[senior citizen]

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[blueash]

simplist (oversimplification) is that Iron exists in two forms:
Ferrous iron is Fe+3 (trivalent)such as ferrous sulfate (FS) and Ferric iron is Fe+2 or bivalent.

From Ferrous versus Ferric Oral Iron Formulations for the Treatment of Iron Deficiency: A Clinical Overview

"bioavailability of iron ferric preparations is 3 to 4 times less than that of conventional FS [20]. This is due to the extremely poor solubility of ferric iron in alkaline media and the fact that ferric iron needs to be transformed into ferrous iron before being absorbed"

What that means is that ferric iron does not get into the blood stream because it does not dissolve well in the intestine. The human intestine does a far better job maintaining iron balance when you eat ferrous iron. And ferrous iron is animal iron (hemoglobin, thus heme iron) or more commonly in iron supplements. Ferric iron is plant iron. Now this is not a complete explanation of heme vs non-heme nor the relative merits of different iron sources but the take home message is that animal sourced iron is better absorbed and it the preferred source especially for those at risk of iron deficiency anemia. Interestingly as a side note, spinach which has a lot of non-heme iron also contains a lot of oxalate which is a compound which actually seems to inhibit the absorbtion of iron. So you can't just look at 1 mg of iron as 1 mg of heme iron is 3 to 4 times more bioavailable than 1 mg of non-heme.
Sorry long post

[graciegirl]

Originally Posted by blueash

simplist (oversimplification) is that Iron exists in two forms:
Ferrous iron is Fe+3 (trivalent)such as ferrous sulfate (FS) and Ferric iron is Fe+2 or bivalent.

From Ferrous versus Ferric Oral Iron Formulations for the Treatment of Iron Deficiency: A Clinical Overview

"bioavailability of iron ferric preparations is 3 to 4 times less than that of conventional FS [20]. This is due to the extremely poor solubility of ferric iron in alkaline media and the fact that ferric iron needs to be transformed into ferrous iron before being absorbed"

What that means is that ferric iron does not get into the blood stream because it does not dissolve well in the intestine. The human intestine does a far better job maintaining iron balance when you eat ferrous iron. And ferrous iron is animal iron (hemoglobin, thus heme iron) or more commonly in iron supplements. Ferric iron is plant iron. Now this is not a complete explanation of heme vs non-heme nor the relative merits of different iron sources but the take home message is that animal sourced iron is better absorbed and it the preferred source especially for those at risk of iron deficiency anemia. Interestingly as a side note, spinach which has a lot of non-heme iron also contains a lot of oxalate which is a compound which actually seems to inhibit the absorbtion of iron. So you can't just look at 1 mg of iron as 1 mg of heme iron is 3 to 4 times more bioavailable than 1 mg of non-heme.
Sorry long post

Blueash is an excellent source of information on this subject. And on many other scientific subjects.

[senior citizen]

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[Indydealmaker]

If anyone is interested, I can ship iron sulfate to you in 45,000 pound truckloads. Just let me know when you want it dumped in your driveway!

[Villages PL]

Originally Posted by senior citizen

So, even though we've all been told to avoid too much red meat, it seems necessary for iron. Ditto for turkey which does have heme iron.

Most of the iron we have in our body gets recycled. We lose iron when we lose blood or skin cells etc. But I would assume that most of us are not losing any significant amount of blood (unless you are one of those who likes to donate blood).

At any rate, before somone starts eating red meat just because of the iron it contains, they should at least know if they have iron deficiency. Hopefully, your doctor would have told you if you have a deficiency. We only need very small amounts of iron and too much iron can, potentially, be damaging to the body. It can damage your liver and other organs.

I've been a vegan since 2006 and my yearly blood work has never indicated iron deficiency.