What to Eat When You Have Hyperthyroidism

Dietary Recommendations for Better Management

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There’s no specific “diet” for people with hyperthyroidism, but adhering to certain dietary principles can support your thyroid medication and treatment plan’s effectiveness.

Depending on whether you have borderline numbers or a full-blown diagnosis, your doctor may suggest tweaking your food intake to slow the progression of hyperthyroidism.

Learning to balance your iodine intake, along with other ingredients that affect thyroid function (like soy, selenium, and cruciferous vegetables), can help keep your condition under control and avoid potentially harmful medication interactions.

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Benefits

Radioactive iodine therapy is often a procedure recommended to treat hyperthyroidism. People may be advised to be on a low-iodine diet before this treatment. After treatment for an overactive thyroid, most people end up with the opposite condition, an underactive thyroid or hypothyroidism.

To make up for the lack of thyroid hormone, you’ll be placed on synthetic thyroid hormone medication, called levothyroxine (brand names include Synthroid). Regular blood tests will indicate if your levels are within an ideal range or if your medication dosage needs adjusting.

With regular monitoring and small changes as needed, it’s usually possible to find the right balance of thyroid medication for your body. Maintaining a consistent dietary pattern that minimizes certain foods and ingredients leads to more predictable thyroid function.

Taking your thyroid into account when deciding what to eat and how to cook will let you avoid the ups and downs of too much or too little thyroid hormone (including weight fluctuations, feeling hot or cold, sleep disturbances, and more serious complications to the heart and bones).

How It Works

There’s no need to follow a particular eating schedule for hyperthyroidism. Instead, making a habit of checking food labels and selecting appropriate substitutions is sufficient to see a benefit.

Talk to your doctor about whether you should be on a low-iodine diet or you are at risk of becoming iodine deficient instead.

Duration

Rather than viewing these recommendations as a short-term diet, consider them to be general guidelines that are meant to be followed for life. As with any healthy eating plan, veering off track on occasion isn’t likely to cause significant harm. You’ll probably notice that you feel better when your thyroid levels are within the normal range.

What to Eat

Low Iodine
  • Home cooking

  • Non-iodized salt or sea salt

  • Chicken/beef/pork

  • Egg whites

  • Dry beans or canned with no added salt

  • Root vegetables

  • Any fruit (fresh, dried, frozen)

  • Unsalted nuts and nut butters

  • Most vegetables

High Iodine
  • Restaurant meals

  • Iodized salt

  • Seafood, shellfish, kelp, seaweed, dulse

  • Egg yolks

Salt: If your doctor recommends a low-iodine diet, avoid iodized salt and choose sea salt or non-iodized salt.

Seafood and seaweed: These items are naturally rich in iodine. Avoid these if a low-iodine diet is recommended by your doctor.

Eggs: Egg yolks are higher in iodine than egg whites. Choosing just the whites will help you keep your total iodine intake down if recommended.

Soy: Soy reduces the absorption of thyroid hormone from medication and should not be consumed in large quantities if you take thyroid medication or have an underactive thyroid.

Allergenic foods: Food allergies can worsen the symptoms of hyperthyroidism. Your doctor may want to test you for common allergens like dairy, gluten (from wheat), corn, food additives, and preservatives to make sure allergies aren’t contributing to your condition.

Brazil nuts: Brazil nuts are extremely high in selenium. Although selenium supports thyroid function, too much can cause problems for people on thyroid medications. If you have hyperthyroidism, it’s best to avoid getting more than 200 micrograms of selenium per day. This amount is easily found in less than 0.5 ounces of Brazil nuts.

Root vegetables: There is a common misconception that root vegetables can cause thyroid issues. However, experts agree that there is no reason to avoid root vegetables if you have hyperthyroidism.

Cruciferous vegetables: Kale, cauliflower, bok choy, broccoli, and Brussels sprouts are cruciferous vegetables from the Brassicaceae family. When consumed raw and in high volume, goitrogenic compounds in these vegetables may interfere with thyroid function. Cooking cruciferous vegetables and consuming them in moderation helps avoid potential problems with hyperthyroidism.

Recommended Timing

The only timing you need to worry about is when to take your medication. Thyroid medicine should always be taken on an empty stomach with water. Aim to take it at the same time every day, and wait at least 30 minutes before consuming any other food or beverages.

To avoid potential interactions, wait four hours after taking your medication to use antacids, calcium supplements, iron supplements, or multivitamins with calcium or iron.

Thyroid levels that are too high or too low can affect your energy level. Paying attention to the meal timing that works best to deliver consistent energy throughout your day is worthwhile.

For some people, eating less often helps prevent energy slumps. For others, small frequent meals work better. Keeping a food diary and noting how you feel can help you identify the proper eating schedule.

Cooking Tips

Cooking from home instead of eating at restaurants makes it easier to know what’s in your food. Processed foods are more likely to contain high levels of soy ingredients and salt (usually non-iodized). Choosing foods with a shorter ingredients list helps avoid preservatives and additives that may be troublesome with hyperthyroidism.

Modifications

If you have other autoimmune disorders that may accompany hyperthyroidism, such as type 1 diabetes or rheumatoid arthritis, you may need to take additional dietary precautions.

Considerations

Certain foods impair the effectiveness of thyroid medication, including:

  • Cottonseed meal
  • Dietary fiber
  • Grapefruit juice
  • Soy
  • Walnuts

It’s OK to continue eating these foods, but you should try to maintain some consistency with your intake so your medication can be adjusted to the proper dosage.

Individuals with pernicious anemia (vitamin B12 deficiency) are more prone to hyperthyroidism. If you have thyroid issues, it’s crucial to keep up with lab work and identify nutrient deficiencies that may be contributing to your condition.

Ask your doctor before starting any supplements (including multivitamins and herbal supplements), especially if you have borderline thyroid issues or take thyroid medication.

A Word From Verywell

While you should be mindful of how different foods and supplements can impact your thyroid, food shouldn’t cause stress. As long as your habits are relatively consistent and you keep up with your regular doctor’s visits, your medication can be adjusted to get your thyroid levels into a healthy range.

It’s normal to experience fluctuations, especially as you first begin getting a handle on a new diagnosis. Using your healthcare provider’s support, it’s possible to settle into a healthy balance with hyperthyroidism.

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Article Sources
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