Understanding the the Gut-Thyroid Connection for Optimal Health

Understanding the the Gut-Thyroid Connection for Optimal Health

Published on Monday, April 08, 2024 by Keydella Fuller

Exploring the Surprising Connection Between Thyroid Imbalances and Digestive Disruptions 

The thyroid, a small gland in the neck, plays a significant role in regulating metabolism, energy production, and overall hormonal balance. Gut health influences our digestion, brain, and immune health and plays an important role in regulating thyroid hormones. Imbalances in gut health can lead to thyroid dysregulation, manifesting in various symptoms and even autoimmune thyroid conditions. This article explores the symptoms of thyroid conditions, the link between gut health and thyroid function, and natural strategies to alleviate some symptoms through gut rebalancing.

Symptoms of Thyroid Conditions

Thyroid disorders are categorized into hypothyroidism (underactive thyroid) and hyperthyroidism (overactive thyroid), each presenting with distinct symptoms.

Hypothyroidism symptoms include fatigue, weight gain, cold intolerance, constipation, dry skin, hair loss, and depression.

Hyperthyroidism is characterized by weight loss, anxiety, irritability, heat intolerance, frequent bowel movements, and sleep disturbances.

You can have what is termed subclinical hyper- or hypothyroidism; this means 1 marker may be out of range or just barely in range, but you still have manifestation of the disease based on symptoms. It is important that when your practitioner checks your thyroid function, more than just a thyroid stimulating hormone (TSH) is checked, as this is not the only test involved in a full thyroid panel. Find a functional or holistic professional if needed, as many conventional providers may not acknowledge treatment is needed if labs are “in range,” but symptoms are present. These symptoms are not only unpleasant but can significantly impair one's quality of life.

The Gut-Thyroid Axis

You may have heard about the gut-brain connection, but there is a very significant and critical gut-thyroid connection—who knew? This gut-thyroid connection, like the brain, refers to the bidirectional relationship between the gastrointestinal system and the thyroid gland. Yup, the gut talks to the thyroid and the gut bacteria influence the way the thyroid functions. 

The gut plays a pivotal role in nutrient absorption needed for thyroid conversion, including iodine, selenium, and iron absorption. These help the thyroid take the inactive form thyroxine (T4) and turn it into the active form triiodothyronine (T3). Certain microbial strains, like Firmicutes and Bacteroidetes, have been shown to balance out thyroid function, while strains like streptococcus have been shown to be potentially harmful and promote thyroid dysregulation. Additionally, if you are on thyroid replacement medication, the Lactobacillus reuteri strain may help make your medication more effective, leading to fewer dose adjustments. 

So, it's easy to see how an imbalance in the gut microbiota, aka dysbiosis, can impair thyroid hormone conversion, increase the risk of autoimmune thyroid conditions, and exacerbate the symptoms of existing thyroid disorders.

Natural Ways to Reduce Symptoms Through Gut Health

  1. Probiotics and Prebiotics: Incorporating foods rich in probiotics (such as yogurt, kefir, and fermented vegetables) and prebiotics (found in garlic, onions, bananas, and asparagus) can help balance the gut microbiota, improving thyroid function and reducing symptoms.
  1. Anti-inflammatory Diet: Adopting an anti-inflammatory diet, emphasizing fruits, vegetables, lean proteins, and healthy fats, can reduce gut inflammation and thereby support thyroid health.
  1. Gluten-Free Diet: For some individuals, especially those with autoimmune thyroid conditions, eliminating gluten has been shown to lower thyroid antibodies and may be an option for some individuals.
  1. Bone Broth: Rich in nutrients and amino acids, bone broth can help heal the gut lining, reducing the permeability and the associated risk of autoimmune reactions affecting the thyroid.
  1. Stress Management: Chronic stress can impair both gut health and thyroid function. Practices such as yoga, meditation, and mindfulness can help manage stress by activating the parasympathetic, rest and digest, nervous system.
  1. Adequate Sleep: Ensuring sufficient sleep is vital for gut health and hormonal balance, including thyroid hormones. Aim for 7-9 hours of quality sleep per night.
  1. Regular Exercise: Moderate exercise can improve gut motility and reduce inflammation, supporting overall health and thyroid function. Too much high-intensity exercise can actually be too stressful on the body. 

In Summary: Prioritizing Gut Health for Optimal Thyroid Function

The link between gut health and thyroid function is fascinating. To care for your thyroid, first care for your gut. The seven gut health tips provided above will get you on your way to restoration. This is one aspect of thyroid health. Interventions that focus on lifestyle (as discussed above) and environmental factors can play a role in your thyroid health. 


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