Hyperthyroidism occurs when there is too much thyroid hormone in your body. This condition is also called thyrotoxicosis. An overactive or enlarged thyroid gland may produce more thyroid hormone.
Your thyroid is a butterfly-shaped gland in the front of your neck. It produces thyroid hormones called T3 and T4.

Diet in hyperthyroidism

After treatment, dietary iodine balance is still important. Foods help protect your thyroid and reduce the long-term effects of hyperthyroidism.
Recommended foods in case of hyperthyroidism

1-  Low iodine foods

Mineral iodine plays a key role in the production of thyroid hormones. A low-iodine diet helps lower thyroid hormones. Add these foods to your daily diet:
 Salt without iodine
 Coffee or tea (without milk or dairy or soy-based creams)

• egg white

•  Fresh or canned fruit

•  Raw nuts and their butter

• Homemade bread or breads made without salt, dairy and eggs

• Popcorn with iodine-free salt

•  Oat

•  Potatoes

•  Honey

2.    Cruciferous vegetables
Cruciferous vegetables and other types may stop your thyroid from using iodine properly. They may be helpful for hyperthyroidism:

•  Bamboo branches

•  Buk Choi

•  Broccoli

•  Brussels sprouts

•  Cauliflower

•  Collard leaves

•  Kale

•  Yellow turnip

3.    Vitamins and minerals
Several nutrients are essential for thyroid health and the balance of thyroid hormone production.

Iron

Iron is important for many vital bodily functions, including thyroid health. Low iron levels are associated with hyperthyroidism. Get plenty of iron in your diet with foods like:

•  Dried beans

•  Green leafy vegetables

•  Lentils

•  Nuts

•  Poultry, such as chicken and turkey

•  Red Meat

•  Grains

•  Whole grains

    Selenium

Selenium-rich foods may help balance thyroid hormone levels and protect the thyroid against disease. Selenium helps prevent cell damage and keeps your thyroid and other tissues healthy.
Good food sources of selenium include:

• Chia seeds

•  Mushrooms

•  Tea

•  Meat such as beef and mutton

•  Rice

•  Oat bran

•  Poultry, such as chicken and turkey

•  Sunflower seeds

  Zinc

Zinc helps you use food for energy. This mineral also keeps your immune system and thyroid healthy. Food sources of zinc include the following:

•  Beef

•  Pea

•  cacao powder

•  Almonds

•  Mushrooms

•  Pumpkin seeds

•  Lamb

   Calcium and Vitamin D.

Hyperthyroidism causes weak and brittle bones. Bone mass may be repaired with treatment. Vitamin D and calcium are essential for building healthy bones.
4.    Healthy fats
Fats made from whole foods, mostly unprocessed, may help reduce inflammation. This helps protect thyroid health and the balance of thyroid hormones. Non-dairy fats are important in a low iodine diet. This includes:

•  Flax seed oil

•  olive oil

•  Avocado oil

•  coconut oil

•  Sunflower oil

•  Avocado

•  Raw nuts and seeds

    Foods that should be avoided if you have hyperthyroidism.
    Too much iodine
Eating too many iodine-rich foods can lead to hyperthyroidism or, in some cases, worsening of the thyroid.
Avoid the following seafood and seafood additives:

•  Fish

•  Seaweed

•  Shrimp

•  Crabs

•  Sea lobster

•  sushi

    Nitrate

A chemical called nitrate may cause your thyroid to absorb too much iodine. This can lead to an enlarged thyroid and hyperthyroidism.
Avoid foods such as the following:

• Processed meats

•  Celery

•  Lettuce

•  Beets

•  Spinach

•  ParsleyLeeks

    Gluten

In some people, gluten can damage the thyroid gland by causing inflammation. Even if you do not have allergies or gluten intolerance, limiting gluten is helpful. Check food labels for gluten-containing ingredients such as the following:

• Wheat

• Brewer's yeast

• Malta

• Rye