Hypothyroidism: Bloating and the Immune System

Do you struggle with bloating, cramping, gas, and indigestion? You’re not alone.

Written by Raphael Kellman, MD

Thyroid dysfunction is commonly misdiagnosed since symptoms can be non-specific and vague, which are easily mistaken for other health conditions. The common tests used to assess thyroid function are limited and often insufficient for proper diagnosis. Many people suffer from hypothyroidism, estimates vary on how many, but it’s thought that 4.6% of the U.S. population over the age of 12 suffers from hypothyroidism. As people age, they have a higher risk of getting hypothyroidism. Patients are commonly diagnosed incorrectly which leads to complications and the wrong treatments for their diagnosis. According to the American Thyroid Association, up to 60% of those with thyroid dysfunction are unaware of their condition.  

Hypothyroidism is associated with a wide range of gastrointestinal (GI) symptoms, including gas, bloating, constipation, and others. Many people end up seeking treatment for their GI issues, without realizing that they may have an issue with their thyroid. 

How is gut health related to thyroid dysfunction?

Your gut contains trillions of bacteria, which are crucial to your health and play a specific role in thyroid function. The gut microbiome plays an important role in our ability to appropriately digest and assimilate nutrients. The thyroid produces two different forms of thyroid hormone: T4 (inactive form) and T3 (active form). Two key nutrients are required to both make thyroid hormone and to convert from the inactive form to the active form. Iodine is a key component of thyroid hormone. Since the gut bacteria aid in breaking down food, this is also how the body sources iodine to produce thyroid hormone. Selenium is also a crucial nutrient when it comes to thyroid function. It is sourced from the food we eat with the help of the bacteria in the gut and it is required for the conversion of T4 to T3.  

Without selenium, this conversion of T4 to T3 cannot happen, which leads to a state of hypothyroidism. Further, an imbalance in the gut microbiome not only leads to a lack of diversity of specific beneficial bacteria, which are crucial to our health, but also leads to an increase in pathogenic bacteria.   

Pathogenic bacteria can feed off the nutrients we need to produce thyroid hormone, which can directly reduce the amount of thyroid hormone we are producing. Over time these pathogenic bacteria can lead to damage to the GI lining and eventually “leaky gut syndrome”. This is when the chronic inflammation in the gut causes damage to the GI lining, which leads to small openings in the lining. This allows small pieces of undigested food to leak into the bloodstream causing an associated immune reaction.   

Common symptoms of leaky gut include cramping, bloating, gas, and indigestion. It’s very common for people who are finally diagnosed with some form of hypothyroidism to complain of GI dysfunction and distress. By addressing and reversing these imbalances in the gut microbiome, as well as healing the gut lining, many patients are able to appropriately address and resolve the root cause of their thyroid dysfunction.

How is the immune system related to thyroid and gut health?

The health of our microbiome directly impacts our immune system. It is estimated that somewhere between 70-80% of our immune system is in our gut. It has been said by several researchers that nearly 90% of all diseases can be tracked back to the health of the gut and the microbiome. Therefore, any imbalances in the gut microbiome directly result in a sub-optimal functioning of our immune system, leaving us vulnerable to a variety of diseases and chronic conditions. 

In particular, leaky gut and being in a state of chronic systemic inflammation can result in an autoimmune condition, such as Hashimoto’s Disease, which is a common type of hypothyroidism, as well as rheumatoid arthritis, inflammatory bowel disease (IBD), psoriatic arthritis and others. Hashimoto’s disease is the most common form of hypothyroidism, and it’s estimated that 80-90% of people with hypothyroidism have this type.  

There is a direct correlation between gut dysfunction, often manifested as GI systems, and thyroid dysfunction and an impaired immune system.

Why is hypothyroidism often misdiagnosed?

There are a variety of reasons why so many people suffer for years with low thyroid function, all while being told by their doctors that their thyroid is “fine”. Part of it is that people who suffer from hypothyroidism often report non-specific, often vague symptoms that don’t definitively point to a particular diagnosis. The routine thyroid tests commonly used by most doctors often miss low thyroid function. Many patients report going to several doctors and being told that the conventional thyroid panel shows that their thyroid hormones are within “normal range” and that their thyroid is functioning properly.   

There are several main problems with this testing approach as thyroid hormone levels fluctuate so a transient low level may be missed. An elevated Thyroid Stimulating Hormone (TSH) is a common indicator of hypothyroidism, however there are several conditions which can cause TSH to remain low masking the underlying thyroid dysfunction. The “normal range” in most blood tests is somewhat arbitrary. In reality, everyone’s “normal range” may be slightly different, and you need to look at blood results and take symptoms into consideration.   

Many patients suffer from all the classic symptoms of thyroid dysfunction and their thyroid hormone levels are still “normal”. Often symptoms appear well before the thyroid dysfunction is apparent on the routine thyroid panels.  

Unlike more conventional thyroid tests, the TRH Stimulation Test can detect low thyroid often missed by normal lab tests. As such, the TRH Stimulation Test is by far the best way to not only diagnose thyroid conditions, but also monitor treatment and ensure the most effective, as well as the correct type of medication is being used. Most doctors, conventional or holistic, do not use this test though it can be a game-changer for patients.  

Historically, the TRH Stimulation Test was routinely used by physicians except it has now been replaced by cheaper and easier testing methods. Subsequently, many patients report suffering many of the classic symptoms associated with thyroid dysfunction, yet they are told by their doctors that the current thyroid test shows normal levels of thyroid hormones.

The TRH Stimulation Test

When circulating levels of thyroid hormone in the blood are low, the pituitary gland releases TSH, which in turn stimulates the thyroid to release thyroid hormone, thereby regulating our metabolism. High levels of TSH in the blood are often indicative of a low functioning thyroid.   

A baseline blood test is conducted, which checks various thyroid markers such as TSH, T3 and T4, as well as thyroid antibody markers. Next, Thyroid Releasing Hormone (TRH) is injected into the patient. TRH stimulates the pituitary gland to release TSH. Even if the TSH level in the blood is normal, the pituitary will store up a large amount of TSH in people who have a low functioning thyroid. Upon stimulation, the pituitary will release its contents into the bloodstream creating a spike in the TSH level that is easily detected. A second blood sample is drawn and the two TSH levels are then compared. This results in a much more accurate method of testing allowing patients, who might have otherwise had their low thyroid function missed, to be properly diagnosed.

About Raphael Kellman, MD

Dr. Raphael Kellman is an internist and functional medicine physician and founder of the Kellman Wellness Center in New York City. He is a graduate of Albert Einstein College of Medicine and pioneered a groundbreaking new brand of medicine and healing called Microbiome Medicine.

READ NEXT: MICROBIOME HEALTH: THE FOUNDATION OF THYROID HEALTH