If you are one of 20 million people with a thyroid dysfunction (and that’s just in the US of A, my phenomenal friends), then you’ve probably read a lot of articles and social media posts on what you should or shouldn’t eat to improve your symptoms. These recommendations can vary drastically based on if you’re searching “Hashimoto’s” or “hypothyroidism.” So let’s look at why nutrition can be helpful with thyroid dysfunction, and what actual research and clinical experience shows when it comes to supporting your thyroid health.
You know an organ is pretty special when it’s shaped like a butterfly. True story. This small gland is housed in your neck region, just below the Adam’s Apple. It releases hormones that help regulate metabolism, thus controlling the heart, other muscles, digestion, brain development, and bone health to name a few. These friendly hormones are mostly made from iodine, a mineral, and tyrosine, an amino acid. Unfortunately, environmental factors, such as stress and food, and genetics can dysregulate the production and function of these hormones. This may lead to hypothyroidism (decreased metabolism) or hyperthyroidism (increased metabolism). In some instances, the body starts to attack the thyroid, resulting in the autoimmune diseases Hashimoto’s (decreased metabolism) and Grave’s (increased metabolism). For simplicity purposes, I’m focusing on Hashimoto’s and hypothyroidism today, which are the most common thyroid conditions, and are associated with symptoms of decreased metabolic function (fatigue, cold sensitivity, constipation, dry skin, weight gain, thinning hair, muscle weakness, etc.).
Without further ado, here are the recommendations:
Go Mediterranean. Incorporate plenty of vegetables, fruit, beans, whole grains, quality protein, and healthy fats (avocado, olive oil, olives, nuts, seeds, etc). Studies have shown that processed meats and artificial sweeteners negatively affect thyroid function, so limit hotdogs, sausages, and the like, while opting for real sweeteners when consuming sweet treats (i.e. fruit, honey, maple syrup, coconut sugar, sugar, etc.).
Cook Cruciferous. Raw cruciferous vegetables such as broccoli, cauliflower, Brussel's sprouts, cabbage, and kale contain goitrogens, which interfere with thyroid hormone production and utilization. Have no fear. Simply cook these vegetables and it deactivates the goitrogens. Phew!
Watch Your Soy. Soy is also a goitrogen, but more importantly, it can inhibit the absorption of some thyroid medications. I encourage you to ask your health practitioner, or read your medication’s label to see if it says to limit or avoid soy consumption.
To Be or Not To Be Gluten-Free. Many individuals with Hashimoto’s also have another autoimmune condition known as Celiac disease (the body attacks itself when exposed to gluten, a protein found in wheat, rye, etc.). If you have Celiac disease, the only treatment is to eat gluten-free. Because of this common coexistence, many practitioners recommend a gluten-free diet; however, researchers have mixed feelings on this recommendation. Studies have found that adhering to a gluten-free diet in the absence of Celiac disease may cause more stress, and thus, decreased quality of life. However, multiple studies have found that eating gluten-free decreased thyroid antibodies, increased vitamin D levels (which we’ll discuss later), and decreased inflammation in individuals who didn’t have Celiac disease. This is mostly attributed to better nutrient absorption of key minerals and vitamins that support thyroid health (i.e. iodine, selenium, zinc, vitamin D). What does this mean for you? First, get checked for Celiac disease if you have Hashimoto’s, and second, pay attention to how you feel when you consume gluten. The one thing researchers do agree on is to at least consume a low gluten diet if you don’t have Celiac disease (if you do have Celiac disease, gluten-free is the only way).
Iodine. Iodine plays a major role in thyroid function and making thyroid hormones. Excessive amounts of this mineral have been associated with Hashimoto’s and goiter, while deficiency is associated with hypothyroidism. For this reason, it’s recommended that you don’t supplement iodine with Hashimoto’s. For all other thyroid conditions, it’s recommend to test your iodine levels to know if you need to incorporate more iodine-rich foods. Foods rich in iodine include seaweed like dried kelp, iodized salt, cod, and yogurt. In certain circumstances, supplementation may be necessary and should be discussed with your health practitioner.
Selenium. Selenium is another mineral that’s important in the production of Triiodothyronine (T3), which is the “active” thyroid hormone. Fun fact: the thyroid gland has the highest selenium content per gram of tissue. If that wasn’t cool enough, it also has antioxidant and anti-inflammatory properties, which are very helpful with Hashimoto’s. Foods that are rich in selenium include Brazil nuts, wild-caught salmon, tuna, poultry, cottage cheese, halibut, navy beans, eggs, sunflower seeds, mushrooms, grass-fed beef, and oats. Again, it’s important to test your levels to see if you are deficient. If you are deficient, and iodine is normal, then eating more selenium-rich foods or supplementing with selenium is recommended. But don’t just use any selenium if you need to supplement. Researchers found that selenomethionine is the preferred supplement to support thyroid health; however, it’s always important to work with your health practitioner to determine what is best for you.
Zinc. Zinc is another mineral that helps with making thyroid hormones, but here’s the double whammy. Thyroid function also influences zinc metabolism. So, what came first? Chicken or the egg? And does it matter? Researchers found that adequate zinc levels reduced thyroid antibodies in individuals with Hashimoto’s. They also found that zinc positively improved T3 production. Another study also associated an improvement in thyroid-induced hair loss when supplementing with zinc. As always, I like to take a food-first approach over supplementing. Foods rich in zinc include lamb, pumpkin seeds, hemp seeds, grass-fed beef, chickpeas, and lentils.
Vitamin D. Vitamin D is a fat-soluble vitamin and steroid hormone that has anti-inflammatory and immune-supporting properties that positively help those with Hashimoto’s. Again, the cause and effect of this relationship is unknown. Does a deficiency in vitamin D predispose someone to Hashimoto’s, or does Hashimoto’s lead to vitamin D deficiency? One thing is for sure though: supplementing vitamin D significantly reduced levels of thyroid antibodies. It has also been associated with improving thyroid function in general. This is a vitamin and hormone that many of us are deficient in due to lack of sun exposure, and it can be hard to make-up for that deficiency through food sources alone. However, it’s important to check levels and get guidance from your health practitioner before supplementing. Food sources rich in vitamin D include cod liver oil, wild caught salmon, mackerel, and tuna.
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With love, Steph
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