Bromine and Your Thyroid

This post is partially adapted from a chapter in my Essential Thyroid Cookbook Lifestyle Companion Guide. It’s a free download for those who own our #1 best selling Essential Thyroid Cookbook.

This post received some major updates on May 26, 2023.

When it comes to optimizing thyroid health, it’s easy to focus on some of the common factors that influence thyroid hormone output, such as sound nutrition, adrenal support, maximizing thyroid hormone conversion (T4 to T3), balancing blood sugar, and getting plenty of fiber, to name a few.

For those with Hashimoto’s (autoimmune hypothyroidism, which well over 90% of people with hypothyroidism have), these factors can include abstaining from gluten, healing the gut, and being mindful of endocrine/hormone disruptors, including reducing toxic body burden, to name a few.

What many don’t realize is that there’s a commonly-found endocrine disruptor that’s one of the biggest thyroid offenders—bromine. And when I say “commonly-found,” I do mean common.

Bromine is a halide that competes for the same thyroid gland receptors that uptake iodine, interfering with thyroid hormone production and often resulting in hypothyroidism.

And we know how important iodine is for thyroid function. The thyroid’s job is to absorb iodine and combine it with the amino acid tyrosine. It then converts this iodine/tyrosine combination into T3 and T4.

[Go here for my 2-part series, Your Thyroid + Iodine: 1, 2]

Halides are chemical components of halogens—iodine is part of the halogen family that includes bromine, chlorine, and fluorine. These halides are similar enough to iodine that our thyroid will absorb them. They then accumulate, displacing iodine. So even if you’re getting adequate iodine intake, which many of us aren’t, you can’t use it. It’s referred to as the Bromine Dominance Theory.

Common sources of bromine include:

  • Brominated fire retardants (found in some carpet padding, mattresses, cars, and electronics)
  • Insecticides and pesticides, especially methyl bromide, used primarily on strawberries
  • Plastics: especially in computers
  • Commercial flours, including commercial baked goods in the form of dough conditioner (potassium bromate)
  • Soft drinks, especially Mountain Dew and other citrus-flavored sodas (brominated vegetable oils)
  • Some medications, including some inhalers and nasal sprays, ulcer medications, and anesthesia agents
  • Some pools and hot tubs (bromine gas)

Highlight: flame retardants
Polybrominated diphenyl ethers, or PBDEs, the organobromine compounds used as flame retardants, have been banned in Europe, but not in North America. They’re found in mattresses, pillows, upholstered furniture, carpet padding, building materials, and electronics, which we’re exposed to through not only direct contact, but also dust.

Brominated flame retardants (BFR) have replaced some PBDEs, but they still carry endocrine-disrupting risks because they accumulate in fatty tissue and act as an estrogen-mimicker, which is a risk for all of us…women, men, and children. (It’s always a good idea to avoid any estrogen mimicker.)

Children are especially sensitive to flame retardant chemicals and levels in toddlers have been shown to be three times higher than their mothers. Needless to say, many parents have come to realize that using flame resistant pajamas for their kids isn’t worth the risk. (Flame retardants were added to children’s pajamas and other clothing when smoking was a primary cause of fires, but fewer people smoke nowadays and the majority of homes have smoke detectors.)

I don’t like alarmist tactics, but the health implications of flame retardant chemicals are nothing short of staggering. Many studies have linked them to:

Some studies suggest that exposure to PBDEs lowers TSH (thyroid stimulating hormone) during pregnancy, which can have implications for maternal health and fetal development.

According to the Environmental Working Group, “PBDEs are found in the bodies of nearly every American. Laboratory studies show that exposure to minute doses of PBDEs at critical points in development can damage reproductive systems and cause deficits in motor skills, learning, memory and hearing, as well as changes in behavior. In addition, they persist in the environment and therefore bioaccumulate in people.”

In his now-archived article, Flame Retardant Causes Altered Thyroid Hormone Levels, Dr. Joseph Mercola stated, “The U.S. implemented fire safety standards in the 1970s that over time has led to more and more products adopting the use of PBDEs to meet the stringent regulations. For example, as of July 1, 2007, all U.S. mattresses are required to be so flame retardant that they won’t catch on fire even if they’re exposed to the equivalent of a blow torch!”

In my mind, the biggest PBDE offender is commercial mattresses, given that we spend one third of our lives in bed. There are now many eco/green mattress companies. I don’t have a recommendation at this time—I purchased three wonderful organic mattresses a few years ago from a company that has now, unfortunately, gone out of business. I’m not going to make a recommendation—or make money from an affiliate link—when I haven’t tried something myself.

How to minimize bromine exposure:

  • Go organic as often as your pocketbook will allow.
  • Shop for non-brominated products, especially mattresses, which are one of the worst offenders, again, given that we spend a third of our lives in bed.
  • Trade your soft drink for mineral water with a little fruit juice.
  • Steer clear of commercial bakery products, which is easy when you’re gluten-free. 
  • Keep your home as dust-free as possible.
  • Filter your air.
  • Use a quality vacuum cleaner that does a good job at trapping particles.

How to excrete bromine and generally detox the body:

  • Support liver function to reduce your overall toxic load.
  • Ensure that your iodine levels are adequate and increase your Vitamin C intake.
  • Take epsom salts baths.
  • Sweat in a sauna.
  • Take clinoptilolite (natural zeolite). This is one of my STRONGEST recommendations for detoxing any contaminant from the body. Read more here about general zeolite benefits. And read more here for more about the specific zeolite product I highly recommend. 

While we live in a world where it’s impossible to steer clear of all toxins and endocrine disruptors, your best defense is offense. I realize that switching out a mattress can be a big expense. If your mattress is relatively new and it’s too soon to scrap it, you can minimize the toxic exposure by encasing it inside an organic, waterproof cover. Not plastic! To add another layer of protection, put an organic topper on your mattress.

Additionally, you don’t have to buy an in-home sauna (although I do have a mini sauna and love it)—many gyms have saunas. 

In the end, I feel that keeping bromine exposure to a minimum is pretty straightforward. All of the other recommendations listed above are relatively simple.

Let’s keep that iodine where it needs to be—in the thyroid gland!



You mentioned that you have a mini sauna - Is it an infrared sauna? If so, could you share a link for the sauna? I've been loving going to my sauna therapy appointments but would much prefer to have something at home. Thank you!

Yes, I have the one from SaunaSpace. 

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