Vitamin D & the Thyroid: Why you must test your vitamin D levels if you have thyroid disease
Updated: May 13
Vitamin D is very important for overall wellness, as well as strong and healthy bones. Your body can actually make its own vitamin D upon exposing your skin to sunlight, but vitamin D can also be found in supplements and in very small amounts in some foods.
Vitamin D has been found to support many aspects of the body including:
- Immune function
- Muscle function
- Cardiovascular function
- Inflammatory processes
- Brain development
- Anti-cancer effects
Unfortunately, vitamin D deficiency is now a known global health problem. Over 1 billion people worldwide are estimated to be insufficient or deficient in vitamin D!
Low levels of vitamin D in the body have been associated with:
- Vascular disease
- Chronic inflammation
- Increased risk and severity of thyroid disease
- Increased viral infections
- Increased TSH and reduced T3
Of course, I was particularly interested in learning more about how vitamin D levels could affect thyroid levels.
In a recent study conducted by Dr. Amal Mohammed Husein Mackawy, it was found that low vitamin D status in patients corresponded with higher TSH levels and lower T3 levels (the active thyroid hormone).
Another study found that when adjusted for age, presence of thyroid antibodies was inversely correlated with vitamin D (lower vitamin D levels = higher levels of thyroid antibodies). Other evidence suggests that vitamin D deficiency is more common among individuals with thyroid cancer or thyroid nodules, compared to the general population.
Even more interesting, receptors for vitamin D are found within the thyroid gland! And, even if you don’t have known thyroid disease but you have some elevated inflammation, the increased inflammatory response in the body can lower levels of thyroid hormones!
Many of my patients over the years have assumed that because they spend time outdoors, or supplement with vitamin D on a regular basis, their levels are adequate. Unfortunately, this is often not true. Many of these patients’ vitamin D levels were still too low upon testing vitamin D status via a blood test.
That said, it can be dangerous to have too much vitamin D in your body as well, so it is very important to have your vitamin D levels testing and ensure you are in the optimal range!
What’s your experience with vitamin D? Have you had your levels checked? Do you supplements regularly? Leave your comments below ☺
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