Low-Iodine, High-Protein Diet

Your doctor has prescribed you a low-iodine diet in preparation for tests or treatment for a thyroid condition, but you need a high-protein diet to exercise or just to feel healthy. This is a conundrum, because most high-protein foods are not low-iodine foods. Fortunately, plenty of foods are both. A diet of this type does not mean hours in specialty shops or in the kitchen, or depriving yourself of variety and flavor.


The most common reasons to be put on a low-iodine diet is that you are about to undergo either radioactive iodine treatment (RAI) or RAI scanning either to check for disease or monitor you after treatment. An RAI test is done to determine how much iodine your body uses, the Ohio State University Medical Center. Consuming too much iodine before the test would skew the results, and lowering the level of iodine in your body helps the treatment be more effective. A low-iodine diet means that you should consume no more than 50 micrograms of iodine per day, according to the doctors at California's Entrust Medical Group 2. This is less than 1/8 teaspoon of table salt, though that doesn’t mean you have to give up salt — just sea salt and iodized salt. A high-protein diet is generally a matter of personal taste, either to help build muscle or to lose weight, and the two diets are not mutually exclusive.


You don’t have to eat a lot of animal products to have a diet that’s high in protein. According to researchers at the Harvard School of Public Health, beans, nuts and whole grains are better protein choices than those in animal products, because they have so much less fat and cholesterol 3. The Thyroid Cancer Survivors’ Association recommends that you have no more than 6 ounces of meat per day 1. A 6-ounce porterhouse steak, for example, has 38 grams of protein and 44 total grams of fat, of which 16 grams are unhealthy saturated fat. One cup of cooked lentils, meanwhile, has 18 grams of protein, but only 1 gram of unsaturated fat. So, even though you’d have to eat three servings of lentils to match the protein in a steak, you’re still taking in much less saturated fat.

Foods to Enjoy

Unsalted, roasted nuts and seeds are an excellent low-iodine source of protein. Legumes are good, and beans except for cowpeas, lima beans, navy beans, pinto beans, red kidney beans and soy beans, the Thyroid Cancer Survivors’ Association cautions 1. Fresh fruits and vegetables are all allowed, and dark green vegetables like spinach and broccoli contain protein. Combining vegetables with grains and nuts is nutritious, lower in fat than animal products and flavorful. Most soft drinks, diet soft drinks, lemonade, coffee and tea, wine, beer and other alcohol are also allowed on a low-iodine diet, though you should consume any alcohol in moderation. Egg whites are high in protein and have no fat, cholesterol or iodine, so they are perfect for a low-iodine, high-protein diet.

Foods to Limit

Rice can be low-iodine depending on where it’s grown. Basmati rice is usually grown in places where the soil is low-iodine, but limit your intake to one serving – about ½ cup – per day, the Thyroid Cancer Survivors’ Association recommends 1. Cereals and grains that you buy raw and cook yourself are generally low in iodine, and you can have four servings per day. Have no more than 6 ounces of meat or poultry per day, but make sure it’s fresh and that you cook it at home. Stay away from processed meats like cold cuts, bacon and packaged, frozen meats that may be injected with iodized salt as a preservative. You don’t have to sacrifice protein on a low-iodine diet, but you do have to cut back on or avoid some animal products.

Foods to Avoid

Do not use iodized salt for seasoning. Foods high in iodine include seafood, shellfish and all sea-based products like sea salt, seaweed and kelp, the Thyroid Cancer Survivors’ Association explains 1. Certain preservatives are sea-based, so on a low-iodine diet it’s important to avoid processed foods completely, or to read the labels and stay away from algin, alginate, agar, carrageenan and nori. All dairy products like milk, cheese and ice cream contain higher levels of iodine than you want, and so do non-dairy creamers. Whole eggs, egg yolks and any pasta or baked goods that contain eggs contain iodine, and so do most boxed or packaged rices. Avoid cowpeas, lima beans, navy beans, pinto beans and red kidney beans, and all soy products except for soy oil and soy lecithin. Rhubarb also contains high levels of iodine. Many vitamins, supplements and medications contain iodine, so read the labels or consult your doctor.