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Radio 4 Inside Science - about iron supplementation

Just heard inside science talking about iron supplementation which was very interesting. Thought I would post the transcript as so many of us Hypo people also have iron problems. It seems that lower doses on alternate days may actually cause the body to absorb iron better due to evolutionary reasons (our body is designed to continually adapt iron absorption to avoid too much building up, because we not usually have ingested large amounts regularly).

I for one am going to try following this advice. You can listen to the programme on iplayer - bbc.co.uk/programmes/b09ply54 - but here's the transcript if you can't listen:

Zimmerman

That’s right. It is counterintuitive but we found that actually giving a lower dose of iron every other day in a single dose is more effective than giving daily iron doses that are high and split throughout the day. It’s a simpler regimen and it results in about 30-40% higher iron absorption from the supplements.

Porter

Because iron’s quite hard to absorb in this form isn’t it?

Zimmerman

That’s right, the body can’t excrete iron, so it regulates its body iron stores by very carefully regulating iron absorption. We need iron, of course, to produce new red blood cells and iron is essential for life but at the same time too much iron can be toxic actually to the body because iron causes oxidation reactions in the body and can damage cells and damage tissues. So, we very carefully regulate the amount of iron that comes into the body.

Porter

And in terms of the individual dose of those supplements that you’re giving every other day how do they compare to the ones that, for instance, we give three times a day at the moment?

Zimmerman

Yeah well, we give 60 milligrams, 60 milligrams of iron is a high dose but it’s not as high as what’s currently recommended. Usual recommendations for iron supplements are for 60 milligram dose three times a day, so a total of maybe 120-180 milligrams per day. So, we gave about one-third of the usual recommended dose. And what we’re realising is that the body very carefully regulates absorption and it doesn’t like to see high doses every day, it likes to see doses given at smaller levels and given every other day. And basically, I think that our research will lead to a shift away from larger doses to more moderate doses and dosing regimens that aren’t daily or split during the day but rather a new regimen for iron supplementation might be three doses a week, maybe given on Monday, Wednesday and Friday, first thing in the morning before breakfast. So real simple.

Porter

Is this response explicable in evolutionary terms? I’m imagining that historically, many thousands of years ago, we wouldn’t have come across many natural sources of iron and maybe it might have once every three or four days and you had to make the most of it there and then.

Zimmerman

Very true, it could be because in the old days we’re not used to seeing in our diets the large doses of iron that are provided in oral iron supplements. For example, we’d have a meat meal, maybe every few days, which would provide a large dose of iron and, yeah, the body adapted to this idea that you might occasionally have large doses of iron but you had to be careful not to have too many large doses of iron too often because that would lead to too much iron in the body.

Porter

So, if you have a lot of iron in your bowel, paradoxically that’s actually shutting the door to absorption, so you absorb less, is that what you’re saying?

Zimmerman

Yeah, that’s what happens is as you take an iron supplement and iron is absorbed into your bloodstream it stimulates the production from the liver of a small peptide, a small protein, called hepcidin and hepcidin essentially closes the door to further iron absorption from the gut into the bloodstream.

Porter

So, the more often you have iron in the bowel the more often you have hepcidin floating around your system and closing that door?

Zimmerman

Right. So, we think that in the long term if a woman was to take supplements every other day this increase in absorption would lead to quicker recovery from anaemia.

Porter

One of the other problems with iron therapy of course is not just the response of the blood but side effects and that’s often attributed to unabsorbed iron. On your regime are women likely to have fewer side effects from the iron?

Zimmerman

Yeah, well I think besides the advantage of better absorption the every other day regimen may lead to less gastrointestinal side effects. We found in our study that there were 33% less gastrointestinal side effects in the women who took the supplements every other day versus every day.

Porter

Michael Zimmerman talking to me from Zurich. And listening to that in our Glasgow studio is Dr Margaret McCartney. Margaret, people may be surprised that existing iron courses aren’t based on evidence.

McCartney

Well I was surprised as well Mark and I have to say I feel a bit ashamed as well, looking at the lack of evidence for how often we should give iron, it’s quite clear that there have been uncertainties about this for decades and yet the amount of trials on how to deal with this super big problem, it’s such a common thing, I’m sure most doctors are prescribing iron most days in general practice, the lack of trials about this really is astonishing.

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Thanks for posting this Raucous, very interesting.

Did they say what particular form of iron supplementation they're referring to? I can't see that mentioned in the transcript.

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No I don't think they did, it's quite a shirt programme & they cover about 3 different topics so prob not time for that much detail. My guess would be they will be talking about the type that is most often prescribed by the NHS but maybe we can find the research referred to online somewhere....

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Really interesting, thanks! I think I’ll actually try that and see the effect. I’m just looking to improve levels.

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Thank you from me too.

The one worry I have about the discussion was that they rather equated ferrous fumarate (or whichever other supplement) with consuming meat. Yes, both contain iron. But iron in the form of haem or ferritin - which is what you get in meat - is absorbed by different pathways to ferrous fumarate. (I don't know if hepcidin affects haem and ferritin absorption.)

If I were iron deficient, and I have no reason to believe I am, I think I might choose an even lower dose of ferrous fumarate but also add a low dose of haem and/or ferritin as well. No argument with alternate days - it does give the gut a chance to recover between doses. I wonder if that combination would be effective?

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I'm vegetarian, aside from NDT, so choose to take two forms on non-haem iron as my ferritin's a bit low, & ferritin supplements are animal based. I stopped taking ferrous fumarate as it caused digestive issues, then later read it's not a natural food/mineral form, but an industrial by product. I'm wondering if that affects hepcidin production?

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Yes it would be good to know a bit more in depth....

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Of course you do have to watch out if you are one of the population who can't produce hepcidin, which I think is the people with haemochromatosis. I have one gene for this, but due to still having periods I'm low on iron. However as soon as my periods stop, I'm going to strictly avoid all iron supplements. I do think it's bad that so many multis contain iron. As with so many things, we need to be Goldilocks!

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Thanks, that is very interesting. Might try spacing my doses, am very aware of not taking too much.

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My GP advised me to cut back to every other day a few months ago, after the surgery had had a talk from a consultant haematologist.

I no longer feel nauseous after taking it...It is a bit more difficult to remember if you are not taking every day, but I am now doing so regularly.

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Thank you so much for this. Im new (just knowing my blood count is low with ferritin level not optimal for hypothyroid and also new to this forum) so my supplement consumation is still pretty much all over the place 😅

Im taking salus non heme liquid iron 40ml (divided 20ml day & night dosage) for 4 days now and since day 1, i have black stool - which might be caused from unabsorbed iron (correct me if im wrong) its an expensive liquid iron and im pretty baffled why but continue on with the dosage (with still same effect but no tummy discomfort or nausea whatsoever - i feel slightly energized)

It has vit C (100mg) included for better absorption and i also take extra 1000mg (free acid form) vit c but still having black stool. Is it normal? Do my body even absorb the iron at all? :(

Today morning i stopped taking it upon waking up - to follow above’s suggestion. ill alternate days. I take my prebiotics instead on empty stomach. Is 10billion cfu enough or i need more? Thanks in advance

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