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Iron Deficiency and Fatigue

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Many patients with fatigue as a main complaint are eventually diagnosed as having an endocrine problem. However, an often overlooked reason for fatigue in women who are menstruating is iron deficiency. Iron is needed for thyroid hormone biosynthesis, including the conversion from the inactive thyroid hormone, T4, to the active hormone, T3. Women taking thyroid hormone are especially likely to benefit from treating iron deficiency. Men are unlikely to be iron deficient, as the
main reason for low iron in younger patients is loss through menses.

That severe iron deficiency leads to anemia, as manifested by low hemoglobin and hematocrit on a CBC blood test is well-known. However, mild iron-deficiency leads to low ferritin in blood tests BEFORE a drop in hemoglobin and hematocrit occurs. An article published in the May 2003 British Medical Journal showed that patients with low ferritin, but normal hemoglobin and hematocrit, have fatigue that is reversed by iron treatment. Since Dr. Friedman’s goal is early diagnosis of treatable diseases, he recommends measuring a ferritin level in all women who have fatigue. Performing a CBC is not needed.

Colon cancer can also give a low ferritin level, but it is unlikely in younger females whose main complaint is fatigue and who do not have weight loss. In men or older women, a low ferritin may warrant a colon cancer work-up, depending on evaluation by the patient’s primary doctor.

The normal range for ferritin is usually between 30 and 300 mg/dL, but Dr. Friedman recommends iron treatment for everyone with a ferritin less than 60 mg/dL. The goal of treatment is to raise ferritin levels to a value between 70 and 90 mg/dL and is usually achieved with oral iron treatment. Raising ferritin levels to this range may be needed for patients with hypothyroidism to have an optimal response to thyroid hormone treatment. Dr. Friedman’s philosophy is proper ferritin levels are crucial for good hormone health, and he advocates attempting to raise them fairly rapidly.

Ferrous sulfate (325 mg orally, available over the counter) has usually been the recommended treatment; however, this preparation is often poorly tolerated.

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EmpowHER Guest

Excellent iron supplements that I have taken are Floradix iron plus herbs and Enzymatic Therapy's Ultimate Iron. Both use very gentle, absorb able iron, ferrous gluconate, and ferrous succinate. They do not constipate or cause any digestive issues at all. You can read many glowing reviews of Ultimate Iron at vitacost, and also many for Floradix at amazon.com. If you get a gentle easy to digest iron, it actually helps constipation. One of the symptoms that I have found listed for iron deficiency is constipation. I have struggled with it just about my whole life, but I have been amazed at how this has disappeared since getting my iron level up. I have also been eating a lot of probiotic foods for some time now, such as kombucha, kefir and homemade sauerkraut. That helped, but I have seen even greater improvements since dealing with the iron deficiency. Ultimate Iron works just as well as Floradix and is way cheaper. You can get it at swansonvitamins.com or vitacost.com for about 12 dollars for a bottle of ninety softgels, which lasts a month and a half if you take it at the dosage of two gels a day recommended one the bottle. You absorb about 16 mg of iron from 2 softgels which are about 50 mg. of ferrous succinate. The absorption rate of ferrous succinate is about 32 percent. I take three softgels a day, as less than this doesn't improve my symtoms as well as three. I have been taking for about a month and a half and will retest my iron level at about three months.

November 9, 2010 - 10:18pm
EmpowHER Guest

I had moderate fatigue and hair loss and ferritin level below 20. (To me, the fatigue was debilitating, but technically not "severe" as I was still able to physically get out of bed and drag myself to work at a desk job.) With ferritin levels below 20, I used IronSorb for about a year with no improvement. I was switched to ferrous sulfate (standard cheap drugstore tablets) and my levels finally began to rise. However, a year and half after using ferrous sulfate at 3-4 tablets (65mg each) a day (sometimes I can't tolerate 4 tabs due to headache), my ferritin is still only 40.

The fatigue improved by half within several weeks after starting ferrous sulfate and the hair shedding is somewhat improved, though it is still higher than normal.

I wish I knew what I could do to increase my ferritin to the recommended levels of 70+ to stop the hair shedding, but I am already taking the maximum amount of iron I can tolerate without headaches.

June 22, 2010 - 4:57pm
EmpowHER Guest
Anonymous (reply to Anonymous)

Does anyone have a solution for her? Except intravenous iron. I think I have to try that unless I find something else, although I am a healthy male. Just low ferritin.

June 11, 2016 - 6:31am
EmpowHER Guest

You can read more about iron deficiency anemia here:

June 21, 2009 - 1:27am

I was anemic as a child, and also had to take iron supplements during my pregnancies. Unfortunately, iron supplements and I don't get along very well.

So, I developed a ritual of having liver and onions at least once a month. I happen to like liver and onions, so that's a good thing. My doctors have long advised me to have a little red meat, but I can't digest that very well. Funny how liver doesn't affect me the same way. I love spinach, mollusks, lentils and other iron-rich foods.

While I'm at it, here are the Top 10 Iron-Rich Foods.

June 17, 2009 - 4:31pm

I'm currently anemic, and was told it most likely was because of my long distance running. I'm taking Slow Fe, a slow-release iron pill, and I'm wondering how it measures up to Dr. Friedman's recommended supplements.

June 17, 2009 - 4:18pm
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We value and respect our HERWriters' experiences, but everyone is different. Many of our writers are speaking from personal experience, and what's worked for them may not work for you. Their articles are not a substitute for medical advice, although we hope you can gain knowledge from their insight.


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