Thyroid function is an essential part of our overall health, and making the right nutritional adjustments is key to keeping things optimal. Whether you have a thyroid condition or not, the foods you eat can affect your thyroid function in a big way.
The thyroid is a small butterfly-shaped gland located in the neck, that produces hormones that regulate metabolism, growth, and development. In hypothyroidism, the thyroid gland produces insufficient hormones, while Hashimoto's disease is an autoimmune disease where the body's immune system targets the thyroid gland, resulting in inflammation and decreased hormone production.
The most common cause of hypothyroidism (in areas of the world where iodine deficiency is not a concern) is Hashimoto’s thyroiditis, accounting for ~90% of cases.
While you may have heard differently from your doctor, nutrition plays a critical role in the management and treatment of both hypothyroidism and Hashimoto's disease. Making tailored dietary changes can be one way that you naturally support your thyroid health, reduce symptoms, and take control of your health.
Trust me, between my personal thyroid healing journey and witnessing hundreds of women implement these simple yet effective recommendations, you too can feel and function like a brand-new person.
Let’s dive in!
Iodine is an essential mineral required for the production of thyroid hormones. Therefore, inadequate iodine intake can result in hypothyroidism. The recommended daily intake of iodine is 150 micrograms for adults. Iodine-rich foods include seaweed, fish, shrimp, dairy, and eggs. However, if you have Hashimoto’s, more is not always better. Excess iodine may trigger an autoimmune flare so be mindful of consuming too much iodine-rich foods and supplementing beyond the recommendation for adults. Always work with your healthcare provider before trying new supplements.
Selenium is another mineral that's essential for thyroid function. It helps convert inactive thyroid hormone to its active form, and also has antioxidant properties that protect the thyroid gland from oxidative stress. Good sources of selenium include Brazil nuts, tuna, sardines, and eggs. Just don't go crazy with the Brazil nuts, or you'll end up with a selenium overdose (yes, that's a thing), 1-2 Brazil nuts daily is plenty.
Protein is essential for thyroid hormone synthesis and adequate protein in your diet is crucial for maintaining proper thyroid function. Prioritizing protein can also help support a stable appetite, steady blood sugar levels, and assist with healthy weight loss. Good sources of protein include lean meats, beef, fish, poultry, beans, legumes, and high-quality protein powders.
Fiber helps regulate digestion and prevents constipation, a common symptom of hypothyroidism. Fiber is also fuel and nourishment for a healthy microbiome; another important area to support if you have Hashimoto’s. Some of my favorite high-fiber foods include berries, avocados, beans, apples, carrots, greens, broccoli, nuts, and seeds. Aim for > 30 g daily; your gut (and your thyroid) will thank you.
Goitrogens are naturally occurring substances that can interfere with thyroid hormone production by reducing iodine uptake by the thyroid gland. Goitrogenic foods include cruciferous vegetables like broccoli, cauliflower, and cabbage, as well as soy-based products. Don't worry, you don't have to give up these foods entirely, you can reduce the goitrogenic levels in these foods significantly through cooking. In fact, you would need to consume a high level of these foods in their raw state to negatively influence thyroid function and many of these vegetables have liver-supportive and antioxidant boosting properties.
Processed foods are often high in refined carbohydrates and unhealthy fats, which can lead to weight gain and insulin resistance. These factors can exacerbate hypothyroidism symptoms as well. Therefore, it’s best to avoid processed foods and focus on whole, nutrient-dense foods a majority of the time.
Studies have shown that individuals with Hashimoto's disease may benefit from a gluten-free and dairy-free diet. Gluten is a protein found in wheat, barley, and rye, and some people with Hashimoto's disease may have an autoimmune response to gluten, worsening their symptoms. Similar to gluten, proteins found in dairy can also trigger the autoimmune response and exacerbate symptoms and inflammation. Many adults are also lactose-intolerant, making it difficult to digest dairy properly leading to digestive distress. So if you're struggling with symptoms despite making other dietary changes, it might be worth giving gluten and dairy-free a try.
Caffeine may seem like a great way to boost energy when you’re dealing with chronic fatigue, but it’s not the wisest choice for those with thyroid disease. Caffeine can interfere with the absorption of thyroid medications, so it’s important if you do consume caffeine to wait for at least 60 minutes after taking your medication. When caffeine is consumed at the same time as thyroid medication, it can reduce the medication's effectiveness by up to 36%! Caffeine can also negatively impact adrenal function and stress hormones, which can result in unstable blood sugar levels, weight gain, and sleep disruption. If you choose to continue drinking caffeine, enjoy it with or after a balanced breakfast, avoid drinking after noon, and be sure to hydrate well with water throughout the day.
A common pitfall I see with individuals living with hypothyroidism and Hashimoto’s is chronic yo-yo dieting and restrictive eating. When a person consumes too few calories, their body may not have enough energy to produce adequate levels of thyroid hormones, which can lead to a condition known as "low T3 syndrome" or "euthyroid sick syndrome." This is where T3 (active thyroid hormone) levels are abnormally low, but T4 levels remain normal. Low T3 levels can negatively impact metabolism, energy levels, and overall health. When T3 levels are low, the body's metabolic rate slows down, making it harder to lose weight and easier to gain weight. This can result in symptoms such as fatigue, weakness, and difficulty concentrating. Work with a Registered Dietitian to help determine a healthy calorie level and a sustainable way to lose weight with hypothyroidism and Hashimoto’s.
Try incorporating these changes into your lifestyle and see the impact that they make! You will likely learn a lot about how your body responds to your diet and notice steady improvements overtime. Remember, you have more influence over your health than you may think, start with these basics and master them. The results will speak for themselves!