cast iron 2A large body of thyroid patients, men and women, have been surprised to discover that being hypothyroid also results in having too low levels of iron. And iron is a very important mineral in many ways! Check out this information to help you in working with your doctor. 


How do I prepare for iron labs?  Although the vast majority of doctors, medical websites and even lab facilities will state to be off iron for a good 12-24 hours before testing, the American Hematochromatosis Society says to, “Refrain from iron pills for a week prior to the tests.”  i.e. you want to see what your body is hanging onto and treat that. Five days is probably enough, but you decide.

Which iron labs do I need? 

Patients have found these to be very important:

  • FERRITIN (storage iron)
  • SERUM IRON (the circulating iron)
  • TIBC (Total Iron Binding Capacity, aka carrying protein. It should go higher when iron is low)
  • % SATURATION (also called % transferrin saturation)  (ratio of serum iron and TIBC)

This page gives you a general idea of what you are looking for in all these labs.  Lab results have nothing to do with just “being in range”, patients have noticed in each other’s labwork.

Can I ONLY measure ferritin and treat my iron based on it alone? Big mistake, say patients! You can have so-called “normal” or even optimal serum iron and saturation levels, and even normal hemoglobin and hematocrit, yet a low Ferritin. And some patients report continued problems raising desiccated thyroid even with just low ferritin while the other labs look good. See the heading below titled QUESTIONS PERTAINING TO IRON RESULTS.


Why do we, as thyroid patients, often have low iron levels? Because being hypothyroid can result in a lowered production of stomach acid which in turn leads to the malabsorption of iron. Additionally, being hypo can result in heavier periods for women, which causes more iron loss.

Why is having low iron levels a problem for hypothyroid patients and what are symptoms? First, though the slide into low iron can be symptomless, patients notice it eventually becomes the precursor to being anemic, revealed by the other iron labs–saturation and serum iron. And once the latter occurs, patients then have symptoms which mimic hypothyroid–depression, achiness, easy fatigue, weakness, faster heartrate, palpitations, loss of sex drive, hair loss and/or foggy thinking, etc, causing a patient to think they are not on enough desiccated thyroid, or that desiccated thyroid is not working. Excessively low Ferritin as well as low iron can also make it difficult to continue raising your desiccated thyroid, patients have reported, resulting in hyper symptoms when raising desiccated thyroid.

In turn, having low iron levels decreases deiodinase activity, i.e. it may be slowing down the conversion of T4 to T3.  Biologically, insufficient iron levels may be affecting the first two of three steps of thyroid hormone synthesis by reducing the activity of the enzyme “thyroid peroxidase”, which is dependent on iron. Thyroid peroxidase brings about the chemical reactions of adding iodine to tyrosine (amino acid), which then produces T4 and T3. Insufficient iron levels alter and reduces the conversion of T4 to T3, besides binding T3. Additionally, low iron levels can increase circulating concentrations of TSH (thyroid stimulating hormone).

Even worse, good iron levels are needed in the production of cortisol via the adrenal cortex. This study reveals that an iron-containing protein is present in high amounts in the adrenal cortex and is involved in the synthesis of corticosterone.  So by having low iron, you can potentially lower your cortisol levels.

Iron, in addition to iodine, selenium and zinc, are essential for normal thyroid hormone metabolism.

Does inflammation lower my iron levels?  With inflammation, ferritin (storage iron) goes up, up and iron goes down, down. Gluten can cause inflammation for those with Hashi’s. Even without Hashi’s, thyroid patients can have chronic inflammation in their joints. An allergy to what you eat can cause inflammation, as happened to thyroid patient Deb who discovered she was allergic to eggs. Once she removed eggs, her iron went up! To see if you have inflammation, go here.


(As reported by patients; not in any particular order; you may have some, not others)

Heart palpitations
Light-headed, sometimes like head is going to pop
Easily short of breath
Burning in legs (such as when climbing stairs)
Feeling like one can’t get enough breath/air hunger
Pressure behind eyes
Nausea and no appetite
Exhausted/easy fatigue
Poor recovery after activity
Weak, esp. arms
Brain fog
Hot flashes/feeling hot
Calves cramp
Numbness in hands
Pale after walking


How to do I bring my low iron up?  Some patients like to try bringing up verified low iron by focusing on high iron foods. Foods rich in iron include lean meats, liver, eggs, green leafy vegetables (spinach, collard greens, kale), wheat germ, whole grain breads and cereals (though not for those with gluten problems), raisins, and molasses. You can also help yourself by cooking foods in a cast iron skillet. NOTE: if inflammation is high, you won’t be able to raise your iron. You’ll just keep driving ferritin up! Lower the inflammation first!

But many patients and their doctors have found it necessary to supplement with iron tablets, which includes those such as Ferrous Bisglycinate, and might also include Ferrous Sulfate, Ferrous Glutamate, Ferrous Fumerate, , etc. Another favorite are the whole food versions of iron which can be made from beet root or liver. Supplementation needs to be spread out during the day, with food, for better absorption, say some practitioners. In the first group above, Bluebonnet’s Ferrous Bisglycinate is a favorite among many patients since unlike the others, it causes less constipation.

If you take iron that causes constipation, patients add magnesium to tolerance to help soften stools.

Beware of liquid iron that is animal based (heme)–it may be the best absorbable iron, but it can blacken your teeth, as it did to the owner of this site. One suggested solution is to use a straw when taking the liquid iron. VEGETABLE BASED (nonheme) liquid iron avoids this, even if less absorbable. Also, because liquid heme iron is much more absorbable, patients take far less to achieve the same results as tablets. 

I was contacted by a physician practicing alternative medicine who highly recommends Floradix Iron and Herbs, or Enzymatic Therapy Liquid Liver. Check in your local health food store or pharmacy.  From Canada, there is a chewable non-constipating iron called Hemofactors by Natural Factors, and one patient who wrote me swears by it.  It’s Ferric Pyrophosphate, also called SunActive Iron and you’ll want to pay attention to the “elemental iron” amount to get enough.

How much iron supplementation do I need to raise my low levels, and how long do I take it?

Patients have discovered they may need 150 to 200 mg of  “elemental iron” daily, spread out with meals (i.e. 3 times a day), in order to adequately raise their iron levels. Always check your labels or call the company to see how much “elemental iron” is in each tablet.  It can a minimum of 6-8 weeks to improve your levels to the desirable goal. Keep track of labwork with your doctor to see where your levels are, because you want to lower the iron once you achieve your goal since iron promotes free radicals.  Some women who are menstruating may have to stay on maintenance amounts of iron.

Liquid is far more absorbable, so you may not need as much “elemental iron” as tablets. But it’s hard to know how much will raise your iron. Labs will help.

WARNING: literature states that if you have cancer, taking iron can promote cancer growth. Talk to your doctor before deciding this information is right for you.

Should I take anything with the iron to help? Yes, say patients, two things: an acid in the drink (lemon juice or apple cider vinegar, such as one tablespoon) and Vitamin C to tolerance each time.

Also taking a mineral supplement can assist the absorption, as can B12.  One important B-vitamin is Folate (not Folic acid), which promotes red blood cell formation. Adding it to your iron supplementation can be key.

What should I avoid in my stomach at the same time as iron? Avoid calcium, coffee, tea or wine (tannins interfere with absorption to some degree), the fiber of bran, and chocolate at the same time you take iron. Also avoid mixing iron with your thyroid pills. Keep them all 2-4 hours apart from each other.

Can I take iron at the same time I swallow my desiccated thyroid? If you swallow your desiccated thyroid instead of doing it sublingually, it’s important to avoid swallowing iron at the same time,  since the iron will bind to some of the thyroid hormones as they mix in your stomach and bind some of that NDT. Take your desiccated thyroid one hour before you take iron, or several hours later…or try your best to keep them apart somehow.  If you are doing your natural thyroid sublingually, some may end up still being swallowed and thus mixed with that iron, but we’re not sure how much of a problem that is…. So just use your best judgment.


What about the constipation I get from taking particular iron supplements? If you do find yourself with constipation or very hard stools, talk to your doctor about adding Magnesium Citrate as a supplement, taken twice a day, until you find the amount that softens your stool. You’ll know within a few days if the amount you are taking is enough….or even too much (i.e. too much will cause diarrhea).

What if I can’t tolerate oral iron? If you have problems absorbing oral iron due to a previous stomach surgery or other issues, another option is to use Venofer – an intravenous iron which helps replenish body iron stores.  Talk to your doctor.  Or, if iron supplementation gives you a headache, you may have to start on less than others, and slowly build up.

What about iron injections or IV? If your ferritin is in the teens, or your iron labs are seriously low, ask your doctor about either an iron injection or prescribing an IV iron infusion. Either will raise your iron levels far quicker—just a few weeks as compared to a few months from supplementation. The IV infusion does require being in a health facility and it can be expensive, but the plus of raising iron quicker is there. You will be monitored to prevent anaphylactic shock. Patients will often follow that up in a few weeks by staying in lower doses of oral iron tablets.


How soon do I re-test my iron labs when I’m supplementing iron?  Every 4-6 weeks minimum is best, say patients. You don’t want to overload yourself with iron, and some patients have had that happen when doctors make them wait too long! Or you could have hemochromatosis and not know it! Also, you could have what’s called the MTHFR genetic defect, which means your body doesn’t do a good job breaking metals down. Thus, your iron could get too high. ALWAYS retest, we have learned!

Once I get my iron levels back up, will it all stay up? For females, some of us have had our ferritin or iron levels plummet again, so it may be wise to stick with a small dose of supplemental iron or eat iron rich foods, especially if you are female and still menstruating. Once into menopause, your ferritin levels may stay where they need to…but they may not!


Can I raise my iron levels without being on iron?  Possibly…if you aren’t severely anemic, and are just not totally optimal! One thyroid patient reports that just by getting on NDT and finding her optimal amount, she saw her iron levels go to an optimal level. Others focused on consuming high iron foods. You can see where optimal iron results should be, here.

Are men different than women in their iron lab results? Yes. Men normally have higher levels of iron and ferritin than women without having an infection. It’s common to see healthy men with a ferritin slightly over 100. See the lab values page.


My TIBC is low as is my iron. What does that mean for me? TIBC stands for Total Iron Binding Capacity, and it’s basically telling you how much protein your liver is making in order to envelope and carry that iron around. Typically, if iron is low, TIBC will be higher in the range. So if your TIBC is low, it means three things 1) Your liver needs support! Milk Thistle and Dandelion Root are two supportive supplements. 2) You can’t take the high amounts of iron that others do with low TIBC, since it will be problematic without that protein 3) You’ll need to consider taking lactoferrin with each dose of iron to supply the needed carrying iron. Because of lactoferrin, you can take the higher amounts.

What if I find my ferritin AND other results are super high? This is called an iron overload, such as the inherited disorder called hemochromatosis.  Your doctor will usually direct you to give blood in order to lower these harmful higher levels. With hemochromatosis, you can have a low TIBC or UIBC. (Another cause of high levels of iron is having a defect in the MTHFR gene, but it will usually mean low ferritin, too).

What causes low ferritin when other labs look great or are even too high? That usually points to an MTHFR mutation and having high heavy metals. You can also see high levels of homocysteine with this defect, as well as higher levels of copper and other metals.

DIDN’T DO YOUR PERCENT SATURATION LAB?? If you did both TIBC and Serum iron, you can figure out your percent saturation right here.


Need a good doctor to work with in all this? Go here.–

Get your own iron labs ordered and done via the Recommended Labwork page

You can read more about low iron and thyroid here:

*Iron and selenium deficiencies on iodine and thyroid metabolism found here.

*Iron Deficiency in Goitrous Children article found here.

*Iron Supplementation for Unexplained Fatigue in Non-Anaemic Women article found here.

*AS FAR AS THE 70-90 RANGE FOR FERRITIN: there were five scholarly articles on the net referring to this 70-90 range from 2004 to 2012…but they have all disappeared i.e. the websites disappeared from the net. So most of what you will see on the internet are websites which saw this range HERE on Stop the Thyroid Madness (and fail to give STTM credit), and we at least had studies or articles to prove it. Now we don’t.

*A good article explaining supplements to take with iron found here.

Additional reading:

*Details on iron:

*How low iron affects cortisol:

*Impaired conversion of T4 to T3:

*Low iron and sympathetic system: