A Discussion on Iron and Health with Leo Zacharski, M.D.

Iron fortified anvil

Leo Zacharski, M.D., is a hematologist, oncologist, and professor at the Geisel School of Medicine at Dartmouth, and is arguably the world’s leading expert on the relation between iron and disease. He’s done pathbreaking studies, including clinical trials, on the effects of iron in cancer, cardiovascular disease, and diabetes. Not least among his accomplishments, he wrote the preface to my book, Dumping Iron. Dr Zacharski sat down with me to discuss both the basics on iron and health and the most recent developments, many of which he has a hand in discovering.



Admittedly, this video ran into overtime. So, in case you want some highlights, here are a few:

Beginning: I ask Dr. Zacharski about recent developments in iron, and he gives an excellent summary of the evidence for iron in cardiovascular disease, cancer, and diabetes.

10:30 – I ask what are the most important determinants of excess ferritin, whether metabolic dysregulation, alcohol, iron fortification, etc. Dr. Zacharski mentions that Quebec Metal Powders, now known as Rio Tinto Metal Powders, is the major source of food iron fortification in the U.S.

30:00 How much of the worse health from excess iron is driven by very high ferritin levels, e.g. over 600.

36:30 I interrupt to give my little spiel on the relation of evolution to iron to aging.

43:00 How Dr. Zacharski and colleagues figured out the true normal range of ferritin. (Discussed also in this article.)

Some of Dr. Zacharski’s publications that we discussed in this video:

Association of age, sex, and race with body iron stores in adults: Analysis of NHANES III data

Decreased Cancer Risk After Iron Reduction in Patients With Peripheral Arterial Disease: Results From a Randomized Trial

Effect of controlled reduction of body iron stores on clinical outcomes in peripheral arterial disease

Potential Role of Iron in a Mediterranean-style Diet

Ferrotoxic Disease: The Next Great Public Health Challenge

Ferritin and Percent Transferrin Saturation Levels Predict Type 2 Diabetes Risk and Cardiovascular Disease Outcomes

We didn’t get a chance to discuss this one, but this is a great paper by Dr. Zacharski on iron, hypercoagulation, and cancer:

Hypercoagulability preceding cancer


A big thanks to Dr. Zacharski for taking the time to talk with me.

PS: You can read more on this topic in my book, Dumping Iron.

PPS: Check out my Supplements Buying Guide for Men.

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  1. S.L. says:

    Hello Dr. Zacharski,

    Would you be so kind as to take a few minutes to read this article? https://roguehealthandfitness.com/dangers-of-liposuction/. Thousands of people are losing their health, well being, and their lives due to adipose removal procedures. This harm can be prevented.

    Thank you.

  2. Mellie Walks says:

    Wow! Really fascinating! Great interview.

  3. Bill says:

    Well PD, I did watch all of this video. It took a couple of attempts but I did get to the end. It was interesting and worth the effort. But as in university lectures 5 decades ago, I found my attention waning after about 20 minutes. each time :- (

    What to say ? The discussion about diabetes and iron levels in the blood is important and diabetics should High iron damages the beta cells in the pancreas, This reduces the capacity of the pancreas to produce insulin. And thus the cells of the body do not absorb glucose/sugar in the blood. And high sugar in the blood is damaging to many other body organs and the arteries, leading on to CVD.

    I think that diabetics need to take this on board. And it seems that donating blood is a good way of alleviating this situation.

    Finally I wonder if it possible to run a speech to text program over this blog ? My younger brother ( who is a diabetic ) was talking about this process the other day and said it was pretty simple. But I have no idea how to do it. .. :- (

    • P. D. Mangan says:

      Hi Bill, if you mean a transcript of the video, there is a way to do that, not that I know what it is. Something I could work on getting though.

      • Bill says:

        Yes, a transcript of the video. It would take days of effort to do it by hand ( I know because back in the early 1990’s I did this for a while. But if there is a software program which can do it, it would be far easier. And as my brother says, there are such software programs.

      • Nick says:

        Having just casually googled “digital transcription”, it seems to me there are software packages that might do it, but they ain’t free. And there may be open-source development projects for it which would be free, but you’d need to be a programmer or something.

        I just figured there must be freeware programs out there that you could run an audio file through and get a nice text file out of it. Maybe not. If anyone knows of one, I would certainly be willing to do some leg-work in testing it out.

        Thanks for summarizing this interview, and for linking to his publications. I’ve not yet got around to listening yet, but will.

  4. Kevin McHale says:

    I enjoyed the video interview – thanks. As an aside, to bring together the themes of iron overload and intermittent fasting, this study https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4143608/ found that fasting can reduce ferritin levels. Two days of fasting in every 8 days, over a 48 day period, led to a average 28% drop in serum ferritin in the subjects (women aged between 20 and 30). The were allowed an intake of no more than 200 kcal per fasting day. This kind of fasting patten would essentially be the 5: 2 regime as popularised by Dr Michael Mosley in the UK. So, perhaps this fasting patten offers another useful method of iron reduction (in addition to blood donation, chelation etc) ?

    • P. D. Mangan says:

      Thanks, Kevin. I hadn’t seen that particular article, but another which I included in my book showed that fasting increased the iron-regulatory hormone hepcidin, while exogenous growth hormone decreased it, leading to lower and higher iron absorption respectively. Fasting could be a good way of decreasing ferritin, although whether iron absorption increases when feeding is resumed is another question.

      • Kevin McHale says:

        This study struck a chord with me I spent about 2 and a half years doing the 5: 2 before reading Dumping Iron last year. I’m not vegetarian and have always eaten plenty of meat. After reading your book I had my ferritin checked and it was 95 – not too much over the 80 threshold which is recommended. As a 52 yr old man, I was expecting my ferritin to be higher and was surprised it wasn’t too bad. I wondered if all the 5:2 fasting that I did got it down before I did the ferritin test (but of course now i will never know!) I take your point that maybe after a period of fasting, the body could absorb iron at a higher rate than before to try to catch up. Maybe the science will tell us this one day. But I suppose the same could be true after blood donation – when iron is also lost?

        • P. D. Mangan says:

          Yes, you would absorb iron faster after a blood donation, although that would depend on the initial ferritin level. Also, if someone has a lot of ferritin on board, they can make red blood cells very quickly, as much as ten times the normal rate, as I discussed in this article.

          But if a person has a high ferritin and donates blood, they probably absorb iron no faster than before. It’s only low ferritin levels that increase iron absorption.

  5. Demian says:

    P.D., love your site. Just discovered it. I clicked on your link to one of Zacharski’s 2007 studies. The iron-atherosclerosis link seems inconclusive, at least in this study:

    “Conclusion: Reduction of body iron stores in patients with symptomatic PAD (peripheral artery disease) did not significantly decrease all-cause mortality or death plus nonfatal myocardial infarction and stroke.”

    I haven’t listened to your full interview with the doctor.

    • P. D. Mangan says:

      Hi Demian – Dr. Zacharski and colleagues have done a lot of follow-up to that study. For example, they found a much lower rate of cancer in iron reduction. The problem with studying iron reduction is similar to that with studying nutritional factors. In a drug trial, only one group gets a drug, the other getting placebo, so the difference between groups is clear. In iron reduction or nutritional studies, both groups have some level of the nutrient of interest. Everyone has varying levels of iron, so the ultimate levels does not depend solely on phlebotomy, but also on initial levels. In the paper I linked, they found that iron levels were similar in both phlebotomy and non-phlebotomy groups who didn’t get cancer, as well as those who did.

      I discussed the idea that both groups in a trial may have similar levels of a nutrient in an article concerning omega-3 fatty acids. In many trials, the blood levels of omega-3 in both groups overlapped, since lots of people eat fish, and after the year 2000, many people had heard of the benefits of fish oil and were taking it. Overlapping and/or similar levels of omega-3 in both arms of a trial accounts for the failure of some trials to show benefit of omega-3 supplementation.

  6. salem F says:

    My hemoglobin is 167, and my serum iron is 28 , but my ferritin is 54,

    how i can increase my ferritin level up to 80-100, without increasing my serum iron which is now at the top of the normal range ?

    thanks and God bless you

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