Nutrition for Hypo vs Hyper Thyroid Disease

The food we choose to eat has a direct impact on our body’s immune function, and overall vitality—including our thyroid hormones. Hippocrates coined the phrase “let food be thy medicine and medicine be thy food” for good reason.  

Different foods contain various types of nutrients and phytochemicals that essentially provide our immune system with the instructions needed to function either properly or improperly depending on what we eat. So, it really is important to “eat the rainbow” since there are a wide-variety of disease-fighting phytochemicals (compounds produced by plants) in different colored fruits, vegetables, grains, beans, and other plants (e.g., carotenoids in yellow & red foods, chlorophylls in green foods, and anthocyanins in blue, purple, and red foods).

Hypothyroidism occurs when the thyroid gland is underactive and not enough thyroid hormone is produced. Hyperthyroidism is the opposite when the thyroid gland is overactive and excess thyroid hormone is produced. Certain foods affect the thyroid gland in specific ways, either supporting or inhibiting (blocking) thyroid function.

 

NUTRIENTS – HYPOTHYROIDISM:

Research has shown that several nutrients are important for optimal thyroid health. For those suffering from an underactive thyroid, the minerals iodine, selenium, and zinc can be supportive. Iodine can be found in sea vegetables, fish, dairy products, eggs, and iodized salt. Selenium activates thyroid hormones for the body to use and acts as a potent antioxidant to help protect the thyroid gland from damaging molecules known as free radicals. Selenium can be found in Brazil nuts, fish, eggs, and beans. Zinc also helps activate thyroid hormones and supports immunity. Zinc sources include oysters, shellfish, beef, and chicken. It is important to talk to a qualified healthcare professional before choosing to take dietary supplements containing these minerals (excessive amounts can also cause harm).

Goitrogens are compounds found in certain foods that can interfere with thyroid hormone function. They are abundant in soy products, cruciferous vegetables (i.e., cabbage, broccoli, kale, cauliflower, spinach, etc.), fruits and starchy plants (e.g., sweet potato, cassava, peaches, strawberries, etc.), nuts & seeds (e.g., millet, pine nuts, peanuts, etc.), and coffee, green tea, and alcohol. Some people with an underactive thyroid may benefit from limiting goitrogenic foods or cooking them thoroughly to inactivate these compounds.

NUTRIENTS – HYPERTHYROIDISM:

An overactive thyroid usually requires treatment such as, medication, radiation therapy, or surgery. However, certain foods can reduce the negative effects of excess thyroid hormone. Eating cruciferous vegetables can help inhibit thyroid hormone by blocking iodine uptake in the thyroid gland. Bamboo shoots, bok choy, broccoli, Brussels sprouts, cauliflower, collard greens, kale and mustard greens are good sources.

A low-iodine diet can also be beneficial. Foods that are low in iodine include: non-iodized salt (sea salt), coffee or tea without dairy or soy-based creamers, egg whites, fresh or canned fruits, and unsalted nuts & nut butters. Avoiding dairy products, egg yolks, seaweed, seafood additives, fish, and shellfish is important to prevent consuming too much iodine. Gluten, soy, and caffeine should also be avoided to prevent inflammation and the potential for worsening hyperthyroid symptoms, such as anxiety, nervousness, irritability, and rapid heart rate.

Iron, selenium, zinc, calcium, and vitamin D can be supportive for an overactive thyroid. Low iron levels have been associated with hyperthyroidism. Heme iron sources are more readily absorbed by the body and can be found in red meat, and poultry. Non-heme iron is less readily absorbed and can be found in plant sources (e.g., beans, leafy greens, lentils, nuts, seeds, and whole grains). Selenium and zinc are important to balance thyroid hormone levels and protect the thyroid gland (see above section under Nutrients Hypothyroidism for details). Calcium and vitamin D are important for immune function, and to build strong healthy bones. Excess thyroid hormone can lead to weak and brittle bones that can break easily. Food sources of calcium include spinach, collard greens, white beans, kale, okra, and almond milk. Vitamin D sources that are also low in iodine include beef liver, mushrooms, and fatty fish. Fortified foods like cereals and orange juice are usually processed and not always a good source to obtain these nutrients since they often contain added sugars and filler ingredients.

Healthy non-dairy fats from whole food sources are also important to protect the thyroid gland. Sources include flaxseed oil, olive oil, avocado oil, coconut oil, avocado, and unsalted nuts and seeds. Other helpful anti-inflammatory compounds can be found in spices like turmeric, green chili, and black pepper.

Farrah Shahin, MS

Certified Nutrition Specialist®

 

Resources:

https://lpi.oregonstate.edu/mic/dietary-factors/phytochemicals

https://www.healthline.com/nutrition/eat-the-rainbow

https://www.healthline.com/nutrition/hypothyroidism-diet#important-nutrients 

https://lpi.oregonstate.edu/mic/food-beverages/cruciferous-vegetables

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3650504/#:~:text=Three%20major%20classes%20of%20phytochemicals,%2C%20purple%2C%20and%20red

https://www.healthline.com/health/hyperthyroidism-diet

By Valhalla Wellness & Medical Centers

August 12, 2022