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Thyroid Dysfunction and Gastrointestinal Health

Doctor holding model thyroid up to throat

As a naturopath, more often than not, I encounter patients dealing with a complex web of interconnected health concerns. One such area that has garnered increasing attention in recent years is the relationship between thyroid function, gastrointestinal (GI) health, and nutrient imbalances.

Emerging research has revealed some interesting findings. It has been discovered that being hypothyroid is the factor most strongly associated with small intestinal bacterial overgrowth (SIBO), even more so than factors like intestinal surgery or acid-suppressing medication (such as proton pump inhibitor) use. Additionally, patients with SIBO are more likely to also have thyroid autoimmunity.

Intrigued by these connections, recent research has explored the potential benefits of probiotic supplementation for hypothyroid patients. The results have demonstrated that the patients experienced
1) a reduction in thyroid-stimulating hormone (TSH) levels.
2) required lower doses of thyroid replacement medication (like thyroxine)
3) reported improved fatigue scores

All after just a short course of probiotic intervention. The researchers attribute these improvements to
1) probiotics’ anti-inflammatory effects
2) their ability to address SIBO
3) their potential to enhance the absorption of thyroid medication.

The relationship between GI imbalances and autoimmunity extends beyond just thyroid conditions. Increased intestinal permeability, often referred to as “leaky gut,” has been associated with a variety of autoimmune disorders. Interestingly, this gut barrier dysfunction is also found at higher rates in individuals with thyroid dysfunction and is linked to more pronounced thyroid-related symptoms.

Adding to the complexity, a significant portion of patients with autoimmune thyroid disease also have antibodies targeting the gastric mucosa, parietal cells in particular. This condition, known as autoimmune gastritis, can lead to reduced stomach acid production (hypochlorhydria) and subsequent difficulties digesting food and absorption generating deficiencies in nutrients like iron and vitamin B12. In fact, up to 4 in 10 hypothyroid patients may be deficient in vitamin B12, potentially contributing to symptoms such as fatigue!

This information highlights the interconnections between thyroid function, GI health, and nutrient imbalances. By recognising and addressing these relationships, naturopathic practitioners really shine, as we utilsie our holistic approach to managing complex cases and optimising patient outcomes.

As we continue to unravel the intricacies of these interconnected systems, it becomes increasingly clear that a comprehensive, integrated perspective is essential for providing the best possible care for our patients.

If you are dealing with thyroid-related concerns, I would be happy to work with you to investigate potential underlying factors and develop a personalised plan to support your overall health and wellbeing as a naturopathic practitioner.

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