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How Chronic Stress Can Impact Your Adrenals and Thyroid

Written by Dr. Michael Ruscio, DC on March 12, 2022

Written by Dr. Michael Ruscio, DC on March 12, 2022 — Reviewed by Dr. Hannah Hamlin

Chronic Stress Management Is Essential for Balanced Hormones

• The Adrenal-Thyroid Connection|
• How Cortisol Affects Adrenals and Thyroid Health|
• Managing Cortisol for Adrenals and Thyroid Function|
• Adrenal-Supporting Herbs for Thyroid Health|
• Curb Chronic Stress|

There is a connection between the adrenal glands and the thyroid gland, but current research tells us that this connection is less of a direct, causal relationship of one affecting the other and more of a shared relationship to chronic stress. 

The adrenals and thyroid both produce key hormones needed for our response to stress, maintaining our metabolism, supporting our digestion, and many other functions. When we take on constant chronic stress from internal or external sources, these stressors rob the raw materials — like minerals and other micronutrients — needed to produce other hormones in favor of producing stress hormones instead. 

Managing the stress response becomes a key point in maintaining both adrenal and thyroid health, as well as the health of the endocrine system broadly [1, 2]. In this article, we’ll discuss adrenal and thyroid health and how chronic stress connects the two. We’ll also provide some concrete action steps to improve your adrenal and thyroid function that we’ve seen work time and again at the Ruscio Institute for Functional Medicine.

The Adrenal-Thyroid Connection

The adrenal glands and thyroid gland are definitely connected — to a point. They’re both glands that produce hormones and are part of the endocrine system. They also share a connection to the hypothalamus and pituitary gland, parts of the brain that release their own hormones, corticotropin-releasing hormone (CRH) and adrenocorticotropic hormone (ACTH). These hormones signal the adrenals to release cortisol (the stress hormone) and the thyroid to release thyroid hormone. We call these hormone chain reactions the hypothalamus-pituitary-adrenal (HPA) axis and the hypothalamus-pituitary-thyroid (HPT) axis.

While the adrenals don’t have a direct influence on the thyroid or vice versa, what the research suggests is that a dysfunctional HPA axis (where the adrenals overproduce or underproduce cortisol) may result in a suppressed HPT axis, eventually leading to systemically low levels of cortisol and thyroid hormones [1].

Overall, the relationship between the adrenal and thyroid glands is complex and still being understood. Since the HPA axis is activated by stress (which can include both physical and mental stress), it may be more accurate to say that stress influences thyroid health, and this process is partly mediated by the adrenal glands. 

Chronic Stress, HPA Axis Dysfunction, and the Thyroid

We’ve discussed in other articles that “adrenal fatigue” or adrenal dysfunction isn’t a recognized medical diagnosis at this time, although the symptoms are very real. 

Usually what people mean when they say they have adrenal fatigue is that they’ve internalized chronic stress that is causing physical symptoms, whether that stress stems from gut health imbalances, autoimmune disease, prolonged emotional distress, self-imposed or outside pressure to perform at work or school, or a number of other factors. 

Chronic stress can easily cause a number of problems in the body, including hormonal imbalances — such as a lack or excess of thyroid and adrenal hormones. 

A 2021 literature review found that an imbalance of the HPA axis from chronic stress may affect all hormonal systems, including the HPT axis. The review stated that continuous activation of the HPA axis can result in decreased thyroid-stimulating hormone (TSH) production and impaired conversion of T4 to T3, possibly due to increased levels of glucocorticoids (cortisol) [1].

So instead of saying that we need to focus on adrenal health to support the thyroid, what we really need is to reduce our chronic stress load, which significantly affects the actions of both the adrenals and the thyroid gland. 

How Cortisol Affects Adrenals and Thyroid Health

Cortisol is the “stress hormone,” released by the adrenal glands in high amounts when there’s a dangerous situation at hand. If that danger is a predator for example, cortisol helps us either fight or run away. 

But cortisol is not only released when we’re dealing with a dangerous situation; we have some level of cortisol in our bodies at all times throughout the day. It should be at its highest levels in the morning when we wake up, and at its lowest levels at night while we’re sleeping. 

Functions of cortisol include:

• Immune system suppression (This is why doctors prescribe corticosteroids, essentially synthetic cortisol, for many types of autoimmune diseases) 
• Maintenance of blood pressure
• Increasing blood glucose to give us energy
• Increasing fat breakdown and fat storage

When cortisol output fluctuates wildly or is consistently high, problems begin to arise. Chronic stress results in repeated elevations of cortisol, and can manifest the following symptoms [3]:

• Bone and muscle breakdown
• Fatigue 
• Depression 
• Pain 
• Memory impairments
• Electrolyte imbalances 
• Orthostatic hypotension (dizziness when going from seated to standing)
• Impaired pupillary light reflex
• Inflammation 

Very low levels of cortisol can occur with a rare adrenal disease known as Addison’s disease [4]. Symptoms include:

• Fatigue
• Weight loss
• Low blood pressure 
• Dark spots on the skin (known as hyperpigmentation)
• High blood potassium levels and low sodium. 

Improving adrenal and thyroid health by correcting cortisol levels very much depends on two things: 

1. The underlying root cause of the imbalance 
2. Whether cortisol is high or low 

For example, Addison’s disease is an adrenal autoimmune condition that results in very low cortisol levels, known as adrenal insufficiency. Addison’s has been associated with elevated levels of TSH [5, 6], and correction of Addison’s (raising cortisol levels) helps to normalize TSH levels [5].

On the reverse side, an observational study examined the effects of Cushing syndrome (an adrenal condition that causes high cortisol output) on thyroid function. Of the study participants, the results showed that half of Cushing patients had low thyroid hormone that normalized six to 12 months after treatment [7].

These findings indicate that chronically elevated levels of cortisol seen in Cushing syndrome inhibit thyroid function. 

However, high cortisol levels don’t always mean low thyroid hormone levels and vice versa. A 2021 observational study looked for correlations between cortisol and thyroid hormone levels. A total of 152 adults who were either healthy or had a diagnosis of subclinical hypothyroidism had their TSH and cortisol levels measured, and the results showed there was a positive correlation between cortisol and TSH levels — meaning elevated cortisol levels were correlated with elevated TSH levels [8].

Context is key when we’re discussing cortisol levels, adrenals, and thyroid health. Someone who has Cushing syndrome will have a very different imbalance of hormones than someone with hypothyroidism or Hashimoto’s disease. In some ways, this means their treatment will differ, but there are also some things we can implement across the board for better cortisol management and therefore, better adrenal and thyroid function.

Managing Cortisol for Adrenals and Thyroid Function

Improving adrenal and thyroid health isn’t necessarily about therapies that target those glands directly. Let’s take a look at some of the other factors that influence cortisol levels, adrenals, and thyroid health. 

The Gut Health Piece

Gut health is an often-overlooked underlying cause of thyroid dysfunction and high or low cortisol. For example, a pathogen that’s taken up residence in the gut is a significant stressor to the body, and that stressor can easily cause spikes in cortisol levels. Not digesting food and absorbing nutrients well through an impaired gut lining is another stressor that may contribute to increased cortisol levels. 

Action step: In addition to the foundations of a healthy diet and lifestyle, adding one probiotic from each of the three main categories (multispecies, S. boulardii, and soil-based), also known as probiotic triple therapy, to your daily routine can greatly improve gut symptoms like gas and bloating. Probiotics may also improve typical “hypothyroid” symptoms like anxiety and low energy levels [9]. 

One case study from our clinic that supports addressing gut health for subclinical hypothyroid symptoms is Beth’s story. Beth came to us with anxiety, some gas, bloating, and fatigue, and upon further investigation, some intolerance to leftover foods, vaginal dryness, disinterest in sex, and brain fog. And going even further, she also presented with hypotension, low blood pressure, and episodes of dizziness when standing.

At first glance, her initial symptoms say “thyroid problems.” But upon further investigation, we found that it was actually gut imbalances and a lack of nutrients from her diet that were the main drivers of her symptoms.

And by the way, the lack of nutrients wasn’t because she was eating an unhealthy diet — she had actually tried versions of the low FODMAP and low histamine diets and was sticking to them consistently. She simply wasn’t eating enough food, especially carbs.

The Nutrition Piece (Are You Eating Enough Food?) 

Another factor that may place a burden on the HPA axis includes consuming too few calories. 

One RCT found that caloric restriction significantly increased cortisol levels in women [10], therefore suggesting adequate caloric intake may be helpful for people with thyroid symptoms (as was the case with Beth).

When you’re under-eating, this typically means you aren’t getting enough of your essential nutrients either, like electrolytes and vitamins. Adding in additional electrolytes along with increasing her carb intake represented a significant improvement in symptoms for Beth.

Action step: If you’ve been on a low-carb diet for some time and you’re experiencing adrenal and thyroid symptoms, try increasing your healthy carbs and see whether your symptoms improve.

The Chronic Stress Piece

When discussing cortisol, adrenals, and thyroid health, we have to bring up chronic stress. Some chronic stress is internal, like your gut health, as we just addressed. 

But most of us see stress as external, like: 

• Working every day in a job you hate
• Difficult interpersonal relationships
• Being financially and emotionally responsible for children, aging parents, and/or other family and friends
• Carrying unresolved trauma that becomes internalized in the body (the issues in the tissues)
• Choosing to view the world as a dangerous and hateful place that’s only getting worse 

Most of us are currently experiencing at least one chronic stressor, whether it’s one of the above or something else. When you stack them up two or three at a time, it’s no wonder our cortisol levels become dysregulated and physical symptoms begin to manifest in the body. 

There’s no getting around it: Chronic stress must be improved to see improvements in physical symptoms. Again, sometimes this means getting more nutrients that help you handle stress better. But sometimes it means adjusting your perspective on your job or putting boundaries in place with people who bring you down mentally and emotionally.

One of our patients, Danielle, used limbic retraining techniques to improve her response to stress and calm her nervous system enough that her body felt safe to heal. For her, this intervention was essential before she could do any other therapies to heal her physical symptoms. You can listen to her story here. 

Action step: How can you improve your response to stress? Implement one stress-relieving technique into your daily routine, like meditation, walking, exercise, journaling, or anything else you find calms your mind and body. That might mean taking a nap!

Adrenal-Supporting Herbs for Thyroid Health

For additional adrenal support, adaptogenic herbs may assist with both adrenal function and thyroid health, either directly or indirectly by improving the stress response. 

Only the adaptogenic herb ashwagandha has clinical trials demonstrating its benefits for thyroid health. Ashwagandha was shown to improve TSH and thyroid hormone levels in patients with subclinical hypothyroidism in one RCT [11].

However, other herbs appear to improve stress, which may be helpful for thyroid function in an indirect way.

A supplement containing eleuthero root extract was shown to improve burnout symptoms [12].

Rhodiola has been shown to improve stress symptoms, fatigue, and exhaustion in one study [13]. Another study found that rhodiola improved stress symptoms, disability, functional impairment, and overall well-being [14]. Additionally, a literature review found that rhodiola may reduce stress hormones and prevent chronic stress [15].

These adaptogenic herbs may be helpful for both adrenal and thyroid support, especially in times of significant chronic stress.

Curb Chronic Stress for Better Adrenals and Thyroid Health 

When looking at adrenal and thyroid issues, blood tests such as thyroid levels only show a small percentage of the full picture. It’s equally if not more important to look at what’s causing chronic, systemic stress in your life and addressing those root causes. When you make those changes, that’s when you begin to see sustainable healing. 

To find an integrative health practitioner who will work with you to establish a reasonable and cost-effective treatment plan for thyroid disease — such as hypothyroidism or hyperthyroidism, subclinical hypothyroidism, or HPA axis imbalances — reach out to us at the Ruscio Institute for Functional Health.

The Ruscio Institute has developed a range of high-quality formulations to help our patients and audience. If you’re interested in learning more about these products, please click here. Note that there are many other options available, and we encourage you to research which products may be right for you.