What Should You Eat If You Have Hyperthyroidism

Hyperthyroidism is when your thyroid produces too much thyroid hormone. This sends your entire body into overdrive, speeding up your metabolism and often causing weight loss.

The most common cause is an autoimmune disease called Graves' disease, but it can also temporarily be caused by a type of thyroiditis.

What are the symptoms of hyperthyroidism?

People's bodies respond differently to an imbalance of thyroid hormones. This results in a wide variety of symptoms, and not all patients will have all or even most of them.

Some common symptoms include:

• Unexplained weight loss

• Anxiety

• Irritability

• Mood swings

• Insomnia

• Fatigue

• Lack of tolerance to heat

• Irregular heart rate

• Twitching or trembling

• Goiter, which is when your thyroid gland swells up and creates a noticeable lump in your neck

• More frequent bowel movements

• Light and/or irregular menstrual periods

Causes and risk factors for hyperthyroidism

Hyperthyroidism has a variety of different causes and risk factors. Known risk factors include:

• A family history of hyperthyroidism

• Being female

There are several common causes of hyperthyroidism, some of which are temporary and easily treatable or may self-resolve. They are:

Graves' disease

This is an autoimmune disease that causes your thyroid gland to grow. Graves' disease is genetic and not curable but is treatable.

Toxic nodular goiter

This condition causes your thyroid to grow nodules or lumps that increase thyroid hormone production.

Iodine consumption

Consuming too much iodine, particularly kelp seaweed supplements, can lead to hyperthyroidism.

Medication dose

Taking the incorrect medication dosage for hypothyroidism (underactive thyroid gland) may lead to hyperthyroidism.

Thyroiditis

Thyroiditis is a generic term for inflammation of the thyroid. Thyroiditis sometimes causes an initial burst of overactivity followed by a longer period of underactivity before it resolves. 

Thyroiditis can be caused by autoimmune issues, infections, or pregnancy. Postpartum thyroiditis typically results in one to two months of hyperthyroidism followed by four to five months of hypothyroidism.

Can hyperthyroidism be treated with diet alone?

The short answer is generally not. If you have temporary (transient) hyperthyroidism caused by excessive iodine consumption or sensitivity to iodine, stopping the supplements and cutting your iodine consumption (such as using non-iodized salt) may resolve the problem.

However, in other cases, hyperthyroidism cannot be treated just with diet. For people with permanent hyperthyroidism, surgery or radioactive iodine treatment is used to intentionally damage the thyroid so that it stops overproducing thyroid hormone.

For temporary thyroiditis or people who are not candidates for surgery, medication may be used to normalize the thyroid. In many cases of thyroiditis, you then have to switch to the temporary use of thyroid hormone replacement medication.

However, this does not mean diet can't help with the symptoms of hyperthyroidism.

What is the best diet for hyperthyroidism?

No specific diet can treat hyperthyroidism, but some people have had success in supporting the thyroid and reducing inflammation with certain dietary alterations. Here are some recommendations to help improve symptoms:

Reduction of iodine

Reduce iodine intake unless you have been advised to take iodine supplements before surgery. Avoid kelp products altogether as they are very high in iodine.

Other foods high in iodine include fish, other types of seaweed, shrimp, dairy products, and grain; reduce your consumption of these foods. Use table salt that doesn’t contain added iodine.

Foods low in iodine include egg whites, unsalted nuts, nut butter, and moderate portions of meat.

Reduction of sodium

Many of us have too much sodium in our diets, potentially contributing to swelling, which can be a symptom of Graves' disease.

Eat more fruits and vegetables

Eat more cruciferous vegetables¹ such as broccoli, cauliflower, and cabbage. These contain goitrogens, which can interfere with thyroid hormone production and thus drop your levels.

However, if you have postpartum thyroiditis or similar, you should be careful as your thyroid will probably become underactive for a time, and, at that point, you should reduce the consumption of these foods.

Other types of fresh vegetables and fruits are also beneficial for giving you a good amount of antioxidants and improving your energy levels.

Increase selenium intake

Increase your selenium levels. Selenium² helps reduce symptoms of autoimmune thyroid disease.

Good sources of selenium are meat products, fish (but be aware of iodine levels), pasta, rice, bread, and cereals.

You can also talk to your doctor or nutritionist about whether you should take a selenium supplement.

Increase iron levels

Make sure you get enough iron³, as iron deficiency has been linked to hyperthyroidism. Consider foods such as raisins, white beans, black beans, dark chocolate, lentils, and chickpeas.

Increase calcium levels

Calcium matters, too, when it comes to hyperthyroidism. If your hyperthyroidism was not diagnosed quickly (and in many cases, it isn't), then you are at higher risk of osteoporosis⁴.

Make sure you get enough calcium and vitamin D to support bone health. In some cases, the bone-weakening can be reversed with proper treatment, but this is less likely to happen if you have had hyperthyroidism for a long time.

Add turmeric to your diet

Use turmeric in your diet. In addition to being delicious, turmeric contains an anti-inflammatory substance called curcumin⁵. Curcumin can help reduce thyroiditis (and is good for your joints).

You can also take a curcumin supplement, but check the ingredients; curcumin needs to be combined with other ingredients to work.

Decrease caffeine intake

Reduce the amount of caffeine you consume. If you are experiencing insomnia, anxiety, tremors, or an irregular heart rate, avoid caffeine since it can worsen these symptoms.

Another thing to consider is that Graves' disease and celiac disease are often comorbidities. There are some indications that even if you don't have clinical celiac disease, a gluten-free diet can offer some benefits.

If you are getting radioactive iodine treatment, you should avoid soy and soy products before and during the treatment.

If you have postpartum thyroiditis and are breastfeeding, you should talk to a nutritionist about your specific situation to ensure you and your baby get appropriate nutrients.

Again, there's no specific "hyperthyroid diet," but these are all things that are worth trying to see if they help your symptoms. If in doubt or overwhelmed, talk to a nutritionist who can advise you on the best course of action.

How else is hyperthyroidism treated?

There are three main options for treating hyperthyroidism:

Anti-thyroid medication

This is used for temporary hyperthyroidism or in people who are not good candidates for other treatment. There are two kinds of drugs, methimazole (MMI) and propylthiouracil (PTU).

MMI is preferred in most cases as it has fewer adverse effects and is only taken once a day. However, it is teratogenic (can cause developmental abnormalities) and can't be used during pregnancy or if you are trying to get pregnant.

Radioactive iodine therapy

Radioactive iodine can be administered orally. This is absorbed quickly by the thyroid, reducing thyroid hormone production.

Unfortunately, it is relatively common to experience long-term hypothyroidism after radioactive iodine therapy. However, this is generally considered preferable as the treatment for hypothyroidism – levothyroxine – has fewer side effects.

Surgery

Surgery can be undertaken to remove overactive nodules or part of the thyroid. This is typically done if the person is not a good candidate for iodine therapy. Many doctors consider surgery a last resort, especially as it can leave scarring on the neck.

It's worth noting that, in most cases, hyperthyroidism caused by thyroiditis will go away on its own. If you have thyroiditis, your levels will be monitored carefully, and you may have to switch from one set of thyroid medications to another as your thyroid recovers from the inflammation.

Postpartum thyroiditis is likely to return with subsequent pregnancies⁶. Because of this, your doctor might recommend thyroid monitoring during any subsequent pregnancy.

Other lifestyle measures for hyperthyroidism

Are there any other lifestyle changes you can make to reduce symptoms and help your thyroid? Yes. Maintaining a healthy weight can help. You may be underweight, and your nutritionist may recommend an increase in calories, or you may experience weight gain after going on medication.

You should exercise to the extent that you are able to. Hyperthyroidism can result in exercise intolerance, but ideally, you should be doing cardiovascular exercise and resistance training to help strengthen the bones.

Another big issue is the management of stress. Because hyperthyroidism causes anxiety and irritability, being stressed can result in an unpleasant feedback cycle that can affect your life and relationships. Consider relaxation techniques, yoga, regular exercise, and, if necessary, therapy.

The lowdown

There is no specific recommended diet for people with hyperthyroidism. However, there are some general guidelines that can help, such as reducing iodine and sodium and increasing selenium.

People with hyperthyroidism should also eat an overall healthy diet and try to maintain a good weight. While hyperthyroidism can cause weight loss (although not always), treatment can cause weight gain.

The most important advice is to eat lots of fruits and vegetables as part of a balanced diet.