Are Low Iron Levels Sabotaging Your Thyroid Hormones?

Low iron thyroid

Iron Basics
Low iron is one of the most common things I see in women who walk through my door. It’s also one of the most common tests we run and we do this by looking at ferritin levels (a measure of iron stores in your body). The normal reference range for ferritin is anywhere from 10-291 ng/mL for women. Most often, if you’re not clinically anemic and your ferritin is within this range, you won’t be alerted to abnormal ferritin levels (even if they as low as 12, for example). However, recent studies show that women have improved energy and feel best with ferritin levels > 50, even if they’re not anemic.

Symptoms of Low Iron
Symptoms of low iron can include fatigue, low energy, hair loss, feeling cold, weak or brittle nails, palpitations or shortness of breath, brain fog and more. Many of these symptoms are also symptoms of low thyroid function or hypothyroidism. If you’ve been previously diagnosed with hypothyroidism and are still experiencing many of these symptoms, take the guess work out and have your ferritin levels checked.

Side note: If you experience heavy menstrual periods, are vegan/vegetarian, or have digestive disorders (such as celiac disease) that affect nutrient absorption, it’s also important to have your ferritin assessed on a regular basis.

The Iron-Thyroid Connection
Women are more likely to have low iron levels and we’re also more likely to have hypothyroidism or Hashimoto’s Disease (Lucky us!). We don’t usually think of iron as being essential to thyroid function, but it is!

Our thyroid needs adequate iron levels to produce the active hormones T4 and T3. If our body is low in iron, the enzyme responsible for this can be reduced in activity up to 50%. Iron is also essential to another key enzyme, which converts T4 into T3. (T3 is our most active thyroid hormone). If you are already on medication for your thyroid (such as Synthroid) having adequate iron levels is still important for converting the medication into active, usable, thyroid hormone.

There’s more: a very common symptom of hypothyroidism is low stomach acid, which decreases our ability to break down foods and absorb nutrients. Thus, a very common symptom of hypothyroidism is (you guessed it) low iron levels!

Low iron –> hypothyroidism –> low iron –> vicious cycle

So What Should My Ferritin Be?
For optimal energy and thyroid function, ferritin levels should be at or above 80 ng/mL. Hair loss or thinning can occur at levels less than 40. Anything below 30 is what I call “scraping the bottom of the iron bucket”. If your ferritin is really low, your thyroid won’t be functioning properly no matter what other medications or supplements you are taking. Most women I test ferritin levels on are somewhere between 20-50, and many are in need of some sort of iron support or supplementation. If you’ve been on iron in the past and have experienced digestive upset, constipation, or nausea, there are better supplements out there that don’t have these unwanted side effects and are more effective in bringing up iron levels.

That said, we also don’t want too much iron, as this can be harmful to the body. So supplement wisely and make sure to re-test your levels on a regular basis.

The Recap: 

  • Many symptoms of iron deficiency and hypothyroidism overlap. What you thought were low thyroid symptoms (such as fatigue and hair loss) could in fact, be due to low iron!
  • Your thyroid requires adequate iron levels for TWO key enzymes that are vital to hormone production and activation.
  • If you have low thyroid function or hypothyroidism, have your ferritin levels assessed and get a copy of the results. Use 80 ng/mL as a guide to optimal levels, although different people feel best at different levels.
  • Ask your Naturopathic Doctor about testing your ferritin levels and if needed, the best iron supplements to increase your levels quickly without causing you digestive upset.

Want more info on the thyroid tests you need? Check out my last blog post here

Take care!

Dr. Katie



Why you should have a physical exam

There seems to be a trend forming amongst some MD’s.  They say that unless you have an indication of a disease, a physical exam is not necessary until the age of 40.

So one of my patients had been off anti depressants for some time and she was feeling like her energy was low and she just wasn’t quite ‘right’.  When she asked her MD for some blood work and a physical he said that it wasn’t needed until she was 40.  He would happily give her a new script for her depression as that was likely why she was feeling low.

While my patient is quite comfortable with the idea that she may need anti-depressants again, she wanted to be sure that it wasn’t something else first, so she came to see me.

After I did a physical exam and routine blood work based on her history (at LifeLabs), we discovered that she is anemic, has low vitamin D status and has low testosterone levels.

This is an example of where naturopathic doctors can fill in the holes our health care system has.

Why IV therapy?

I’ve been doing IV therapy for a number of months now with great success.

Here we have a mini-video on IV treatments, to see it click here: Whitney discussing IV Therapy

I have been seeing quite a few patients with a number of disorder who are all benefiting from IV vitamin and nutrient therapy. They include people with fatigue, Crohn’s, collitis, migraines and anemia.

Please give us a call or send a message if you would like more information about IV Therapy.



Saliva Hormones Help Determine Herbs

One of my patients came in recently feeling sluggish, tired, emotional and with signs of hypothyroidism. Discussing a patient’s case fully is often enough to put me on the right path of treatment but I also find testing to be extremely helpful in determining exactly what is going on.

We decided to order a Thyroid blood test to show her levels. In naturopathic medicine we deal a lot in the grey areas and use a term called subclinical hypothyroidism where it’s not quite at the level of treating with pharmaceutical grade synthroid but may be addressed using herbs, diet and supplements. This is why its important to see the numbers on reports.

Her blood work came out fine. Then we turned to saliva hormone testing. Here is an example of a report we might get back: 


Her results came back as low cortisol. This was extremely helpful as some herbs used in adrenal formulas can decrease cortisol even further. I wouldn’t want to prescribe something that normally would be very helpful for most people but in her case, might make things worse.

Testing can sometimes get expensive but it is really helpful for the practitioner to measure what’s going on and then track it in the future to see your progress. Then you can literally see how you are improving.

As my favourite Scottish Reflexologist used to say, “If you don’t take care of your body, where are you going to live?”