The Best Diet For Hyperthyroidism: What To Eat And Avoid

Hyperthyroidism is a common condition affecting 1% of the American population over the age of 12.  An overactive thyroid causes uncomfortable symptoms, such as sudden weight loss, anxiety, hand tremors, difficulty sleeping, and frequent bowel movements.¹

Diet can potentially improve or worsen symptoms of several conditions, including hyperthyroidism. Let’s dive into the ideal diet for hyperthyroidism. 

What causes hyperthyroidism?

Hyperthyroidism is where your thyroid gland produces excessive thyroid hormones. It is also known as an overactive thyroid. 

Several conditions cause hyperthyroidism, but Graves’ disease is the most common. Four out of every five Americans with hyperthyroidism have this condition.²

Graves’ disease and other conditions that cause hyperthyroidism, such as Plummer’s disease, often have a genetic influence. Some cases of hyperthyroidism can also be attributed to thyroid inflammation, too much iodine in the diet, or certain medications. 

What are the symptoms of hyperthyroidism?

Some of the symptoms include:

• Fatigue

• Sleeplessness

• Heat intolerance

• Irregular heartbeat

• Sudden weight loss

• Unstable bowel movements

• Unpredictable mood 

• Bulging eyeballs

• Hand tremors

Hyperthyroidism: Why is diet so important?

Adjusting your diet to increase or decrease your intake of certain foods, nutrients, and minerals is a vital step toward managing hyperthyroidism. The foods we eat can influence thyroid hormone release and thyroid functioning.

What is the best hyperthyroidism diet?

A low-iodine diet is one of the most relevant factors that can reduce hyperthyroidism symptoms. The most commonly known nutrients and chemicals that can affect hyperthyroidism are:

• Iodine promotes thyroid hormone production 

• Calcium and vitamin D can prevent bone density reduction caused by hyperthyroidism

• Caffeine can worsen pre-existing symptoms of hyperthyroidism

Foods to avoid with hyperthyroidism

Iodine-rich foods

Iodine promotes the secretion of thyroid hormones from the thyroid gland, worsening the symptoms if consumed in large amounts. Foods that are rich in iodine include:

• Fish (particularly shellfish)

• Egg yolks

• Dairy products

• Seaweed or kelp

• Red food dye

• Molasses

• Carrageenan (an additive that thickens and preserves foods and drinks)

• Iodized salt, iodine supplements, and any baked goods containing sodium iodate

Soy products

You should avoid soy if you’re undergoing radioactive iodine treatment to regulate thyroid hormone production. Foods to avoid include:

• Soy sauce

• Soy-based milk

• Tofu

• Soybean oil

• Edamame beans

• Alternative creamers containing soy

Gluten

Research has suggested hyperthyroidism is more common among people with celiac disease (gluten intolerance). It is beneficial to restrict the consumption of foods that may contain:³

• Wheat (bread, cereals, cookies)

• Barley (soups, food coloring, protein bars)

• Yeast ( beer, bread, cakes, pretzels, buns)

• Malt (beer, whiskey, bagels)

• Rye (beer, gravy, cold cuts, french fries)

• Triticale (deli meats, ice cream, ketchup, and mustard)⁴

Caffeine

If you have hyperthyroidism symptoms, such as trembling, anxiety, difficulty sleeping, or irritability, foods, and drinks containing caffeine can worsen them. You should avoid the following:

• Coffee

• Chocolate 

• Guarana-based energy drinks

• Regular sodas

Foods to eat in a hyperthyroidism diet

Including the following foods, minerals, vitamins, fats, and spices in your diet can manage your hyperthyroidism symptoms.

Foods low in iodine

Doctors may advise some people with hyperthyroidism to follow a low-iodine diet consisting of foods such as:

• Non-iodized salt

• Vegetables (particularly cruciferous)

• Fresh or canned fruit

• Jams or jellies

• Potatoes

• Vegetable oils

• Honey

• Modest servings of chicken, beef, turkey, lamb, or veal

Cruciferous vegetables

Cruciferous vegetables contain compounds that partially inhibit the thyroid gland’s production of hormones. This may reduce iodine uptake in the thyroid, slowing down the overproduction of these hormones. Vegetables that you should include in your diet are:

• Bok choy

• Broccoli

• Cabbage

• Cauliflower

• Collard greens

• Brussels sprouts

• Kale

• Arugula

• Rutabaga

• Cassava

• Bamboo shoots

Vitamins and minerals

Selenium

Studies have found that the micronutrient selenium seems to delay the progression of diseases that cause hyperthyroidism, such as Graves’ Disease. It may also mitigate symptoms such as bulging eyes.⁵

Your thyroid requires selenium to metabolize its hormones, so you may need to take selenium supplements. Nevertheless, some foods can help with selenium uptake, including:

• Brazil nuts

• Oatmeal

• Spinach

• Egg whites

• Baked beans

• Pasta and cereals (fortified)

• Mushrooms

Other foods rich in selenium may also contain high levels of iodine, which can potentially affect the thyroid. These foods include tuna, shrimp, ham, cottage cheese, egg yolks, and halibut. You should consult a medical professional to determine the best diet for you.

Iron

Iron is essential for many bodily processes, including red blood cells sending oxygen around the body. Low iron intake is the most common nutritional deficiency worldwide, and research has linked it to thyroid disorders, including hyperthyroidism. For these reasons, it is important to include iron-rich foods in your diet, including:⁶

• Dark chocolate

• Beef, chicken, turkey, or pork

• Spinach (fresh)

• Nuts, seeds, and whole grains

• Lentils

• Dry beans

• Leafy greens

Calcium and Vitamin D

Research has linked hyperthyroidism to weak bones and a higher fracture rate. It’s important to have enough calcium and vitamin D in the diet, as these promote healthy bones. Some calcium-rich foods include:

• Almond milk

• Spinach

• Yogurt

• Kale

• Bok choy

• Broccoli

The most effective way for the body to produce vitamin D is through sun exposure, which can present issues for people in areas where there isn’t much sunlight. However, you can also get vitamin D from food.

Foods containing vitamin D but high in iodine include salmon, tuna, milk, fortified dairy, and cereal-based products. If you’re undergoing iodine therapy, stick to:

• Vitamin D-fortified orange juice and cereals

• Beef liver

• Mushrooms 

Fats

Eating plenty of healthy fats is very important if you consume a non-dairy diet. Healthy fats protect against thyroid inflammation by balancing thyroid hormone levels. Sources of healthy fats include many types of oils, such as:

• Flaxseed

• Olive

• Avocado

• Coconut

• Unsalted nuts 

Spices

Research has linked a handful of spices to reducing hyperthyroidism thanks to their anti-inflammatory properties. Used to flavor dishes, these spices could boost your thyroid’s healthy function:⁷

• Turmeric 

• Green chili peppers

• Peppercorns

Nutrition and supplements

Dietary supplements can sometimes contain high levels of iodine without you being aware of it. Speak to your medical professional about the supplements you take for peace of mind.

The lowdown

Hyperthyroidism is a disorder caused by genetic and environmental factors and involves the overproduction of thyroid hormones T3 and T4. Hyperthyroidism can be managed through some strategies, one of which is dietary changes.

Consult medical professionals and dietitians to arrange a plan that suits your case. It’s best to enjoy homemade meals and avoid iodized and processed foods. Sometimes you may need supplements as an alternative, but your doctor will be able to advise you accordingly.