Hypothyroidism and IBS

Your gut and thyroid impact each other in different ways. When one system is disrupted, the other is also affected and disease can occur. In this article, we’ll review the relationship between hypothyroidism and IBS, and explain some treatment options we recommend for individuals with both of these conditions.

Commonly referred to as an “underactive thyroid”, hypothyroidism occurs when your thyroid gland does not make enough thyroid hormones to meet the body’s demand. Thyroid hormones control many bodily functions like metabolism, body temperature, your menstrual cycle, heart rate, and more. 

An autoimmune condition called Hashimoto’s is the most common cause of hypothyroidism in the United States. Common symptoms of hypothyroidism include brittle nails, thinning hair, fatigue, weight gain, constipation, and cold intolerance. 

Irritable bowel syndrome (IBS) is a gastrointestinal disorder in which people suffer from a variety of digestive symptoms like gas, bloating, abdominal pain, constipation and/or diarrhea. Some studies suggest that IBS is caused by dysbiosis—an imbalance of gut bacteria. Small intestinal bacterial overgrowth (SIBO) is one type of dysbiosis that may be responsible for many IBS symptoms. Read more about SIBO and hypothyroidism.

If you have IBS, you may be more likely to also have hypothyroidism. One small study found that 19 percent of people with IBS also had a thyroid disorder (1). Interestingly, the majority of these people suffered from subclinical hypothyroidism. This occurs when your thyroid labs (like TSH) appear to be “normal” for conventional medicine standards, yet you continue to suffer from symptoms of hypothyroidism. In functional medicine, we use a narrower, more optimal, range of TSH to capture individuals with subclinical hypothyroidism. 

Hypothyroidism and IBS may commonly occur together because they both share a possible root cause: dysbiosis. As mentioned earlier, dysbiosis is a general term that refers to an imbalance of gut bacteria. People with dysbiosis may have too many bad bacteria, not enough good bacteria, or a mixture of the two. Studies have found over half of patients with hypothyroidism also have dysbiosis (2). 

Secondly, Gut Health Rebalance is a powder containing the perfect synergy of ingredients to heal the gut lining, like slippery elm and aloe vera extract. We often recommend this powder after or in conjunction with Microbiome Balance for a gut healing protocol. 

Unsurprisingly, chronic stress negatively affects both IBS and hypothyroidism. First of all, unmanaged stress causes the body to redirect thyroid hormone (T4) into an alternative and unusable form called reverse T3. Your body requires a delicate balance of reverse T3. Too much of this hormone as a result of chronic stress can slow metabolism and make hypothyroidism worse. Furthermore, stress negatively impacts individuals with IBS by affecting digestion, GI motility, and worsening IBS symptoms (3). 

Take some time to reflect on the stressful aspects of your life. Is it possible to reduce or eliminate these triggers? Sometimes, stress is unavoidable. Therefore, we must introduce healthy ways to manage stress by implementing mind-body practices like yoga, meditation, journaling, walking, or deep breathing exercises. 

Hypothyroidism occurs when your thyroid gland does not produce enough thyroid hormones to meet the body’s demand. IBS is a GI disorder in which individuals suffer from a variety of digestive symptoms. Hypothyroidism and IBS may occur together because they both have dysbiosis as a potential root cause. You can support optimal gut and thyroid health by eliminating gut disruptors (like added sugar and FODMAPs), slowly increasing your fiber and fluid intake, improving gastric motility with effective supplementation, and lowering stress levels. 

Want to learn more? We teach you how to heal the gut and treat the root causes of hypothyroidism in our functional medicine membership program.