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Hypothyroidism, Irritable Bowel Syndrome and Your Health

Thyroid and Digestion Health

Although the thyroid is not directly with associated Irritable Bowel Syndrome, conditions that impact the thyroid can impact gastrointestinal function. Those familiar with thyroid health know that this small gland plays a critical role in almost every system of the body. This is because the thyroid is responsible for releasing hormones that regulate metabolism of all cells in the body. Even small fluctuations in thyroid hormone balance can cause various regions of the body to be negatively impacted.

When the thyroid is overactive (hyperthyroidism) or underactive (hypothyroidism) it can have a dramatic effect on cell metabolism. Depending on the condition, gastrointestinal function can be sped up or slowed to a crawl. Being aware of the impact an underactive thyroid has on digestion and the appropriate steps to take in treating can help resolve gastrointestinal issues brought on by thyroid malfunction.


Because the thyroid is tightly integrated with almost the entire body, it is important that it functions properly. Unfortunately, according to the American Thyroid Association , it is estimated that nearly 20 million Americans suffer from some type of thyroid disease. With so many people experiencing thyroid dysfunction it can be beneficial to have a basic understanding of one of its more prevalent conditions: hypothyroidism.

When the thyroid is incapable of producing the hormones necessary for proper metabolic function, the body experiences a slowing down of nearly all systems. There are a variety of reasons why one’s thyroid may not be able to maintain production. Improper synthesis of T4, the storage form of thyroid hormone, inhibited conversion of T4 into T3, the active form of thyroid hormone, or over conversion of T4 into Reverse T3, a failsafe that inhibits T3 are some of the more common reasons for a thyroid hormone deficit. There are numerous symptoms that may be caused by hypothyroidism that are often misconstrued as a different condition.

Symptoms associated with hypothyroidism include:

Many with hypothyroidism report sensations of sluggishness, brain fog, and a general feeling of low energy. As thyroid function deteriorates and slows, so does the rest of the body. The gastrointestinal system is no different. Hypothyroidism can impact gastrointestinal function and cause symptoms that may lead one to believe they are suffering from IBS.

Contributing Factors

As mentioned above, hypothyroidism does not have a direct correlation to IBS but it does cause various gastrointestinal problems. It is common for those with reduced thyroid function to experience constipation, bloating, and cramping. Furthermore, reduced thyroid function may inhibit cell motility, movement through the digestive tract, that can disrupt nutrient acquisition. In extreme cases, where hypothyroidism has caused the body to slow to a significant degree, esophageal movement can be reduced. This can cause one to experience the following symptoms:

  • Dysphagia (difficulty swallowing)
  • Dyspepsia (abdominal or chest discomfort)
  • Gastroparesis (inability to empty the stomach of food)

Although it is usually an indicator of hyperthyroidism, diarrhea may also be caused by hypothyroidism. It is theorized that the small intestine may become overabundant with bacteria that can inhibit digestion and nutrient absorption. This condition also known as Small Intestine Bacteria Overgrowth or SIBO can more frequently be found in those with hypothyroidism. If left untreated, SIBO can lead to leaky gut syndrome, which can cause serious issues throughout the entire body. Because the systems of the body are so tightly integrated it is important to get adequate testing and understand how elements influence one another.

Covering Your Bases

One may experience IBS and hypothyroidism at the same time. If this is the case, it is important to thoroughly analyze one’s thyroid health to ensure that IBS symptoms are not caused by a thyroid condition. Symptoms caused by a thyroid dysfunction are not resolved in the same manner as those caused by IBS. Furthermore, the presence of celiac disease can cause IBS-like symptoms and agitate the intestinal tract. Those with Hashimoto’s are at increased risk of developing celiac disease. Therefore, it is particularly important to have a thorough examination that covers thyroid, celiac, and IBS before choosing treatment.

Combatting IBS and Hypothyroidism

Making sure one is getting proper treatment begins with identifying the problem. Depending on if one’s digestive issues are being caused by IBS or a thyroid disorder dictates the course of action that needs to be taken. If both are present, it is critical that the thyroid condition is properly treated before focusing on other contributing factors. Thyroid disease can cause a rippling effect of damage that may be reversed entirely if it is resolved appropriately. Taking care of one’s thyroid includes regularly monitoring thyroid and hormone levels, and keeping them balanced by using the treatment that best suits their situation. If left untreated, a thyroid condition can worsen IBS symptoms and make treatment increasingly difficult.

Fiber is an important piece of proper digestive function. If one has a severe fiber deficit in their diet they will likely experience equally severe gastrointestinal dysfunction. Resolving such a situation requires that fiber be added incrementally to one’s diet. If done too quickly, there is risk that IBS symptoms will increase and make it more difficult for the body to absorb nutrients and medications. If one is simultaneously being treated for a thyroid condition, it is important that they take their medication on an empty stomach. Meals that are high in fiber are more likely to disrupt the efficacy of thyroid medication.

Always Getting Involved

As with most conditions involving the thyroid, it is important to be aware of the widespread influence this small gland has over the body. Even though IBS and hypothyroidism are not directly associated with one another, the thyroid finds a way to be involved in gastrointestinal function. If suffering from digestive difficulties, be sure to get tested for a thyroid condition and celiac disease in addition to IBS. Without knowing the problem there is little chance of finding the solution.