Hypothyroidism, a condition caused by an underactive thyroid, can create a wide variety of symptoms, such as fatigue, weight gain, trouble tolerating the cold, and joint and muscle pain.
If you are currently living with hypothyroidism, medication is usually recommended, but what you eat can also play a crucial role in thyroid function. Certain foods can boost your energy levels and support optimal function, while others may have a negative impact.
In this guide, we dive into the best foods for thyroid health, plus which foods to avoid. Here’s what you need to know to transform your diet for optimal thyroid function.
What is Hypothyroidism?
The thyroid is a butterfly-shaped gland that wraps around the trachea, or windpipe. It produces and stores hormones that regulate how your body uses energy. The main hormones released by the thyroid are the active hormone triiodothyronine(T3) and the relative inactive hormone tetraiodothyronine (T4). These two hormones, which work together, are collectively referred to as thyroid hormone.
“Thyroid hormones regulate many functions in the body, including metabolism, energy, digestion, temperature regulation, mood and hair, skin and joint health,” says Sari Eitches, M.D., a double board-certified internist and integrative holistic medicine physician at Tower Integrative Health and Wellness in Los Angeles.
Hypothyroidism occurs when the thyroid gland produces insufficient hormones, causing bodily functions to slow down. It’s most commonly caused worldwide by iodine deficiency, says Dr. Eitches.
However, in the U.S., the most common cause of hypothyroidism is the autoimmune condition Hashimoto’s disease, says Marc Cillo, M.D., an endocrinologist with UTHealth Houston in Texas. Hashimoto’s causes the body’s immune system to attack the thyroid gland, resulting in damage that impairs thyroid hormone production, notes Dr. Cillo.
Hypothyroidism symptoms include:
- Weight gain
- Fatigue
- Weakness
- Depression
- Cold intolerance
- Constipation
- Menstrual irregularities
- Impaired memory
- Hair loss
- Slowed speech
- Slowed heart rate
Can Diet Help People With Hypothyroidism?
“Replacing low thyroid levels with a thyroid hormone medication (such as levothyroxine) is the best way to bring levels back to normal,” says Dr. Cillo. Depending on the underlying cause of hypothyroidism, diet can also play an important role in treatment, adds Dr. Eitches.
“For example, a gluten-free or low-gluten diet has been shown to decrease antibody levels in those with Hashimoto’s,” says Dr. Eitches. Antibodies are proteins the immune system makes to attack foreign invaders—or in the case of autoimmune diseases, its own tissues.
Interestingly, celiac disease (an autoimmune condition in which gluten triggers the immune system to attack the intestine) is more common in individuals with Hashimoto’s hypothyroidism, explains Dr. Cillo. In individuals with both conditions, cutting out gluten may help, but according to Dr. Cillo, this method has not been proven effective in those without celiac disease.
Because of the varied effectiveness of a gluten-free diet for individuals with Hashimoto’s but without celiac, it’s best to speak with your doctor about the appropriate path to take.
“We recommend a healthy, well-balanced diet, rich in fruits, vegetables, whole grains, legumes and lean meats,” says Dr. Cillo. Eating this way ensures appropriate intake of essential macronutrients (carbohydrates, proteins and fats) and micronutrients (vitamins and minerals). Research indicates that diets rich in fruits and vegetables and lower in animal proteins—like the Mediterranean diet—help protect against cellular damage in individuals with Hashimoto’s thyroiditis.
What Nutrients Are Important for People With Hypothyroidism?
According to Lauren Papanos, a registered dietitian specializing in thyroid disorders at Functional Fueling Nutrition, the following nutrients are important for thyroid health:
- Iodine
- Selenium
- Zinc
- Magnesium
- Iron
- Vitamin D3
- Vitamin B12
Foods to Eat If You Have Hypothyroidism
Individuals with hypothyroidism should incorporate the following foods into their diet:
Iodine
“Iodine is an essential mineral in the production of thyroid hormones,” says Dr. Eitches. While severe iodine deficiency can lead to hypothyroidism, excess iodine can be equally as problematic for the thyroid (potentially leading to hyperthyroidism), which is why Papapos emphasizes that it’s essential to get just enough.
Work with a health care provider to determine an iodine intake that’s appropriate for you. Food sources of iodine include:
- Fish like cod and tuna
- Shellfish
- Seaweed
- Milk
- Yogurt
- Cheese
- Eggs
- Iodized salt
Selenium
Selenium supports the thyroid in two ways, says Dr. Eitches. “It decreases antibody activity in individuals with Hashimoto’s and supports the conversion of T4 to T3,” she says. T3 is the active form of thyroid hormone that helps regulate metabolism and other functions in the body’s cells and tissues. The conversion of T4 to T3 helps ensure the proper balance of thyroid hormones in the body. Selenium-rich food sources include:
- Seafood
- Meat
- Poultry
- Eggs
- Milk
- Yogurt
- Cheese
- Whole grains
Zinc
Like selenium, zinc is essential for activating thyroid hormones, says Dr. Eitches. “Zinc deficiency has been shown to cause hypothyroidism and decreased metabolism,” she adds. Good food sources of zinc include:
- Oysters and other shellfish
- Meat
- Fish
- Poultry
- Fortified breakfast cereal
- Beans
- Nuts
- Whole grains
- Eggs
- Dairy products
Magnesium
Magnesium is important in the balance and production of thyroid hormones, says Papanos. She adds that very low magnesium levels are associated with abnormal thyroid function, potentially increasing the risk of hypothyroidism. Foods high in magnesium include:
- Legumes
- Nuts
- Seeds
- Whole grains
- Green leafy vegetables
- Milk
- Yogurt
- Cheese
- Fortified breakfast cereals
Iron
Just as iron is essential for thyroid hormone metabolism, iron deficiency can impair the process, says Dr. Eitches. You can get iron by eating the following foods:
- Lean meat, poultry or seafood
- Fortified breads and breakfast cereals
- Beans
- Peas
- Spinach
- Nuts
- Dried fruits, such as raisins
Vitamin D3
Vitamin D3 is obtained through food and made in the body after sun exposure, says Papanos. Research indicates that low levels of the nutrient are linked with autoimmune hypothyroidism.[2]
The following foods can help you get more vitamin D:
- Fatty fish, like salmon, tuna and mackerel
- Fish liver oil
- Beef liver
- Egg yolks
- Cheese
- Fortified breakfast cereals and orange juice
Vitamin B12
People who have hypothyroidism are more likely to be deficient in vitamin B12, a nutrient that’s important for blood and nerve health and energy production, says Dr. Eitches. Dietary sources of vitamin B12 include:
- Seafood, especially oysters and clams
- Poultry
- Meat
- Organ meats like beef liver
- Eggs
- Milk
- Cheese
- Yogurt
- Fortified breakfast cereals
Foods to Avoid or Limit If You Have Hypothyroidism
Just as some foods support thyroid health, individuals with hypothyroidism should limit others. They include:
Goitrogens, compounds found in foods like cruciferous vegetables and soy-based foods, have been shown to inhibit thyroid hormone synthesis—mainly by blocking iodine, says Dr. Eitches. Goitrogens are typically an issue for those with low iodine levels or when consumed in large, uncooked quantities, she says. Sources of goitrogens include broccoli, kale, cabbage and tofu.
Gluten should be avoided in individuals with Hashimoto’s who have also been diagnosed with celiac disease, advises. Dr. Cillo. Gluten is present in the grains wheat, barley, rye, and triticale (a blend of wheat and rye).
Ultra-processed foods and fatty foods, such as chips, baked goods, french fries and burgers increase oxidative stress and inflammation in the body, raising the risk and severity of autoimmune diseases like Hashimoto’s thyroiditis, says Dr. Eitches.
Research links:
https://pubmed.ncbi.nlm.nih.gov/21325465/
https://www.sciencedirect.com/science/article/abs/pii/S0160412011002716
https://academic.oup.com/nutritionreviews/article/74/4/248/1807251
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC501258/
Source: Forbes Health
Authors:
Heidi Borst
Michelle Routhenstein, M.S., R.D.N., C.D.E, C.D.N.
Nutrigenomics Institute is not responsible for the comments and opinions included in this article