Some foods that contain iodine that you'll probably want to avoid are
Iodized salt, sea salt and salty foods. ...
All dairy products (milk, sour cream, cheese, cream, yoghurt, butter, ice cream)
Margarine.
Egg yolks.FOODS THAT ARE OK
Non-iodized salt may be used as desired
Egg whites
Homemade bread made with non-iodized salt and oil (not soy!) instead of butter or milk or commercially-baked breads which do not contain iodate dough conditioners, dairy, or eggs
Fresh fruits and vegetables
Frozen vegetables
Grain, cereal products and pasta without high iodine ingredients
Canned fruit
Natural unsalted nuts and nut butters (peanut, almond, etc)
Sodas, beer, wine, lemonade, fruit juices
Coffee or tea. But remember, no milk or cream and no soy-based non-dairy creamer!
Popcorn popped in vegetable oil or air popped, with non-iodized salt
Black pepper, fresh or dried herbs and spices, all vegetable oils
Sugar, jam, jelly, honey maple syrup
Matzoh crackers
ADDITIONAL GUIDELINES
Avoid restaurant foods since there is no reasonable way to determine which restaurants use iodized salt.
Consult your doctor before discontinuing any red-colored medication or any medication containing iodine (i.e., Amiodarone, expectorants, topical antiseptics).
Avoid all herbal supplements (especially when one is not sure how much iodine they contain
Seafood (fish, shellfish, seaweed, kelp)