Can Certain Foods Affect Your Thyroid?

  • Medical Reviewer: Mahammad Juber S, MD
Medically Reviewed on 6/2/2022

What is the thyroid?

Thyroid disease is a very common health problem. There is no specific diet that will dramatically affect the symptoms of thyroid disease.
Thyroid disease is a very common health problem. There is no specific diet that will dramatically affect the symptoms of thyroid disease.

Thyroid disease is a very common health problem. As many as 20 million people in America have some form of thyroid disease. It is especially common among women.

There are safe and effective medical treatments for thyroid conditions, and your doctor can help you get the right medicine for your condition. Additionally, eating a healthy, balanced diet can be part of your overall plan for good health after a thyroid disease diagnosis.

The thyroid is an organ that is part of the endocrine system. It's a small gland that sits in your throat and wraps around your windpipe. It produces hormones that control your metabolism.

Your metabolism is the system that converts food to energy that your body can use. Thyroid hormones make sure that your metabolism creates the right amount of energy for you to function normally. When it works properly, the thyroid produces and releases hormones at a steady rate.

What is thyroid disease?

If your thyroid doesn't produce the right amount of hormones, you may have a thyroid disease. If your thyroid over-produces hormones, that disease is called hyperthyroidism. When your thyroid doesn't produce enough hormones, it's known as hypothyroidism.


Symptoms of hypothyroidism include:

Various conditions can cause an under-active thyroid, including: 


Inflammation or swelling of the thyroid can reduce the production of thyroid hormones. This can occur due to illness such as the flu or a bacterial infection or else as a side effect of certain medications. You may experience painful swelling around the gland.

Hashimoto's thyroiditis

Hashimoto's disease is an autoimmune condition that occurs when your body attacks and damages your thyroid. It is an inherited condition. It is the most common form of hypothyroidism.

Postpartum thyroiditis

You may observe a decrease in thyroid hormones after giving birth. This condition is usually temporary. 

Iodine deficiency 

Your thyroid needs iodine to produce hormones. You usually get iodine through your diet. Consequently, if you don't consume enough iodine, it can affect your thyroid. This happens most commonly if you are taking a medication that inhibits iodine absorption.


Symptoms of hyperthyroidism include:

Various conditions will cause the thyroid to produce too much hormone, including:

Graves' disease

In cases of Graves' disease, your entire thyroid gland is overactive and produces too many hormones. This condition is also called diffuse toxic goiter.


One or more nodules within the thyroid can become overactive while the rest function normally. One overactive nodule is called a toxic, autonomously functioning thyroid nodule, while a gland with more than one overactive nodule is called a toxic multi-nodular goiter.


Inflammation of the thyroid can lead to overproduction of thyroid hormone. This can be caused by bacterial infections, illnesses such as the flu, or certain medications. You may notice swelling and pain in your throat. 

Excessive iodine

If you consume too much iodine, your thyroid will use it to produce more thyroid hormones than you need. This can happen if you are taking medicines that contain high amounts of iodine. 

What foods are bad for the thyroid?

There is no specific diet that will dramatically affect the symptoms of thyroid disease. Some experts suggest avoiding soy products such as tofu or soy milk if you are on medications to replace thyroid hormones in your body. Soy can interfere with how well your body absorbs the medication. Your doctor can tell you if you should limit or eliminate soy from your diet.

Unless otherwise directed by your doctor, you can eat foods that are naturally rich in iodine, even if your thyroid is hyperactive. Eating iodine-rich foods like fish and dark leafy greens is unlikely to affect how your thyroid functions.

Thyroid disease is a chronic illness that requires care and attention to your overall health, so most experts suggest eating a healthy, balanced diet to support good health. Choose a variety of fruits and vegetables, as well as foods with whole grains. Lean meats and fish are a good source of protein, as are nuts and legumes like beans. Your doctor may suggest that you increase the amount of fiber in your diet, particularly if you have digestive issues due to underactive thyroid.


Hyperthyroidism: Symptoms, Treatment, Medication See Slideshow

Can cutting out gluten help thyroid disease?

Hashimoto's disease is an autoimmune condition that causes an underactive thyroid. You may have digestive symptoms that accompany this condition. Certain foods can aggravate digestive symptoms, including foods high in gluten, sugar, or highly processed foods.

You may find that cutting back on these foods makes you feel better. You may not experience stomach discomfort as frequently. Removing gluten from your diet won't change how your thyroid functions, but you may find that it improves your quality of life.

What is a low-iodine diet for thyroid disease?

If you have a hyperactive thyroid, your doctor may prescribe radioactive iodine. This will damage some of the cells in your thyroid and lower the amount of hormone it produces. You may need to limit your iodine intake prior to starting the treatment, though, so that the medication is maximally effective. 

Foods that you may need to limit for a low-iodine diet include: 

  • Blackstrap molasses
  • Egg yolks, whole eggs, and foods containing whole eggs
  • Commercially prepared bakery products that contain iodate dough conditioners
  • FD&C red dye #3 
  • Foods that contain the additives carrageen, agar-agar, alginate, or nori
  • Iodized salt
  • Milk or other dairy products, including ice cream, cheese, yogurt, butter, and milk chocolate
  • Seafood, including fish, sushi, shellfish, kelp, or seaweed
  • Soy products, including soy sauce, soy milk, and tofu
  • Vitamins or supplements that contain iodine

If you have thyroid disease, talk to your doctor about what dietary changes might make you feel better. 

Medically Reviewed on 6/2/2022

American Thyroid Association: "General Information/Press Room." "Low Iodine Diet."

Endocrine Web: "Gluten and Autoimmune Thyroiditis." "Thyroid Gland: Overview."

Harvard Health Publishing: "Healthy Eating for a healthy thyroid."

National Health Service: "Thyroiditis."

National Institute of Diabetes and Kidney and Digestive Diseases: "Hyperthyroidism (Overactive Thyroid)." "Hypothyroidism (Underactive Thyroid)."