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.
Iron supplementation and TSH levels
connection between iron metabolism and hypothiroidsim
Perpetuating The Myth ! (Programme On Radio 4)
Study: "Thiamine and Hashimoto's Thyroiditis: A Report of Three Cases."
How to supplement properly? 
