You Can Have Too Much Iron In Your Diet

Many people are aware that low levels of iron in their body can lead to anaemia, with symptoms such as fatigue. But few realise that too much iron can result in a potentially fatal condition.

Meat picture from Shutterstock

Normally, if we have enough iron in our body, then no further iron is absorbed from the diet, and our iron levels remain relatively constant.

But the body also has no way of excreting excess iron. In a condition called hereditary haemochromatosis, the most common cause of iron overload, the mechanism to detect sufficient iron in the body is impaired and people can go on absorbing iron beyond the normal required amount.

Untreated, haemochromatosis can result in scarring to the liver (cirrhosis), liver cancer, damage to the heart and diabetes. These problems are the result of excess iron being deposited in the liver, heart and pancreas. Haemochromatosis can also cause non-specific symptoms such as fatigue, loss of libido and arthritis. In some, it results in a shortened lifespan.

The most common cause of hereditary haemochromatosis is a mutation received from both parents, in a gene called HFE.

Around one in every 200 Australians of European heritage have a double dose of this gene fault and are at risk of developing the disorder. Haemochromatosis is much less common among people who aren't of European ancestry.

Approximately 80 per cent of men and 60 per cent of women who have inherited this gene fault from both parents develop high iron levels. And of those who do, up to 40 per cent of men and 10 per cent of women will develop health problems.

Diagnosis

Actual blood iron levels are generally normal in those with haemochromatosis, as excess iron in the body is stored in tissues like the liver. So haemochromatosis is diagnosed by testing blood iron indices called transferrin saturation and serum ferritin levels.

Transferrin is a protein that transports iron around the body; ferritin is a protein that stores iron. The more iron in the body, the more ferritin that is made. Those with the haemochromatosis generally have high transferrin saturation and serum ferritin levels.

These proteins are very important in minimising tissue damage from iron, as iron that is not stored in ferritin or bound to transferrin is very toxic to cells.

If abnormal iron indices are identified, then genetic testing is usually the next step. Sometimes a liver biopsy is also required, to assess the degree of excess iron and whether there is permanent scarring of the liver.

There is debate among experts over whether everybody should undergo genetic testing for the disorder, even if they don't display symptoms.

Those who argue for blanket screening claim that if a person is at risk, knowledge of their condition will allow them to have their ferritin levels monitored, and they can seek treatment to prevent severe problems.

Arguments against the practice include the high cost of genetic screening, and the fact that many people who have the genetic risk don't go on to develop the disorder.

Treatment

Donating blood is the primary form of treatment for haemochromitosis. Red blood cells contain haemoglobin, which is very high in iron – removing red blood cells therefore removes iron.

While there's no doubt that people with very high iron levels due to haemochromatosis require treatment through donating blood, the evidence is less clear for those with only slightly elevated iron levels.

A research study call Mi-iron is underway in Melbourne, Brisbane and Perth to examine whether there are benefits to treatment when there is only moderate iron excess.

In this study, individuals will either have their iron levels normalised or left untreated without the person knowing which is the case (there's more information here about how this is achieved). Various symptoms are being assessed before and after the intervention to see if people with haemochromatosis who don't have severely elevated iron levels benefit from treatment.

Media campaigns may encourage us to eat more red meat, in part to make sure that we get enough iron. But with haemochromatosis, there can be too much of a good thing.

Martin Delatycki is the director of the Bruce Lefroy Centre for Genetic Health Research at Murdoch Childrens Research Institute. He receives funding from National Health and Medical Research Council, Friedreich Ataxia Research Alliance, Friedreich Ataxia Research Association.

The ConversationThis article was originally published at The Conversation. Read the original article.


Comments

    I would love to find out more about how to make sure you're getting *enough* iron.

      Are you having cravings for some interior non-gloss paint?

      http://www.nhlbi.nih.gov/health/health-topics/topics/ida/signs.html

      "Signs and symptoms of iron deficiency may include brittle nails, swelling or soreness of the tongue, cracks in the sides of the mouth, an enlarged spleen, and frequent infections.

      People who have iron-deficiency anemia may have an unusual craving for nonfood items, such as ice, dirt, paint, or starch."

      Best way is to get a blood test done. A bit inconvenient, but it's the best way to get a true indicator of what your iron intake is like. While there are general guidelines for men and women, everyone is different and what's "enough iron" for one person might not be enough for someone else. E.g. a pre-menopausal woman that does high-impact exercise (e.g. long-distance running) will generally need more than a pre-menopausal woman that is sedentary.

      Blood tests showed that my iron levels tend to be quite low even though I do get the recommended amount of iron in my diet, so I usually take a good iron supplement for 1 month out of 4.

    Interesting. I'm a gene carrier with slightly elevated levels. Very happy there is some research going on.

    "There is debate among experts over whether everybody should undergo genetic testing for the disorder, even if they don’t display symptoms."
    Yes, it is a tricky one to detect -the iron level slowly increase over years, so you gradually have higher levels of fatigue, you know something is not right, but unless you get a blood test for high levels of ferritin it does not seem to show up until you are fatigued during unusual times (holidays, low stress)
    In my opinion it is really a case of it being better known in the medical General Practitioner level
    In my case I went to three doctors before I found one who could diagnose it
    I was told it is a relatively new on the scene.
    The key to it is that while it is common for females to get blood test looking at iron levels (which indicate the issue i.e. a high Ferritin level), the test does not seem to be considered very often for males(in my experience), so is not detected until "later"

    I do believe this is the condition Dave Hughes (Comedian and all round legend) suffers from - forcing him to donate regularly. Though given how socially aware he is - I'm sure he'd be doing it anyway.

    He is the one that gave me the nudge to start donating regularly and now we have regular blood drives in our office complex.

    Yeah, my Dad suffers from the disease. He has to get treatment for it. My brothers and I are all carriers, but the disease isn't active in us. ...Yet.

    Edit: It's always amusing when you go to research things which are the OPPOSITE of the problem everyone else has. Like trying to gain weight. It really does make things harder. And you get NO sympathy, nevermind the fact that you may be suffering or as uncomfortable as anyone who has the opposite problem.

    Last edited 29/01/14 2:06 pm

    Last time I went to the website for donating blood, there was a restriction for donating if you had high iron levels. You had to have a doctors clearance. Has this changed?

      At the holden foundry in Melbourne they used to love it when they would donate blood because of their high blood iron levels.
      Though for someone with naturally high iron levels it could be due to other possible medical conditions.

      Yes Cups, you do need a clearance -like a specialist ( I know this), or probably a doctors clearance, but YOU CAN get blood taken from the the Red Cross

      From what i can understand, the Australian Red Cross can use some " parts " of your blood, and want to be as close as possible to sure there are not any underlying issues (p.s. they throw away some "parts" of your blood
      Otherwise, you can get a referral to a specialist from your doctor, the specialist will write a request for a hospital (pathology) to take the blood (as a free service). Note this option is harder as you have to book in well ahead (months)

    Hi Cups
    If any of your family have Celiac (gluten intolerance), and you are feeling fatigued (or not),I think it would be worth considering having a blood test looking at the Iron ( Ferritin) levels, which will check for both
    Detail
    --------
    In my case, the thing that prompted me to get an Iron test was that one of my nieces was diagnosed with Celiac (gluten intolerance), so I thought thought it was something to investigate and do a Iron (Ferritin) "blood" test, which showed abnormally high levels of iron, which was eventually diagnosed as Hemochromatosis
    I have since found that out Celiac and Hemochromatosis share the same gene mutation, and some say there is a 50% chance it will be either one or the other (sometimes both), so it can be a good avenue of investigation

Join the discussion!