A thyroid nodule is an abnormal growth of thyroid cells that create a small lump in the thyroid gland. Oftentimes they go unnoticed, especially if they are small. Nodules are very common, in fact about half of the adults over 60 have them. Most are non-cancerous, but less than 10% contain cancerous cells and need to be removed. Rarely, nodules can increase production of thyroid hormone, in which case they have the potential to contribute to hyperthyroidism.
Nodules are often associated with Hashimoto’s thyroiditis (the most common cause of hypothyroidism). Nodules are believed to be caused by iodine deficiency, which is a prevalent, yet under-recognized problem in the Western world.
It’s unclear what all the causes of thyroid nodules may be. A recent study from Italy addressed this question, and investigated the relationship between diabetes, being overweight, and the incidence of thyroid nodules. Italy is generally known for being iodine deficient, so it can be assumed that a large number of participants in this study did not have adequate iodine levels, automatically putting them at risk for thyroid disorders.
Italy also has a high prevalence of overweight and obesity. Because a person with a large body size has higher iodine requirements, they are at increased risk of iodine deficiency and associated symptoms.
What this study demonstrated is that people who were overweight or obese had a higher likelihood of having thyroid nodules than normal weight people. Obesity was also associated with having larger- sized nodules, and also a higher number of nodules. Being diabetic also increased the risk of having thyroid nodules.
One interesting factor revealed in this study is that people who did not consume milk had a higher risk of thyroid nodules. Milk is considered an important source of iodine, particularly in Italy where iodized salt is is not ubiquitous, even though it’s available. Particular regions of the country, such as Sicily, have high rates of lactose intolerance and therefore people avoid consuming milk. This combination of factors highlights the need for a more impactful method of iodine supplementation in Italy.
Overall, this study found a significant association between obesity, diabetes, and higher rates of thyroid nodules. I believe that Wilson’s Temperature Syndrome may be an early marker on the path that progresses from healthy thyroid function to low body temperatures, declining gut health, increased inflammation and perhaps autoimmunity like Hashimoto’s disease, increased nodules, hyperplasia, and cancer. If this is true, then catching Wilson’s Temperature Syndrome when it develops may be an opportunity to halt the progression to a more serious thyroid disorder.
Learn more about Wilson’s Temperature Syndrome HERE.
Endocrine. 2017 Aug 23. doi: 10.1007/s12020-017-1394-2. Association of obesity and diabetes with thyroid nodules.