaging your gut. And you may not realize that your small intestine is not doing a good job of absorbing the iron. Or you may have parasites in your stomach or small intestine that is stealing your iron. And this is not an uncommon symptom of parasite infection, isn’t it?

MARGARET: Yes. And also, just actual celiac disease, too. Or inflammatory bowel disease. Small intestinal bacterial overgrowth. A number of different gut problems can cause malabsorption of iron. And a lot of people are recommended an iron supplement, but they don’t take it because it makes them feel unwell. It makes them constipated, or it gives them abdominal discomfort. So, there are good and not good types of iron supplements. So, there are some that are more gentle on your gut and well absorbed.

DR CABOT: Yes. I often recommend something called Spatone, which is Australian made. It’s a liquid. You need to mix it with some type of citrus juice or tomato juice, because it does have a bit of a taste, like a rusty fence. But it works! And then there’s another one called Maltofer, which some people find well tolerated. And then you look at your diet because you may not be getting enough iron in your diet.

MARGARET: Yes. Because if you’re not eating iron or you’re not getting it from supplements, then you’re just not going to be getting enough. And so, animal foods are the highest foods in iron. So, red meat, in particular. Liver. The liver is where humans and most animals store the majority of their iron. So, eating somebody else’s liver will give you iron. And also, other animal foods like seafood, poultry, eggs. All of those foods do contain some iron. On paper, vegetables like spinach or nuts or legumes contain iron. But the human body can’t really absorb or utilize that iron. And we can prove that. Often, people will have gone to a dietitian or their own GP will say, “Just eat more spinach. Just eat more lentils.” And they’ve been doing that for some time. They have repeat blood tests, but it hasn’t worked.

DR CABOT: That’s right. Eating red meat is the best way to get iron. But if that’s against your philosophy, well, you need a good iron supplement. Or try and eat eggs, because organic eggs are really a good source of iron. But a lot of people don’t really understand why they feel so bad when they’re iron deficient. They think, “Well, it’s just because I’m a bit anemic.” But it’s really because you’re not carrying enough oxygen to the cells in your body.

MARGARET: Yes. And you will have a reduced exercise capacity, if you are iron deficient. So, you’ll feel tired and out of breath and feel unfit and not be able to make progress with your exercise, if you’re iron deficient. And there are studies that show that iron deficiency makes it harder to lose weight and worsens metabolic syndrome or Syndrome X or insulin resistance. And when I tell people that, it’s motivating to them.

DR CABOT: To take their iron supplements.

MARGARET: Absolutely! Because most women – new patients that come to see me – they know they’re iron deficient. They’ve been iron deficient for years, but it’s not rectified. Well, tell them that their iron deficiency is causing them to not be able to lose weight and to lose scalp hair, and then they’re motivated to fix the iron.

DR CABOT: And the other unpleasant symptom is you feel dizzy. You’re not getting enough oxygen to the brain. Remember, the iron is carrying the oxygen to every cell in your body. So, your brain is not going to work properly.

MARGARET: Exactly. Well, if you’re a student, if you have a job that requires you to use your brain a lot, your life will be harder if you’re iron deficient.

DR CABOT: Absolutely.

MARGARET: In children, their IQ, their learning ability is compromised if they’re iron deficient.

DR CABOT: That’s right. And people put up with it for years. So many women put up with chronic iron deficiency. We do iron infusions in our clinic with something called ferinject. You get 1000 milligrams of iron. Bang! And within 24 hours, people go, “Wow, I feel completely different!” Because they’re getting the oxygen delivered to their cells.

So, a lot of people can have quite severe iron deficiency, but it doesn’t show up as significant anemia in their blood. So, they still have red blood cell levels within the normal range. But the hemoglobin will tend to be at the lower limit. But if the serum iron profile is not ordered and you don’t get a complete picture of all the parameters which reflect your iron metabolism, well, then you can remain undiagnosed and you can keep feeling very, very tired and really way below your normal ability for years, unless it’s rectified.

So, make sure you have a serum iron profile. We’re looking at your serum iron, your saturation, your transferrin and your ferritin. And ferritin is a really good thing. Ferritin is how much total iron is stored in your body. So, I often make an analogy, your ferritin is like how much money you got in the bank, in your savings account. Whereas, your serum iron is how much cash you got in your pocket. So, you might have reasonable serum iron. So, you’ve got a bit of cash, but it won’t last very long because your ferritin is way low. So, you don’t have any cash reserves saved there. So that’s why we need to look at all those four parameters.

MARGARET: Yes. And sometimes on a blood test, we see ferritin abnormally high.


MARGARET: So, what kind of things can cause that?

DR CABOT: Well, if the ferritin is abnormally high, but the other iron parameters are normal, that is a marker of inflammation in your body, which is causing cell damage. It could be liver inflammation. It could just be the inflammation of chronic infection or some other chronic disease, which is causing cell damage and putting your ferritin up. But if the other iron parameters, namely your serum iron and saturation and transferrin, are normal then it’s not hemochromatosis. Because people always think, “If I got too much iron, I got hemochromatosis”, which is a recessive gene and it’s a very serious genetic disease and it’s treated by removing your blood. And sometimes people with high ferritin will be wrongly diagnosed as having hemochromatosis because their serum iron isn’t understood. So, if your serum iron is normal and your saturation is normal but your ferritin is high, it’s not hemochromatosis. It’s not a genetic problem. It’s an inflammatory problem. You’ve got something hiding there that needs to be investigated.

MARGARET: I saw a patient earlier this week who had a fatty liver for a couple of years. Already her normal ferritin level was 100 and something. She had a knee replacement and she was in a lot of pain afterwards. And she took strong painkillers for quite some time and she did a lot of comfort eating. She got a bit depressed. She didn’t get any movement and she wasn’t looking after herself. And then she had another blood test and her liver enzymes became very, very elevated. And her ferritin jumped to 1300. But then a few months after that, her knee recovered. She got back on track again with her health. Her liver enzymes are still elevated, but nowhere near the levels they had been. And her ferritin went back down to 100 and something again. It was just temporarily elevated.

DR CABOT: Correct. Yeah. It reflects inflammation. And similarly, in a patient with a bad fatty liver or someone who’s a really heavy drinker, they may have very high ferritin – over 1000. And remember, the normal range is up to 200. And that is reflecting liver damage, so, damage to the liver cells. And when that person changes their diet and lifestyle and stops drinking, the ferritin comes back to normal. But the whole time their serum iron has been normal, so they don’t have hemochromatosis.

So, it is a bit tricky analyzing these things. But the main thing is, have a full serum iron profile or serum iron studies done.

MARGARET: Yes. And if you listen to this podcast, while looking at your blood test result – having the result in front of you – this will make a whole lot more sense to you. Because you can follow along to the various terms that we’ve used, like transferrin, ferritin. You’d be able to see that on your test result.

DR CABOT: Yes. So, the serum iron is like the amount of cash you got in your pocket. That’s not going to last too long because you need iron every day. And the ferritin is how many iron molecules are stored in your body. So that’s your savings in your credit account. And that’s very, very important because that’s what’s going to last you.

So yeah, it’s interesting and iron is the stuff of life. It carries our oxygen so it’s good to know what yours is.

MARGARET: Thanks for listening everybody.

DR CABOT: And you can always send us an email, of course. We’re happy to answer you. We love to hear from you. And we hope you enjoy this podcast.

MARGARET: Bye bye!