Iron RDAs - were ALL pre-industrial women anaemic?

Factual Questions
1

A bit of background first…

Some months ago I got pregnant. Among the various tests that the hospital did around that time was a blood test for haemoglobin levels, which came back with the result that I was pretty much skirting the bottom boundaries of “acceptable”

“Eat more iron things” they said. “Here’s a pamphlet. And by the way, pregnant women need more iron than normal”

“Surprise surprise” thinks I (knowing my own history), file the pamphlet with the other half-a-dozen, and embark on my tried-and-tested iron-improvement strategies (bye-bye coffee, hello OJ,red meat,lentils and spinach)

6 months later, I get tested again, and I’ve barely improved at all (gone up by a whopping great 2% - hah!). So this time, they give me another pamphlet, and this one has the actual RDA of iron for a pregnant woman (whereas previously I just got some handwaving about eating “more”)

HOLY FUCK! The number they’ve got here is more than twice as much as normal No wonder I wasn’t reaching my target very fast! I thought I was doing well by upping my intake by 50%!

So I sit down and go over the numbers, and determine that it’s not going to be that difficult for me to get within the “pregnant RDA” from now on. BUT - the only way to do this seems to be to rely heavily on iron-fortified foods and/or pills. Which is fine for me, a twenty-first century Westerner. But neither of these things were available before the beginning of the last century.

So how come every single woman before then didn’t have a case of galloping anemia? Or did they?

These are the numbers I’m looking at here:

Iron RDA for a pregnant woman: 22-36 mg (compared to 12-16 normally).

Without useful things like iron-fortified cereals (up to 10 mg per bowl) or Ovaltine (5mg a cup), this is what you’d need to eat to reach that target:

Red Meat (2.5-4.0mg/100g) - 900g (which is about the total weight of food I’d expect to eat in a day, full stop. In other words, if I ate nothing but meat for the whole nine months, I could just cover my iron requirements. And this is supposed to be the best natural source of iron!)

OR

Lentils (4.5-5mg/cup) - 5 to 7 cups (this is a bit more than what I’d expect to be able to manage if I ate nothing else but lentils all day)

OR

Spinach(4.5mg/cup) - 5 to 8 cups

OR

Cashew nuts(3.1mg/50g) - half a kilo

OR

Dried apricots(5.2mg/cup) - 4 to 7 cups

These were all the most iron-rich foodstuffs in the various different categories - everything else had much less.

So it seems to me that if you restricted yourself only to “natural” non-iron-fortified foods, then it would be flat-out impossible to get up to the RDA of iron for a pregnant woman unless you restricted your diet to only the half-dozen or so most iron-rich foods on the planet. As soon as you start adding anything else like bread or rice or yoghurt, you quickly reach the point where the sheer volume of food you need to eat exceeds the amount that any normal person would consume in a day.

So what gives? How can the “recommended” levels be so difficult to reach without supplements of some sort? How did women ever manage to have half-a dozen kids without all keeling over from anemia Moreover, it must be possible to process iron more efficiently than the average human (because people with haemochromatosis do it), so why don’t we?

2

Chicken livers: 8.5mg/ 3.5oz (~100mg)
Beef liver: 6.8mg/3.5oz
(http://www.health.umd.edu/Library/Handouts/dietapp.html)

Cooking in cast-iron cookware can add up to several mg of iron to the food
(http://www.goaskalice.columbia.edu/2378.html)

3

Pregnant women aren’t allowed to eat more than 50g of liver a week. Too much vitamin A - bad for the kid.

Good thought though. And I like the cite on cast-iron cookware - are non-stick fryingpans the problem? :smiley:

4

Weren’t women smaller then? Height is a linear measurement but volume is a cubic one, so being 6" taller makes a huge difference.

5

I remember something in another thread about some anemic people having an urge to eat clay or dirt.

6

How truly, realworld accurate are government RDA levels anyway? This stuff, like the Food Pyramid and cholesterol recommendations seems to change so often (Margarine’s good! No it’s bad! Eggs are bad! Well maybe not so bad. Take more! Take less! It doesn’t matter!) with every new study, that it almost gives the impression that researchers are almost pulling this stuff out of their ass with respect to what is necessary for humans to do well and prosper.

7

A couple of points:

Back in the good old days when there was hard labor involved in everyone’s daily life, people did eat a greater amount of food than a person of average weight eats now, simply because they required more calories to maintain body weight. This would help in getting the proper amount of essential nutrients.

Cast iron cookware is a Good Thing for the anemic.

Just as people with hemochromatosis retain too much iron, there are probably some people out there who have trouble hanging on to it, and you might be one of them. (Note that hemochromotosis is actually an asset to a woman of childbearing age, particuarly if she’s having kids, which might account for why the trait has been maintained in the population. Women with the gene don’t start suffering ill effects from it until after menopause)

Yes, it probably was pretty common for “pre-industrial”, as you put it, women to be anemic.

8

[small hijack] yeah, I know “pre-industrial” was a pretty inaccurate way of expressing my intended meaning … there doesn’t seem to be any way of saying “people-who-lived-before-the-invention-of-modern-dietary-supplements” snappily enough to fit into a title.
[/hj]

Anyway, back to the topic at hand…

I don’t think it’s just me being a bad iron-fixer … the problem seems to be that I don’t tend to eat iron-fortified foods unless I’m explicitly trying. But that just brings me back to the original question - why is so much fortification needed in the first place?

I guess, on reflection, the thing that surprises me is that it seems to take up so much more of one’s daily diet to get “enough” iron than to get enough of any other vitamins or minerals. For instance, this is what you could eat to get to the “pregnant RDA” of some other useful vitamins and minerals…

Vitamin C: An orange
Calcium: 150g cheese
Vitamin B6: 3 potatoes
Vitamin B12: 100g beef
Vitamin A: A carrot
Folate: 2 cups of spinach and 2 cups of orange juice

Any of these are achievable at one meal (ok, only just achievable in the case of folate), whereas with iron you have to spend all day eating the stuff

this page claims that 30% of the world’s population is iron-deficient. (Probably mostly women.)

I would have thought that the default state for women before the 20th century was probably “pregnant half the time over the age of 20”. So it seems like our bodies ought to be more well-adapted to absorbing iron (compared to blokes, who hardly need any). And now that we tend to spend less of our lives having babies, it should be the case that women’s iron levels would be quite high most of the time - maybe even uncomfortably high - and only dip down during pregnancy. But the situation seems to be more like most women have normal levels most of the time, and then need to make a real effort during pregnancy. As if our bodies weren’t very well adapted to being pregnant. Which seems ridiculous…

9

Aspidistra: Evolutionarily speaking, you only have to live long enough to successfully raise two or three children to reproductive age. After that, you’re beyond the scope of Darwin’s machinations and are, as far as the species is concerned, a null.

Nature’s not much interested in individual worth, is it?

Anyway, `healthy’ is a relative term: Barely scraping by could be sufficient to perpetuate the species, and that’s all a species needs to hang in there.

10

And of course, not so very long ago a lot of women died in childbirth. Many babies and young children died, too. Or were sickly. One reason people a hundred or two years ago were smaller was that they were not as well-nourished. So you’re probably right that a lot of people (not just women) in prior centuries were not operating at their full potential, suffering from anaemia and other deficiencies, especially the poorer ones. But as Derleth said, all that’s needed for the species to survive is that on average 2 or more children of each woman live to puberty. Obviously some hardy and lucky ladies had many more than that; it’s not uncommon to read of women who conceived a dozen or more babies, of which many died young.

11

Women’s periods tend to keep their iron-level down. I remember seeing a nice chart showing average iron levels of male and female: equal until adolescence whereupon the females promptly averaged marginal, ie the average level for women was right at the borderline for males where they would be considered below recommended levels. Then at menopause, women’s average levels went back up to men’s average levels.

Being on the Pill reduces the loss, and made the women’s levels match the men’s.

I believe the word for “anemic” was “greensick” in the Middle Ages, and referred to female anemia.

Then this woman on the borderline gets preg’, and need to build up the baby. You have a good question. Maybe it takes less iron to build one baby than have 9 periods?? How much iron does it take when nursing? Here’s hoping modern science is exaggerating somewhat the need for iron during pregnancy. Or the points prior posters made count enough to make the difference.

Then it used to be said that mothers would have cavities during pregnancies, because babies used up a lot of the mother’s calcium. Does anyone know if there’s anything to that?

12

Many of those RDA’s are simply the minimum recommended to avoid getting some disease like scurvey or ricketts, not neccesarily to maintain good health. There are many books and sites that give more detailed looks into who should get how much of each vitamin.

Most men probably have too much iron in their diets, it is a potent oxidizing agent. Western women probably receive all they need from their diets, unless they are vegetarian.

13

I doubt it, since IIRC, your teeth aren’t taking anything from your blood once they’ve formed and erupted through the gums. After that, they can be remineralized with special mineral-containing mouthwashes, but I doubt that low blood levels of calcium would affect much. Maybe pregnancy changes something else in womens’ systems that predisposes them to cavities, like salivary pH or something.