Earlier this year I came across P.D. Mangan’s research on iron, and how having excess can negatively affect health.
If you’re not already familiar with that, he has a great book called Dumping Iron, which I’ve reviewed and summarized here.

He specifically singled out the ferritin protein as our bodies’ store of excess iron. Thus making it a useful biomarker to track.
Armed with this knowledge, I went back over previous blood tests I had done to see what my ferritin results were like. This is what I found:
Date | Result | Blood Test Type |
August 2018 | 161ng/ml | Venous blood draw |
June 2019 | 232ng/ml | Venous blood draw |
Feb 2020 | 132ng/mL | Venous blood draw |
May 2021 | 244 ng/ml | Venous blood draw |
None of these results had been flagged up as an issue on my blood tests, as they had all been “within the reference range”.
Unfortunately, what I hadn’t known at the time of getting the blood test results:
- The reference range for most, if not all the biomarkers, bares little relationship to what’s healthy and optimal. Instead it’s simply the range that the central 95% of a test population are within.
- Research that P.D references suggests that optimal is somewhere under 100 ng/ml – and thus all my results were non-optimal. Jump to this section of my other post for more details on the optimal range.
What does this mean?

The upshot of having had elevated ferritin over the years, in line with the hypothesis presented in P.D. Mangan’s book, is that I’ve been inadvertently been doing extra damage to my body without realizing it. The damage will primarily come in the form of free radical damage, which is something you wouldn’t notice or experience on a day to day basis.
It’s something that accumulates slowly over time.
There doesn’t appear to be anything you can do about it in retrospect. All you can do is reduce the potential for damage going forward. Actually, that’s like many things in life!
The Current Solution?
There are 3 potential ways to reduce ferritin levels, ordered from fastest to slowest:
- Donate blood
- Use iron chelating supplements such as curcumin or IP6
- Cut down iron sources from the diet, and be patient as the iron gradually lowers
Given that I’m not particularly patient, I went for option #1.
I’d never donated blood before, as I have some “issues” around blood – in that it makes me go a bit queezy and weak. In the past I have had to be careful about not passing out after blood tests.
However, in this instance I was determined to get this potential issue sorted.

How do blood donations lower iron?!
Approximately 60-70% of our iron stores1The roles of iron in health and disease – Yang et al. (2001) – see paper intro section are found in hemoglobin in our blood. Therefore, by taking out ~450ml of iron rich blood, we force our body to have to replenish it. When it makes new blood, it draws on its iron stores, as well as the iron in the diet. This therefore reliably reduces our ferritin level. As ferritin is where our body primarily stores excess iron, this then reduces the systemic level of iron in our bodies.
Blood Donations for Lowering Iron
Here are a few things I learnt about blood donations in this context:
- Lots of Exclusions – There are a lot of potential reasons why people aren’t eligible to donate blood. Some of them make a lot of sense, whereas others seem overly cautious. The donor center will run through a number of questions each time you visit, and certain answers will disqualify you.
- Hemoglobin Testing – One thing they do prior to you donating blood is testing your hemoglobin level. Hemoglobin is an iron rich protein found in your red blood cells that gives them their color. They test your levels to make sure you’re not already iron deficient… because if you were… depleting it further via blood donation would not be good! However, there’s a nuance. They have to pick a minimal threshold and stick to it. However, in practice, some people are naturally below that level, even though they’re 100% healthy and not anemic. For those unfortunate people, they won’t let you donate.
- Cost = Free – In most countries, blood donation is free, and relatively easy. You simply find your national blood donation organization(s), and sign up for a day when they’re accepting donations.
- Hydrate Prior – On the day, you want to make sure you’re well hydrated before you give blood. I think this is from a health perspective primarily, but it may also speed up the amount of time it takes to give the donation (not sure). They also encourage you to have eaten before donation. Personally I donated without eating once, and was fine after. Perhaps part of it depends on how comfortable your body is with fasting.
- Prepare for 24h of weakness – Everyone reacts differently after blood donations. Some people can continue normally, whereas others need to “take it easy” for 24 hours to let their body recover. Personally I’m in the latter group, and typically found I need 2 sleeps after blood donation before I’m back to 100%. Mainly in the context of high output exercise.

^ I generally agree with all these tips. However, I personally never upped my salt intake and it was all fine
What if you can’t donate?
If you can’t donate blood for some reason, but still want to go the route of phlebotomy (the fancy word for extracting blood via your veins), then you’ll need to work privately with a phlebotomist. Every country will have a certain number of mobile phlebotomists, or perhaps phlebotomists who work in private clinics. It will simply be a case of reaching out to them about what you’re looking to do (give blood), and seeing who is happy to charge you for the privilege!
Of course, one key difference is that the blood would then get “dumped” rather than going to a donee. However, there isn’t much you can do about that!

^ Example of someone getting phlebotomy in the comfort of their home
So did it work?
Yes! It worked.
My last blood test showed a level of 244 ng/ml of ferritin. Therefore, based on frequently cited estimates2The Risk of Too Much Iron: Normal Serum Ferritin Levels May Represent Significant Health Issues – William R. Ware (2013) that 1 donation lowers ferritin by ~30 ng/ml, I decided to start with 3 blood donations before re-testing ferritin, which would have taken me closer to 144 ng/ml.
To my surprise, upon retest, my ferritin result was 46ng/ml – much lower than any other test I’d had in the last 3 years – and under the ~100 target I was aiming for.
Then as a follow-up 6 weeks later I did a second finger prick test to check my ferritin. I had been eating lots of red meat, and was curious how quickly the ferritin level might have shot up.
Well, the result came in at 42 ng/ml, so effectively the same again, which was interesting. It hadn’t gone up quickly like I feared. So that was my target achieved.
Important caveat: Whilst the above worked for me, I am not a doctor, and this is not a suggestion or recommendation that you do the same. Please work with your doctor to find what’s best for your personal health needs.
Next steps?
Longer term, I plan to maintain a lower ferritin level by doing 1 to 2x blood donations each year.
In my Dumping Iron book review, I linked to research (below) showing that 2 donations per year makes a significant difference to ferritin range3The Risk of Too Much Iron: Normal Serum Ferritin Levels May Represent Significant Health Issues – William Ware (2013), but more than that had diminishing returns.

^ Image from this paper, which utilizes data from this Danish study
Roundup
So there you go, for me personally, 3 blood donations of ~450ml each were enough to take me from ~245 to ~45 ng/ml of ferritin.
From there, I’m working on a cadence of 1 blood donation every 6-12 months.
Everyone will be different, but hopefully this is a useful data point if you’re looking to do similar.
References
- 1The roles of iron in health and disease – Yang et al. (2001) – see paper intro section
- 2The Risk of Too Much Iron: Normal Serum Ferritin Levels May Represent Significant Health Issues – William R. Ware (2013)
- 3
Awesome post!
Should we consider serum iron levels at all? If so, what is an optimal range?
Thanks in advance.
Hi Sam.
It’s a good question. It appears that serum iron is an unreliable biomarker of iron excess, and instead serum ferritin (and also transferrin saturation) are used.
This paper looks at screening methods for diagnosing extreme iron overload (hemochromatosis), and says, quote:
If I were to speculate on the rationale, it may be because the body regulates serum iron by moving the excess from the blood into ferritin, and also into soft tissues. Therefore, serum iron value may stay stable, whilst iron accumulates in excess elsewhere.
The reason that it’s possible to fixate on ferritin, and to some extent ignore transferrin saturation, is that as you decrease ferritin, you will reliably decrease transferrin saturation.
Personally, when my ferritin 244 ng/ml, my serum iron was 112 mcg/dL / 20 umol/L
Then after 3 blood donations, my ferritin was 42 ng/ml and my serum iron was 90 mcg/dL / 16.2 umol/L
So the serum iron did drop, but not at the same ratio to ferritin.
Thanks a lot John! Really good work you’re doing on this website. Can’t thank you enough.
Thanks Sam! This subject really interested me, so I went deep. Not sure why it’s not talked about more in the mainstream. Perhaps a combination of lack of awareness, mixed with a lack of financial incentive.
Just discovered your page and I’m so glad for it. It is of so much significance to my life.
Incredible post too!
Hi Mario! Thanks for the comment, and glad to hear the content is of use!