When it comes to your thyroid, most of know that iodine has a huge role to play in ensuring its health. But how about the sunshine vitamin, vitamin D? Vitamin D
is popularly known for its role in bone health, and if we’re feeling down in the dumps when the days grow shorter we often reach for a supplement top-up, but new research is also beginning to show a strong link between a deficiency in this vitamin and poor thyroid health. Could a lack of vitamin D be a factor in your thyroid issues?
What Is The Thyroid Anyway?
The thyroid is a very important hormone gland that plays a role in the conversion of the food you eat into energy (known as metabolism), and in the development and maturation of your body. The thyroid produces three hormones, which you may recognize if you’ve had blood tests done to access your thyroid; triidothyronine (T3), thyroxine (T4), and calcitonin. Calcitonin is involved in bone metabolism, while T3 and T4 are two hormones used in every single cell of the body in order to produce energy. T3 and T4 are made up of the amino acid tyrosine linked to 3 or 4 iodine molecules respectively. Put simply, if T3 (the active thyroid hormone) is out of balance then energy levels will likely reflect that.
An overactive thyroid, called hyperthyroidism, means too much T4 is produced, and results in symptoms like hot flashes, weight loss, hair loss, nervousness/ hyperactivity, emotional instability and/or restlessness. There are few known reasons for hyperthyroidism, but one cause is Grave’s disease. This is an autoimmune disorder which causes the thyroid gland to produce too much thyroid hormone. An autoimmune disorder develops when the immune system starts attacking healthy tissues. It’s not entirely clear yet why this happens; it’s thought to have a genetic component, but it may also be a case of nutritional deficiency and/or an allergy or intolerance.
Too little thyroid hormone can result in hypothyroidism, which causes body functions to slow down. An underactive thyroid can be genetic or develop from a deficiency in iodine. Hashimoto’s thyroiditis, another autoimmune disorder, can cause hypothyroidism. Hashimoto’s is chronic inflammation of the thyroid which in turn causes underactivity. Symptoms include general loss of energy, slow metabolism, being overweight, sensitivity to cold, slow pulse, dry hair, and in some cases depression.
How Does Vitamin D Play In To A Thyroid Disorder?
Let’s just take a quick step back and look at why we need vitamin D. This is an extremely important component in our health. It acts as a messenger in many processes every single second of the day, including control cell growth, immune function, the reduction of inflammation, and of course acts in the formation and maintenance of our bones. For these reasons, it’s known as an honorary hormone.
There are two ways we can get vitamin D naturally, (1) from exposure to sunlight. When UV light hits our skin the production of vitamin D begins, and 2) from our diet. Foods like fatty fish (salmon, sardines), eggs and shiitake mushrooms will also begin the long production process (for more on how our body makes D3 – the active form of vitamin D, click here
). Although we have two methods of getting what we need, vitamin D deficiency is a global health problem, and it’s estimated that over one billion people have a vitamin D deficiency . There are a few reasons why a deficiency may be present, including a poor diet, living in the northern hemisphere, skin tone (a darker skin tone acts a natural sunscreen and slows down the production of the vitamin D), aging, higher than average body weight, genetic predisposition (which could slow down absorption), and covering up when you do go out.
Vitamin D Deficiency Is Linked To Thyroid Disorders
It seems like the issue lies in the role vitamin D has in managing immune function. Vitamin D deficiency is being linked to autoimmune disorders like rheumatoid arthritis, inflammatory bowel disease (IBD), multiple sclerosis , lupus, and even Type I diabetes. Research is starting to show that the connection between a vitamin D deficiency and autoimmune disorders also extends to the thyroid. (2
) One study was able to show that a deficiency in both vitamin D3 (the active form) and calcium was linked to hypothyroidism; and the bigger the deficiency the more severe the disorder, while another study found that patients with Hashimoto’s thyroiditis have lower vitamin D levels than healthy individuals. The same study also found that those with lower vitamin D levels had higher levels of anti-thyroid antibodies (the immune cells that are responsible for attacking the thyroid). (3
) Grave’s disease has also been linked to a deficiency. It’s also possible that a vitamin D deficiency may increase the risk of thyroid cancer according to scientists from McGill University. (4
The truth is, although a deficiency in this vitamin is being linked to issues in the thyroid, the mechanism isn’t entirely clear yet; is it that a deficiency is causing the disorder, or the disorder is causing a deficiency? To complicate the matter further, there does seem to be some cases where an underlying genetic issue may mean some people are unable to take up enough vitamin D even though there is plenty in the diet. So it could be that a thyroid disorder is caused by genetics, or by a deficiency – or possibly both.
What To Do
1. Ensure you get a regular intake of vitamin D through your diet. Including foods like eggs, fatty fish, liver, kidney, mushroom and dark leafy greens will give you a dose.
2. Ensure you get outside each day for at least 20 minutes. And if the weather permits, expose as much skin as possible – try 10-15 minutes before you need to cover up with sunscreen or clothes. In the colder and darker months, supplementation is a very good idea. Doses will vary according to your condition, age and size. Speak to your Naturopathic Doctor or Holistic Medical Doctor.
3. If you think you have a deficiency or what to know what your levels are, ask your medical or naturopathic doctor for a Vitamin D test.
3. Shaye Kivity, Nancy Agmon-Levin, Michael Zisappl, Yinon Shapira, Endre V Nagy, Katalin Dankó, Zoltan Szekanecz, Pnina Langevitz and Yehuda Shoenfeld: “Vitamin D and autoimmune thyroid diseases.
” Cellular & Molecular Immunology (2011) 8, 243–248; doi:10.1038/cmi.2010.73; published online 31 January 2011