The American Thyroid Association (ATA) estimates that five to eight women are affected with Hashimoto’s for every one man. The ATA also estimates that one in eight women will be affected with Hashimoto’s or another thyroid disorder at some point in their lives.
I wanted to share a post this week that will hopefully offer some insight and hope for women with autoimmune thyroid disorders.
I often get questions from my readers about why women have higher rates of Hashimoto’s and autoimmune disease. After all, I teach that Hashimoto’s is partly triggered by our environment, and men and women live in the same world, right?
Most autoimmune conditions do have a higher incidence rate in women as compared to men. These conditions include systemic lupus erythematosus (SLE), Sjogren’s syndrome, primary biliary cirrhosis, rheumatoid arthritis, multiple sclerosis, and Hashimoto’s. 
In this article, I wanted to explore a very important element of women and autoimmune disease that most researchers have not figured out — I think I’ve cracked the code!
Let’s take a look at:
- Theories about why women experience more thyroid disease
- What triggers Hashimoto’s
- How our immune system protects us
- The Izabella Wentz Safety Theory
- How to make our bodies feel “safe” again
Theories on Women and Autoimmunity
There are multiple theories as to why women are statistically more likely than men to develop autoimmune diseases in general, and Hashimoto’s in particular.
Theory #1: Hormones
Female hormones are thought to play a role in the development of autoimmune thyroid conditions. Pregnancy, puberty, and perimenopause (periods of major changes in female hormones) are three of the most common times in a woman’s life for the onset of thyroid disease to occur. 
Sex hormones, especially estrogen and prolactin, have an important role in modulating the immune system and may impact autoimmune disease. Estrogen can also change the requirements for thyroid hormone, and this may result in an autoimmune condition, especially in the presence of nutrient deficiencies. Prolactin, released by breastfeeding women to promote milk production, may also become elevated in women with Hashimoto’s (even when they’re not breastfeeding), and has been tied to both increased thyroid antibodies and infertility. 
Women have a higher risk of developing Hashimoto’s and Graves’ disease in the years following giving birth. One theory called “fetal microchimerism” proposes that this is due to fetal cells that may remain in the mother’s thyroid gland, which can cause an immune system response. 
A study of women with Hashimoto’s once revealed that 50 percent of them had fetal cells in their thyroid glands.  However, a 2015 study found that fetal cells in the thyroid gland postpartum were actually more common in women without autoimmune thyroid disease, and that they seemed to serve a protective role in preventing the development of Hashimoto’s and Graves’ disease.  (Isn’t that sweet? it’s like our babies are trying to help their mamas out — even in utero!)
So, hormonal differences and pregnancy don’t fully explain the higher rates of thyroid conditions in women.
Theory #2: Personal Care Products
Another theory to explain the different rates of autoimmune disease between the sexes is the fact that women use more personal care products than men. Sadly, conventional personal care products are laced with toxins. It is estimated that women use 12 products and are exposed to 168 chemicals from these products each day! Meanwhile, most men use just six products containing some 85 chemical ingredients. 
The skincare ingredients get absorbed into our skin, which is an excellent delivery system for chemicals. In fact, many topical patches and creams are used to administer pharmaceuticals and hormones directly into the bloodstream (think the Ortho Evra® birth control patch).
When products (food or drugs) are ingested, the liver usually works to make them less toxic before they enter the circulation. This is known as the first-pass effect, and only a small percentage of the original product may wind up in the circulation system.
By contrast, products applied to the skin, bypass the liver and go directly into the circulation, potentially producing systemic effects, until they arrive at the liver and are eliminated.
Endocrine-disrupting chemicals that are applied directly to the skin (such as those found in personal care products) can induce estrogen dominance, and thus, worsen or perpetuate autoimmunity.  The same applies when using soy products that induce estrogenic activity. The use of lipstick, in particular, has been connected to the development of lupus, another autoimmune condition. 
In my own case, I suffered a flare-up of Hashimoto’s from makeup I used in 2014. I have toxicity labs and a third-party test to prove the source of my contamination. So, I do think the use of endocrine-disrupting chemicals plays a role in the development of autoimmunity.
But I don’t think personal care products fully explain the higher rates either.
Theory #3: Genetics
Genetics do help us understand why Hashimoto’s tends to run in families, as there is a genetic predisposition to developing the condition.
Hashimoto’s thyroiditis can occur in two varieties:
1) An organ wasting (atrophic) form associated with HLA-DR3 gene inheritance
2) An enlarged thyroid (goitrous form) through HLA-DR5 inheritance
However, studies have shown that in people with Hashimoto’s, only 50 percent of their identical twins presented with thyroid antibodies, meaning genes alone are not the single defining factor, and environmental triggers play a critical role.  Intestinal permeability (leaky gut), as well as an environmental trigger, must also be present for the condition to present itself.
Research is well-established regarding the environmental factors that can trigger Hashimoto’s in those who are genetically predisposed. These factors include excessive iodine intake, bacterial and viral infections, hormonal imbalances, therapy with certain types of medications, and exposure to chemicals and toxins. 
The tragic Chernobyl incident is one example of a chemical-related environmental trigger.
Interestingly, a 1997 study of children exposed to the nuclear fallout from the Chernobyl explosion, found that 80 percent had thyroid antibodies, while only 17 percent of genetically similar children in a Ukrainian village that was at a further distance from Chernobyl, had the antibodies. These antibodies were found in boys and girls alike. 
So, while genetics do play a role, clearly environmental factors are more impactful in determining who develops thyroid conditions.
So, What Triggers Hashimoto’s?
While I believe there is some merit to each of the theories above, they don’t give us the full picture of why Hashimoto’s develops in the first place.
Through my research and work with people with Hashimoto’s, I have found that a combination of nutrient depletions, food sensitivities, an impaired stress response, an impaired ability to get rid of toxins, intestinal permeability, and infections, can trigger Hashimoto’s.
What do all of these things have in common?
All of these factors send a message to our body that the world we are living in is not a safe place, and that the body should go into an energy-conservation mode.
In 2014, I attended a lecture by Erica Peirson, ND, who specializes in thyroid disorders in children with Down Syndrome. In the lecture, she theorized that more people in Ireland have Hashimoto’s because the lower metabolic rate helped them survive the potato famine of the mid-19th century.
Imagine that — thyroid disorders are advantageous in times of famine! Here’s how I think it works.
During a famine, it becomes crucial for us to conserve our resources. What is the best way to conserve resources? Slow down the metabolism. That way, a person can still survive while eating fewer calories.
How do you slow down metabolism? Slow down thyroid function.
How do we slow down thyroid function? Send some inflammatory cells into the thyroid to attack it, so that it doesn’t produce as much hormone.
In a way, hypothyroidism puts us in a quasi-hibernation mode so that we are more likely to retreat to our “caves,” survive on fewer calories, and conserve energy by sleeping a lot more.
While I haven’t found any studies of thyroid antibodies in bears, thyroid hormone activity has been measured to be significantly lower in bears when they hibernate, as compared to when they are out and about catching fish and doing the other bear things that bears do during warm months. This mechanism helps them survive harsh winters when food and resources are scarce. 
We humans have also made our own adaptations to survive difficult times.
How the Immune System Protects Us
To help our species survive, the immune system has an important job to perform: to sense our environment, and to determine what is safe and what isn’t. The thyroid gland is also a part of this sensing pattern. In fact, a 2013 study found that the thyroid gland can sense danger and initiate the autoimmune response. 
The innate immune response is known to be triggered when the thyroid gland becomes infected by a pathogen, like the Epstein-Barr virus, or when it is damaged by radiation or a toxin. The damage to the thyroid tissue releases molecules that call out to the immune system to help clear the pathogens and damaged cells, and begin cell repair.
These molecules are called danger (or damage)-associated molecular patterns (DAMPs). They can initiate and perpetuate an inflammatory response within a tissue or an organ, as the cells that are sent in may further damage thyroid cells. This theory explains why toxins like fluoride, or even excess iodine, can initially damage the thyroid (especially in the presence of nutrient depletions), and can contribute to an autoimmune response.
Many people know that I am a big evolution buff, and from an evolutionary perspective, it makes perfect sense to me that our immune system and thyroid gland are sending a message to our body in times that are not safe.
The Izabella Wentz Safety Theory
I have developed my own theory, which I call the Safety Theory, about the development of autoimmune thyroid disease. What I explain below is based on my work and observations with thousands of people with Hashimoto’s, a concept known as adaptive physiology, and some of the leading theories of autoimmune disease. These include the bystander effect, molecular mimicry, thyroid-directed autoimmunity, and the three-legged stool of autoimmunity.
Adaptive physiology is a concept that suggests that our bodies develop chronic illness to adjust to our environments, and that chronic illness serves a protective role.
Our bodies have evolved, or were brilliantly designed, to achieve two main goals:
1 – To help us survive
2 – To reproduce and perpetuate our species
In essence, our bodies are constantly adapting to our environment in a way that will ensure the best for us as individuals, as well as for the future of our species.
We know that women carry the primary responsibility of bringing new life into our world. This means that women are particularly tuned into sensing the environment to make sure that the time is prime for reproduction. After all, pregnancy is a huge stress on the body and requires greater resources. In situations where resources are scarce, it’s generally easier to survive if you’re not pregnant. As infertility is often a side effect of thyroid disease, perhaps the immune system attack on the thyroid gland is an effort to help us survive.
Here’s the message our body is hearing from our immune system:
“You’re not safe here. This is not a good time to reproduce. I’m going to help you get through the tough winter by slowing down your metabolism. This will allow you to hold on to more weight to keep you fed when food is scarce. I’m also going to make you cold and tired so you don’t venture out of your cave… because that will keep you safe.”
Back when we were cavewomen, one of our main sources of stress would have been a lack of food. When we ate things that we were not adapted to digest, had deficiencies in nutrients, or didn’t eat at all due to a shortage of food available in our area, our actions sent a message to our bodies that we needed to conserve resources and reduce calorie burning.
Today, we can send the same signals to our bodies by:
- Eating things that are considered food today, but would not have been recognized as food by cavewomen (causing digestive difficulty)
- Eating a processed diet lacking in essential nutrients (leading to nutrient deficiencies)
- Being on a calorie-restricted diet (we may burn fewer calories or store fat if our bodies feel they need to prepare for famine because food is scarce)
For example, humans are not able to eat most grasses in their natural state due to not having the ability to ruminate (chew and digest food more than once). However, modern agriculture has found a way to process grasses (like wheat) to make them “edible” for humans. Of course, I use the word “edible” loosely; even with all of this processing, research is finding that there are still components of these foods that are highly indigestible to humans. Most notably, the protein gluten found in wheat.
Women’s Safety in Modern Society
In addition to food “shortages,” my Safety Theory also accounts for other situations where women are less safe than men, and therefore experience higher rates of thyroid conditions. One reason is that, simply, it is safer to be a man than it is to be a woman.
The most prominent example here is that women are more likely to be physically, emotionally, and sexually abused compared to men, and abuse sends a signal to our bodies that we are not safe. Multiple studies have confirmed that thyroid hormone alterations are present in people who have been abused:
- In 2000, researchers Stein and Barrett-Connor found that past sexual assault was associated with an increased risk of breast cancer, arthritis, and thyroid disease. 
- A 2005 study found that altered thyroid activity was found in women with post-traumatic stress disorder (PTSD) associated with childhood sexual abuse. 
- Two studies found alterations in thyroid hormone levels in women who were sexually abused and had co-occurring menstrual-related mood disorders. 
- Higher rates of Hashimoto’s were found in victims of child abuse, and researchers concluded that: “Severe childhood-trauma-related stress may promote lasting altered thyroid levels.” 
- Battered person syndrome (previously called “battered woman syndrome”) is experienced by people who are victims of physical, emotional, and sexual abuse. Health complaints like asthma (an autoimmune disorder) and fibromyalgia (often connected to Hashimoto’s and other thyroid antibodies) are very commonly reported symptoms of this syndrome.
- Some PTSD studies have found that people who have undergone traumatic stress events may have alterations in their thyroid hormone release patterns. Some may show higher levels of T3/T4, while others may show lower levels of T4. 
- A 1999 study by Wang and Mason reported that former prisoners of war (POWs) with evidence of combat-related PTSD, show increased levels of free and total T3. These levels of thyroid hormone may be reflective of the ex-POWs’ reports of “shutting down” or “stonewalling” (refusing to communicate or cooperate) as well as hyperarousal, behaviors that were more life-preserving compared to a fight-or-flight response that may have put their lives in danger. 
- Another study that measured hormone profiles in military survival training showed reduced levels of T3 and T4, but increased thyrotropin, within 12 hours of captivity. 
It may be easy for people to recognize physical abuse, but emotional abuse may also be a factor in feeling unsafe. Even “social defeat situations,” such as being picked on by “mean girls,” can cause a person to feel unsafe in their environment. In cavewoman times, if you were rejected by society, your chances of survival were reduced.
Can Hashimoto’s Help Us Survive?
While it may be hard to think of Hashimoto’s as a desirable condition, I do believe that it developed as a mechanism to help us survive as a species. Here are some of the ways that it could do this:
- Hashimoto’s makes us want to sleep and withdraw, be less fertile, and carry more weight, which increases our chances of survival.
- Hypothyroidism makes us less fertile, lowers our libido, and possibly makes us less attractive to potential partners and those who threaten us (i.e. our abusers). (This manifests as hair loss, weight gain, dull skin, and pheromone changes.)
- The anxiety experienced due to thyroid cell breakdown, may make a person more hyper-vigilant to potential dangers.
- Mental health professionals who work with people who are overweight, report that those who have been physically abused may inadvertently go on to form a protective barrier around themselves. A person who was abused or felt vulnerable may feel “protected” by the excess weight.
- Being tired, depressed, apathetic, and withdrawn means that we are more likely to stay inside and sleep to conserve energy; and we are less likely to be out in the world where we could be attacked and/or exposed to toxins.
- If our trigger is a stealth infection, thyroid disease makes us withdraw to help us focus on healing the infection. This also prevents the spread of the infection to others.
- During postpartum, when prolactin is elevated (in addition to thyroid antibodies), our likelihood of becoming pregnant again is lowered. This ensures that we are conserving resources for ourselves and our newborns.
If you have thyroid disease, thank your body for having this genius design that has helped you survive.
How to Tell Your Body That You Are Safe
The good news is that there are many things you can do to make your body feel safe again so that you can emerge from your “cave” and feel better.
Wouldn’t it be great if we could just tell our immune systems to stop attacking our thyroid glands and bodies, and that we are actually relatively safe in this unsafe world? However, rather than repeating mantras and telling yourself that you are safe (though I always love those), the key is to communicate to your body in a language that it will understand.
In simple terms, you must eliminate the things that make your immune system believe that you need to conserve your body and resources.
In my work, I’ve found that there is often a combination of triggers that fuels Hashimoto’s, and that a trigger can be anything that has the potential to stress the body or mind, upset the gut barrier, or clog up our detox pathways.
Though triggers will vary from person to person, there are a series of protocols that I have developed to get to the root cause of Hashimoto’s and allow the body to heal:
- Support the liver: In this modern world, we are exposed to an unprecedented number of toxins every day. We inhale them through the air, absorb them through our skin when we use our personal care products, and ingest them through the foods we eat. We also consume fluoride from our water sources. We can begin the healing process by removing hidden toxins from our everyday lives, and helping our livers process out the toxins that are already in our bodies. To accomplish this, we can remove potentially triggering foods, add supportive foods to our diets, reduce our toxic exposure, and support our detox pathways. For more information, take a look at my article on the importance of supporting the liver.
- Restore the adrenals: From surveying my clients with Hashimoto’s, I estimate that around 90 percent of Hashimoto’s patients are also dealing with some degree of adrenal dysfunction, which can manifest as insomnia, fatigue, dizziness, low blood sugar, anxiety, and stress, among other symptoms. We can support our stress hormones by embracing stress-reduction techniques that will help shift our bodies into a regenerative process so we can become stronger and more resilient. To do this, we need to learn how to rest, de-stress, reduce inflammation, balance blood sugar, and replenish nutrients. My most recent book, Adrenal Transformation Protocol, covers healing the adrenals in depth with a four-week program to help you feel more energetic, focused, and less stressed. This is important, as stress does not send a safety signal to your body!
- Balance the gut: In my experience working with people with Hashimoto’s, intestinal permeability has been a factor in every case, and research supports that intestinal permeability is a factor present in autoimmune diseases, including Hashimoto’s.  By optimizing our gut health and restoring microbial balance in our intestines, we can start healing from within! To do this, we can remove reactive foods, supplement with enzymes, balance our gut flora, and nourish our gut. For more information, please see my article on the importance of gut health.
- Dig deeper: Some of us will need to dig a little bit deeper to identify and address our unique triggers. This may include optimizing thyroid hormones, addressing hidden infections, and removing other sources of toxic exposure, such as dental amalgams.
Be sure to check out my book Hashimoto’s Protocol to learn more about all the protocols I recommend to help you support safety and healing, uncover all the root causes of your symptoms, and start feeling better.
By the way, because nutrition is such a key factor in helping our bodies to heal and letting them know that we are safe in this world we are living in, I wrote a cookbook a few years ago, full of information to help you uncover your own nutrient deficiencies, improve your digestion, and find the right diet that will allow you to thrive. The goal is to teach your body that you are “safe” by providing it with all of the nutrition it needs.
In addition to all of the nutritional guides, my cookbook, Hashimoto’s Food Pharmacology: Nutrition Protocols and Healing Recipes to Take Charge of Your Thyroid Health, contains 125 easy and delicious recipes to support your thyroid health. Be sure to check it out as well!
In the meantime, here are some things you can do to make your body feel safe today:
Treat your body like your cherished temple. Be nice to it. Feed it nutritious foods when it’s hungry. Don’t skip meals. Don’t subject it to unnecessary stresses like working all day instead of playing or resting.
Sleep when you’re tired. Don’t cover your body up with harsh makeup and skin creams.
Don’t silence its subtle signals. Stop forcing it to have more caffeine when you’re tired.
Let it rest. Don’t drench it in antacids when it’s trying to tell you a food you’re eating is not working. Listen to it and care for it as you would care for a dear friend, pet, or child.
I want you and the women you love, to live your best lives, and I know it’s possible. If you found this information helpful, please consider paying it forward by sending it to another woman with a thyroid condition.
Do you think the Safety Theory applies to your condition?
P.S. You can download a free Thyroid Diet Guide, 10 thyroid-friendly recipes, and the Nutrient Depletions and Digestion chapter of my first book for free by signing up for my newsletter. You will also receive occasional updates about new research, resources, giveaways, and helpful information.
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Note: Originally published in January 2017, this article has been revised and updated for accuracy and thoroughness.