Our immune system does much more than guard against colds and flu. Yes, it works to fight germs and harmful bacteria, but it also determines which cells are good and bad. If the immune system is not balanced correctly, it can essentially turn against its own cells, resulting in an autoimmune disease. There are more than 100 autoimmune diseases, and it is estimated up to 8% of people globally are affected by one or more of them. [1]

One of the most prevalent autoimmune disorders in the world today is Hashimoto’s thyroiditis, which accounts for 90% of hypothyroid cases. This disease is caused when the body’s immune system attacks the thyroid gland in the neck, which is an important gland for making vital hormones to ensure the proper functioning of the body.

While there is currently no cure for Hashimoto’s thyroiditis, there are promising treatments shown to normalize hormones, improve the immune system, and even aid in regulating metabolism that might be thrown off due to this disease. Even more promising is the help therapeutic doses of micronutrients like Vitamin D provide.

Vitamin D is a micronutrient that is produced within the body and through the synthesis of sunlight. We can boost Vitamin D by taking supplements. Healthy Vitamin D levels are critical, because every single cell requires it to function, and Vitamin D plays multiple roles within the body. For instance, the combination of Vitamin D with calcium is essential for growing healthy and strong bones, and it even helps in decreasing inflammation within the body. Vitamin D plays a role in the growth of cells, and it actually helps regulate the entire immune system.

Specifically, normal levels of Vitamin D ensure the immune system’s regulatory T cells do their job. T cells communicate with B cells, which then produce antibodies. If we lose normal levels of Vitamin D, T cells stop communicating, creating a downstream issue which eventually leads to chaos in the immune system and autoimmune disorders.

Within the last decade, a deficiency of this important vitamin has been noted in patients with Hashimoto’s thyroiditis. One study in particular divided 42 women with Hashimoto’s thyroiditis into two groups – one that took a placebo, and one that took a Vitamin D supplement of 50,000 IU weekly for three months. At the end of the study, scientists found both anti-thy-roglobulin antibodies and thyroid-stimulating hormones significantly decreased in the control group, leading them to report Vitamin D can help in decreasing Hashimoto activity within the body.

Another similar research study was conducted on 75 patients with Hashimoto’s to see what effect Vitamin D had on the disease. After eight weeks of treatment and supplementation with Vitamin D, the thyroid autoantibodies were decreased.

Because the deficiency of Vitamin D is so prominent in those with Hashimoto’s thyroiditis, supplementing it in patients who are struggling with hypothyroidism can prove to be beneficial. Part of the study even demonstrated a decrease in the risk factors associated with cardiovascular disease as well, so Vitamin D supplementation is certainly an option to consider across multiple realms.

Your functional medicine practitioner will offer Vitamin D as an effective tool to support your immune system and guard against autoimmune diseases like Hashimoto’s thyroiditis. At Red Tail Wellness Centers, we base dosage on your current levels of Vitamin D, level of inflammation and how your body responds to therapy. We then rerun lab analysis after 8 weeks to ensure effectiveness. Ultimately, these therapeutic doses should increase your level of Vitamin D and your health should improve!


[1] https://www.ncbi.nlm.nih.gov/pubmed/31841960
[2] https://www.mayoclinic.org/diseases-conditions/hashimotos-disease/symptoms-causes/syc-20351855