The 6 Worst Thyroid Disruptors Hiding in Your Home + How to Eliminate Them:
The thyroid is an endocrine gland located in the neck. It uses iodine, tyrosine, selenium and other nutrients from the foods you eat to make two main hormones: Triiodothyronine (T3) + Thyroxine (T4). These hormones are critical to your overall health because they regulate the body’s metabolism, digestive function, mood and energy. A well-functioning thyroid is also critical for fertility and hormonal balance, since thyroid output is closely linked to female reproductive health.
Unfortunately, hypothyroidism is becoming exceptionally common in my practice with hundreds of new cases diagnosed in my practice in past 5 years. While genetics can play a role, thyroid issues may also be triggered by seemingly innocent everyday products hiding out in your home. From toxic personal care products, to environmental pollutants I always urge my hypothyroid + Hashimoto’s patients eliminate following 6 thyroid disrupting chemicals from their homes ASAP:
A recent study, published in the Journal of Epidemiology found that exposure to perfluoroctanoic acid (PFOA) led to higher instances of thyroid disease. Researchers compared blood levels & exposure with incidence of thyroid problems and definitively concluded that exposure to PFOA was associated with thyroid problems. PFOA are fluoride-containing chemicals that make house hold objects and foods stick & stain-resistant. Along with thyroid disease PFOAs have also been linked to cancer, infertility, birth defects, and weaker immune systems. Here’s where they could be hiding out in your home:
- Non-Stick pots & pans: Most conventional pots & pans are coated in PFOAs to prevent your food from sticking while you cook. Replace any non-stick cookware (especially those with scratches, which causes the release of even more of them chemicals) with cast-iron, enamel, glass, or stainless steel pots and pans.
- Dental Floss: Many companies add non-stick chemicals to your dental floss in order to make it glide more easily between teeth. I’m definitely not advising that you give up flossing – it’s important to your health and has been linked with better fertility and a longer life. Instead, choose a natural dental floss like this one.
- Microwavable Popcorn: PFOAs can be found lurking inside bags of your favourite movie night snack since it prevent the grease from the popcorn from leaching through the bag. Add heat to these chemicals via microwave and you’re left with an even worse thyroid disruptor. Instead of purchasing microwavable popcorn try making your own at home using an air popper. We use this machineto pop organic kernels & top our popcorn with a little organic cold pressed olive oil, Maldon sea salt and a bit of nutritional yeast for a delicious move night snack.
- Personal Care Products: Some shampoos and body lotions contain these thyroid-disruption chemicals. Check ingredient labels for anything beginning with the word ‘perfluoro’ and toss these products pronto.
My patients are often surprised to learn that the thyroid gland is one of the most fluoride sensitive tissues in the body. This is due to the fact that fluoride is structurally similar to the thyroid critical nutrient, iodine. Iodine and fluoride are both halogens, they have similar molecular sizes & structures, and are found right next to one another on the periodic table. Due to these similarities high amounts of fluoride from your tooth paste and drinking water can displace iodine in the thyroid and lead to thyroid disease. We need adequate iodine levels to make thyroid hormones, and there’s a consistent body of animal & human research showing that fluoride worsens the impact of an iodine deficiency. Studies also found that fluoride negatively impacts TSH and free thyroid hormone levels, even when you’re exposed to the accepted ‘safe’ concentration of less <0.5 mg/L. Fluoride has also been shown to impact thyroid health in the following ways:
- Fluoride inhibits T4 to T3 conversion by interfering with deiodinases enzymes that convert T4 to T3, leaving you with less biologically active T3. T3 is important for your metabolism and energy production and fluoride exposure can lead to under diagnosis of hypothyroidism since TSH (the marker your GP uses to screen for thyroid disease) may look normal even when T3 levels are suboptimal.
- Fluoride disturbs the balance between reverse T3 (rT3) and T3. rT3 is created by the body under times of stress and due to various chemical exposures. It looks structurally similar to T3 and will bind thyroid hormone receptors but will not activate them. rT3 is another common reason for under diagnosis of thyroid disease, which is why it’s important for your doctor to run a full thyroid hormone panel.
- Research shows that fluoride increases the concentration of TSH (thyroid-stimulating hormone), and decreases free thyroid hormone levels. Prolonged fluoride exposure can even shut down thyroid gland function.
You can decrease your risk of thyroid disease by simply swapping out that fluoridated tooth paste for a natural brand and by filtering your drinking water. Our current favourite natural tooth paste is by designs for health. It’s fluoride-free and contains probiotics to improve the balance of good bacteria in your mouth. We use this water filtration system at home and are saving up for a whole home reverse osmosis water filter. It’s also a great idea to have your iodine levels tested by your ND since adequate iodine intake has been shown to mitigate some of the negative effects of fluoride exposure.
PCBs are a group of human-made chemicals that were largely banned in the 1970s due to environmental concerns. Unfortunately, PCBs are chemically stable so around 10% of those produced still exist in our environment and food supply. Before the ban, companies using PCBs were dumping them into the water where they made their way into the soil used to grow our food and feed farmed animals. PCBs are fat soluble, meaning that they’re stored in fat cells. Once the PBCs accumulate in animal cells they remain there for a long time and can even be transferred to babies through a mother’s milk. The main sources of PCBs come from our diets with research indicating the top three sources are meat, fish, and eggs.
PCBs are problematic for thyroid health because they act like hormones and confuse our bodies into mistaking them for hormones. They bind to hormone receptors where they can interrupt normal hormonal function. Studies show that they specifically impact the thyroid by reducing the concentration of thyroid hormones in our bloodstream. You can reduce your exposure to thyroid-disrupting PCBs by following these simple dietary recommendations:
- Avoid farmed salmon and other commercially produced fish, which are found to have the highest levels of PCBs.
- When preparing fish remove the skin; this will reduce your exposure to PCBs and other toxic chemicals that have accumulated in fatty skin tissue. Fish are an excellent source of nutrients including omega-3 fatty acids and vitamin D, so don’t remove fish from your diet – just be selective about the fish you eat.
- Choose lean cuts of meat and purchase organic whenever possible. PCBs are concentrating in fatty tissue so leaner cuts of meat will naturally contain less fat-soluble toxins.
- Limit your dairy intake as PCBs have been found in high amounts in cow’s milk. Non-dairy alternatives like organic almond milk, coconut milk and nut cheeses are a safer bet for your thyroid.
- When it comes to safe sources of PCB-free eggs, my best advice would be to raise your own backyard hens. Keeping chickens allows you to control the quality of food and water that your chickens are exposed to leading to lower levels of toxins accumulating in their eggs. If backyard chickens are not a possibility then you can reduce exposure by serving your eggs with a side of veggies. Studies of PCB exposure show that foods like vegetables, mushrooms and seaweed reduce your absorption of PCBs.
According to the Stockholm Convention on Persistent Organic Pollutants, 9/12 most dangerous and persistent pollutants are found in pesticides. One of the primary reasons that pesticides should be avoided in patients with thyroid disease is because so many of them interfere with thyroid hormone metabolism. Pesticides also interfere with thyroid hormone conversion, interrupting your ability to convert T4 into bioactive T3. Not only do they directly impact the thyroid gland, they also have indirect effects on your endocrine system since many are also considered xenoestrogens; synthetic compounds that mimic estrogen in the body. These xenoestrogens raise your own estrogen levels and high estrogen can lead to lower thyroid hormone levels.
Pesticide exposure is also linked to an increase thyroid gland size (aka goiter) as well as increase rates of autoimmune thyroid disease. Autoimmunity is the leading cause of thyroid dysfunction in North America and studies show a link between increased pesticide exposure and higher levels of the TPO thyroid antibodies that cause autoimmune hypothyroidism. If you’ve been diagnosed with hypothyroidism it’s essential that you have your antibodies tested to determine if your thyroid dysfunction is due to an underlying autoimmune disease. When a patient tests positive for TPO antibodies I immediately put them on an organic only diet to limit pesticide exposure. Not only do they feel better when eating whole, organic foods, I also see a trend in lowered antibody levels in my patients when they switch to an organic, low pesticide diet.
BPA is everywhere in our environment. It’s likely found throughout your house in the form of plastic water bottles, plastic bags, Tupperware containers and in the lining of canned foods. This is bad news for your thyroid gland. A new large scale study confirmed the link between plastics like BPA and thyroid hormone levels and found that BPA displaces active T3 from thyroid hormone receptors.
BPA can bind to the thyroid hormone receptors, which are present on all the cells in human body, and block thyroid hormone function. It is also shown that these plastics can increase TPO antibody levels leading to higher rates of autoimmune diseases. Unfortunately for your BPA-free plastic water bottles, emerging evidence tells us that BPA-free plastics are just as harmful as their BPA-filled counter parts. Your best bet is to eliminate plastics all together and never ever heat up food in a plastic container. These are my top tips for eliminate plastics from your life:
- Replace plastic Tupperware with glass, metal or good old fashioned mason jars. These are the ones we use at home.
- Toss plastic water bottles and instead grab a glass or stainless steel version. My favourite glass bottle comes from a company called BKR, and the stainless steel swell bottles are a great economical choice as well.
- Purchase a glass or metal straw + a travel cutlery set to avoid plastics while dining out at restaurants. We also always bring out our own glass Tupperware containers to carry out leftovers.
- Buy bulk! Bring a bunch of mason jars to your local bulk barn or health food store and stock up on plastic-free foods and cleaning products. Not only is this better for the environment but it also reduces your exposure to plastic containers.
- Say no to the receipt – sales receipts are a significant source of BPA. Simply ask the cashier to toss it (and please wear gloves at work if you are said cashier) or ask for an emailed copy of your receipt instead.
- Switch to organic & all natural beauty products. Most conventional skin care and make up is full of phthalates; a thyroid-disrupting plasticizer (see below).
Phthalates are chemical compounds that can be found in plastics and many common household products. DEHP is a particularly worrisome form of phthalate that is found in personal care products, medical devices and even your food. A new study linking DEHP to thyroid disease found a strong relationship between thyroid disease and this common plasticizer. In this study, urine samples were analyzed for phthalate levels and researchers observed that exposure to DEHP was associated with as much as a 10 percent decrease in certain thyroid hormones. These latest results were consistent with findings from previous smaller studies finding that higher concentrations of urinary phthalates & BPA were associated with greater impacts on thyroid hormone levels.
You can reduce you phthalate exposure by switching to all-natural and organic personal care products. It can be costly to replace all of your favourite makeup and skin care products all at once so I recommend that my patients replace their beauty products slowly as they run out of their usual makeup and moisturizers. Websites like the detox market and Environmental Working Group can be wonderful resources when switching over to natural phthalate-free products. It’s also important to get rid of those plastic food containers and water bottles asap as they’re a common source of endocrine disrupting phthalates.
If you live in the GTA and want to help developing your own personalized thyroid health protocol you’re welcome to book in for an initial consultation or contact me via my website for additional information.
*Note: online services provided by Dr. Sarah to those of you living outside of Ontario are delivered as a Certified Functional Medicine practitioner consult and not as an Naturopathic doctor appointment & as such they will not be eligible for reimbursement through private insurance.
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- Goldner WS, et al. Pesticide use and thyroid disease among women in the Agricultural Health Study, 2010
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- O’Brien E, et al. Perinatal bisphenol A exposures increase production of pro-inflammatory mediators in bone marrow-derived mast cells of adult mice, 2014
- Susheela AK, et al. Excess fluoride ingestion and thyroid hormone derangements in children living in Delhi, India, 2005
- UNEP. Ridding the world of POPs: A guide to the Stockholm Convention on Persistent Organic Pollutants, 2005
- Zhan XA, et al. Effects of fluoride on growth and thyroid function in young pigs, 2006
- Zoeller RT. Polychlorinated Biphenyls as Disruptors of Thyroid Hormone Action. PCBs: Recent Advances in Environmental Toxicology and Health Effects, 2001
This information is not intended as a substitute for the advice provided by your Naturopathic doctor or primary care physician. Do not use the information in this document for diagnosing or treating a health problem or disease. Always speak with your Naturopathic doctor before taking any medication or nutritional or herbal or using any treatment for a health problem. If you have or suspect that you have a medical problem, contact your health care provider promptly. Do not disregard professional medical advice or delay in seeking professional advice because of something you have read online.