For the estimated 20 million adults in the United States with some form of thyroid disease, diet can make a big difference in how you feel and your overall health. Certain nutrients help support thyroid function, while others can interfere with its activity. To help you navigate the best dietary choices, we spoke with healthcare experts about the best food for thyroid patients.
What does your thyroid do?
The thyroid is a small, butterfly-shaped gland located in your neck. “[It] plays a critical role in regulating metabolism, energy and hormone production,” explains Brooke Taylor, MCN, RDN, Lead Dietitian at RescueMD. When it’s under active (hypothyroidism), you may experience fatigue, weight gain and sluggishness. When it’s overactive (hyperthyroidism), symptoms can include weight loss, anxiety and rapid heart rate.
Do you have (or suspect you have) a thyroid condition?
How diet affects thyroid health
While medication is often necessary for managing thyroid conditions, a balanced diet can have a big impact. “Eating a diet rich in whole foods that includes a variety of vegetables, fruits, nuts, whole grains, lean protein and healthy fats can help support thyroid function,” says Dawn Manning, MS, RD, CDCES, Dietician and Nutrition Expert with Nutu App.
But before we talk about diet, we need to first look at the smaller picture—what makes certain foods better? “Certain nutrients support thyroid function, particularly the production of thyroid hormones,” notes Taylor. Below are some key nutrients that play starring roles:
- Iron: “Iron is essential for the synthesis of thyroid hormones,” says Taylor. “An iron deficiency can lead to low thyroid hormone levels and cause fatigue and other thyroid-related symptoms.”
- Iodine: “[Iodine] plays a role in making the thyroid hormones thyroxine and triiodothyronine,” says Manning. A deficiency can lead to hypothyroidism.
- Selenium: “Selenium is crucial for the conversion of [a hormone called] T4 (the inactive form) into T3 (the active form) in the body,” says Taylor. “It also acts as an antioxidant, protecting the thyroid gland from oxidative damage.”
- Zinc: “[Zinc] helps thyroid hormone production and supports the immune system,” says Manning.
The best food for thyroid patients
To help optimize thyroid health, incorporate these nutrient-dense foods into your diet:
1. Seaweed and iodized salt
Iodine is essential for thyroid hormone production. Natural sources of iodine include seaweed (such as nori, dulse and kelp) and iodized salt. However, too much iodine can be problematic, so moderation is key. Taylor says the recommended intake for adults is 150 mcg.
2. Brazil nuts
Brazil nuts are one of the richest sources of selenium, a mineral crucial for thyroid hormone metabolism and protection against oxidative stress. Just one to two Brazil nuts a day can provide your daily selenium needs.
“[Selenium] also helps protect the thyroid from oxidative stress, which is particularly important in autoimmune thyroid disorders” such as Hashimoto’s disease or Grave’s disease, says Taylor. Bonus: Brazil nuts also contain zinc, which further supports thyroid health.
3. Fatty fish
Fatty fish like salmon, sardines and mackerel are rich in omega-3 fatty acids and vitamin D. “Omega-3 fatty acids have anti-inflammatory properties that can benefit those with autoimmune thyroid disease by reducing inflammation and improving immune function,” says Taylor.
However, certain types of fish with high mercury content can be harmful to thyroid health. Taylor notes that mercury is a “heavy metal that can disrupt thyroid function, and excessive exposure can lead to thyroid disease.” It’s best to limit your intake of swordfish, tilefish and king mackerel.
4. Dairy products
Many thyroid patients, particularly those with hypothyroidism, may have low vitamin D levels. Dairy products such as yogurt, cheese and milk provide vitamin D, calcium and iodine, all of which are beneficial for thyroid health.
“Vitamin D deficiency has been linked to thyroid autoimmune diseases,” says Taylor. “Ensuring adequate vitamin D levels supports thyroid function, immune health and reduces inflammation.”
5. Leafy greens
Leafy greens such as spinach, kale and Swiss chard provide essential nutrients like magnesium, which supports thyroid function and helps regulate metabolism. They also tend to be rich in thyroid-supporting iron.
However, those with hypothyroidism should consume cruciferous vegetables (think broccoli, cabbage and kale) in moderation, as excessive amounts may interfere with iodine absorption. Instead, Taylor says “cooking these vegetables significantly reduces their goitrogenic effects,” or their ability to interfere with thyroid hormone production, as opposed to eating them raw.
One more note about fiber: Don’t consume too much. “While fiber is an essential part of a healthy diet, excessive fiber can interfere with the absorption of thyroid medications,” says Taylor. Aim for 25 grams daily for women and 30 grams for men.
Thyroid foods to avoid or limit
Some foods can negatively affect thyroid function, particularly in people with existing thyroid issues.
- Soy. “If you take thyroid hormone medication, don’t eat soy right before taking it, as it may interfere with absorption,” advises Manning. Soy can be found in tofu, soy milk, tempeh, edamame and soy protein-based products.
- Processed foods. “High-fat foods may interfere with absorption of thyroid replacement medication,” Manning adds. These foods can also contribute to inflammation and weight gain.
- Gluten. Some thyroid patients with Hashimoto’s disease have gluten sensitivities or celiac disease. Consuming it may exacerbate autoimmune reactions in those people. In some cases, following a gluten-free diet may be recommended.
If you suspect thyroid issues, talk to a healthcare professional to determine the best dietary approach for your specific needs. By incorporating the right foods and limiting potential triggers, you can help keep your thyroid functioning optimally and feel your best.
This content is not a substitute for professional medical advice or diagnosis. Always consult your physician before pursuing any treatment plan.