Your Thyroid + Calcium

This post is the first installment in my ten-part Minerals and Your Thyroid series, where I’m highlighting eight thyroid-supportive minerals (iodine is two parts) and one troublemaker: fluoride.

Calcium symbol: Ca
Atomic number: 20

Calcium is the most abundant mineral in the human body.

According to Dr. Richard Shames, calcium is “absolutely essential” for proper thyroid function. In his book, Thyroid Power, he also states that calcium deficiency is a “related condition” to low thyroid function.

[I thoroughly address optimal thyroid nutrition in my best selling cookbook, The Essential Thyroid Cookbook: Over 100 Nourishing Recipes for Thriving with Hypothyroidism and Hashimoto’sThe educational component of the cookbook details not only thyroid-supportive minerals, but also vitamins and amino acids that help to optimize thyroid function. The mouthwatering recipes are chock full of these supportive nutrients.]

Additional things to know about the thyroid/calcium relationship are:

  • Proper thyroid function helps to regulate blood calcium levels.
  • Hypothyroidism can inhibit calcium metabolism.
  • Thyroid hormones directly influence calcium absorption in the digestive system.

In addition to supporting bone health, adequate calcium also helps to regulate our acid/alkaline balance and supports muscle and nerve function.

There is quite a bit of controversy around supplementation.

Firstly, given my mom’s history with advanced osteoporosis, I learned many years ago that supplemental calcium needs a carrier – magnesium or Vitamin D. Or ideally, both.

(Aside from Vitamin D being a carrier, adequate levels of D will help with calcium absorption.)

I no longer recommend calcium supplementation. This may surprise you, given that thyroid hormone replacement is said to lead to bone loss. (This is another highly controversial subject that isn’t fodder for this post.)

It’s also known that unmanaged/undiagnosed low thyroid function is a leading cause of osteoporosis. So you’d think I’d be recommending calcium supplementation left and right, right?

Supplemental calcium, especially with without a carrier, can do bad things. Really bad things.

It can settle into your joints and soft tissues such as your heart and arteries. Any deposits into the joints can cause arthritis.

And it incites a false sense of security. Like, “Hey, I’m taking my calcium, so I don’t have to worry about osteopenia or osteoporosis.”

But you do need to take care of your bones beyond popping a pill. Supplemental calcium isn’t a panacea.

If you’re still not convinced, my friend and colleague, Irma Jennings, sums things up nicely here.

With this comes a short personal story. Several years ago, I started getting pounding heart palpitations out of nowhere. I was sleeping well, I wasn’t particularly stressed, and I wasn’t drinking much caffeine at all.

One afternoon, I was in a casual meeting with colleagues. We were laughing and hamming it up and all of a sudden, I could feel my heart racing – into my throat. My whole chest cavity and neck were pounding like a bass drum.

I started to freak out. There was no pain, but I thought I was having a heart attack. I said, “Someone take me to the emergency room.”

The tech did a bunch of testing, including a treadmill stress test, and everything was fine. Better than fine.

After all of the assessments, the ER doctor sat me down and asked me if I was taking any calcium supplementation. I said, “Yes, I just started taking a cal/mag about two weeks ago.” He said, “Stop taking it. Even when you’re taking it with magnesium, supplemental calcium can cause major heart palpitations.”

I of course stopped taking it and I haven’t had the palpitations since.

I recently had a client with “unstoppable” heart palpitations. Sure enough, she was taking calcium supplementation (with no carrier). I suggested she stop and poof, palpitations gone.

Focus on Food
We’ve been browbeaten into believing that dairy is the best food source of calcium. Not true.

The best food sources of calcium are: sardines, collard greens, spinach, turnip greens, mustard greens, beet greens, bok choy, Swiss chard, kale, broccoli, cabbage, green beans, sauerkraut, kimchi, sesame seeds, almonds, chia, amaranth, millet, blackstrap molasses, cinnamon, garlic, basil, oregano, thyme, sea vegetables, tofu prepared with calcium sulfate*, tempeh, natto, miso, and yes, yogurt.

* I’m not a fan of tofu. I’m not categorically against soy, but I believe it should be fermented, as in tempeh or natto, and only consumed in moderation.

If you’re unable to get what you need from the above list of food sources and you feel that supplementation is warranted:

  • Take no more than 500 mg of elemental calcium at one time to maximize absorption.
  • If you’re taking thyroid hormone replacement, be sure to allow at least six hours after taking your meds before taking any calcium supplementation.
  • The dose most commonly recommended is 1200 – 1500 mg/day. But Dr. Thomas E. Levy, author of Death by Calcium, states, “If you’re over 36 years old, you only need 200 to 300 mg of calcium per day. Not the 1,300 mg the government recommends.” (This is clearly less than the above-mentioned “500 mg at a time.”)

Important note for this whole Minerals series: You may see some slight discrepancies in the list of foods in this post and the list of foods in my thyroid- and immune-supportive nutrition chart (which you can download for free here). This is because for the chart, we created a ranking system. If each thyroid- and immune-supportive food didn’t have a broad enough nutritional spectrum such that it represented enough nutrients, it didn’t make the cut. In other words, the list in this post may be slightly more inclusive.


Great info and timely for me.  I started having heart palpitations and insomnia about a month after starting a calcium/magnesium supplement for nerve and muscle vibrations and twitches in my feet and legs.  It helped for the vibrations, but I switched to a much lower dose(175 CA with vit D/K2).  Heart palpitations are decreasing but still there, so I will stop taking.  I thought that many vegetables, like spinach and grains contain oxalates or phytates which bind the calcium and is therefore not well absorbed.  Wondering your thoughts about this.  Great article!!

I take strontium 680 mg 2 hrs. apart of Calcium Plus (powder w/D3 and Mag) as I am hypothyroid and Hashimoto and have osteoporos. I doubt I can eat more than 1 or 2 svgs. a day of your preferred foods.  Do you  think I should stop the CA. Does the strontium replace need for CA?

Thank you.



OMG!  This describes exactly what happened to me!!   Thank you so much for solving yet another mystery for me with my supplements; i have had more than one problem occur with supplementation.  So many side effects even with OTC vitamins and minerals it seems especially with hypotyroidism.  I would presume because we metabolize so much slower that a normal thyroid? 

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