This information describes dietary (eating and drinking) guidelines to help you follow a low-iodine diet. It also includes a sample low-iodine menu and answers some commonly asked questions about a low-iodine diet. A low-iodine diet is a diet with less than 50 micrograms (mcg) of iodine per day.
About Iodine
Iodine (I-oh-dine) is a mineral. Minerals are a type of nutrient your body needs to work properly. Your body uses iodine to make certain hormones (such as the hormones made by your thyroid gland) that help regulate other parts of your body.
All of the iodine in your body comes from your diet. Most of the iodine in your diet comes from iodized salt and other products made with added iodine. Only a few foods (such as seaweed, dairy, and some fish) naturally have iodine in them.
About a Low-Iodine Diet
Following a low-iodine diet before getting radioactive iodine therapy can help the therapy work best. If you have too much iodine in your body during your radioactive iodine therapy, your thyroid gland might use that iodine instead of the radioactive iodine. This keeps the treatment from working as well as it should.
Your healthcare provider will tell you when to start and stop following a low-iodine diet. Most people start 1 to 2 weeks before their dose of radioactive iodine and stop after their radioactive iodine therapy is finished.
Because a low-iodine diet doesn’t meet the suggested daily allowance for all nutrients, you’ll only follow it for a short time. Don’t start following a low-iodine diet unless your healthcare provider tells you to.
Foods, Drinks, and Other Items Containing Iodine
Before you eat or drink something, read the ingredient list on the Nutrition Facts label to check if the food or drink contains added iodine.
The following things contain added or natural iodine. Don’t eat or use:
- Iodized salt (such as Morton® Iodized Salt or any commercial salt that has “iodized” on the product label)
- Seasoning mixes made with iodized salt (such as adobo)
- Onion salt, celery salt, garlic salt, or seasoned salt made with iodized salt
- Seaweed (such as kelp, nori, kombu, and wakame)
- Any food that has these listed in its ingredients:
- Iodates
- Iodides
- Algin
- Alginates
- Carrageenan
- Agar-Agar
- Commercial (store-bought) breads and bakery products made with iodate bread conditioners. Read the ingredient list on the Nutrition Facts label to check if the product contains “calcium iodate” or “potassium iodate.”
- Milk (except for 1 ounce per day) and dairy products (such as cheese, yogurt, and cream)
- Egg yolks (the yellow part at the center of an egg)
- Most seafood (except freshwater fish)
- Vitamins and dietary supplements that have iodine. If you aren’t sure if a vitamin or supplement contains iodine, don’t take it.
- Food, pills, or capsules with food dyes that contain Red Dye #3
- Restaurant and processed foods (such as fast food, frozen meals and TV dinners, and sugar-sweetened drinks)
- Soy products, such as edamame, tofu, and soy burgers (BOCA® burgers)
- Antiseptics (liquid used to kill germs and bacteria), such as iodine (Betadine®) that you put on minor cuts, scrapes, and burns
- Medications that have Red Dye #3 listed in its ingredients
- Liquid nutritional supplements and commercial (store-bought) protein shakes, such as:
- Ensure®
- Boost®
- Glucerna®
- Nutrament®
- Orgain®
If you’re getting tube feeding formula, ask your clinical dietitian nutritionist or healthcare provider what to do.
Low-Iodine Diet Guidelines
The following tables include examples of low-iodine foods. If you have questions about foods not listed in these tables, call your clinical dietitian nutritionist or 212-639-7312 to talk with an outpatient clinical dietitian nutritionist. You can reach a staff member Monday through Friday, from to
Each food section below lists serving sizes that can help you follow a healthy, well-balanced diet. Serving sizes are suggestions for how much food and drink to have per day. You don’t need to follow these suggestions unless your healthcare provider tells you to. Serving sizes don’t give you the iodine content (how much iodine is in a certain food or drink).
Breads, cereals, and grains
Eat 4 to 6 servings of breads, cereals, and grains every day. One slice of bread or ½ cup of cooked pasta or grains is 1 serving.
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Meat, meat substitutes, and proteins
Eat 2 to 3 servings of meat, meat substitutes, and proteins every day. Three ounces of meat or poultry is 1 serving.
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Drinks
Drink at least 8 to 10 (8-ounce) glasses (about 2 liters) of liquids every day, unless your healthcare provider gives you other instructions.
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Milk and dairy products
Avoid milk and dairy products. It’s okay to have 1 ounce of milk per day (such as in your coffee or tea).
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Fruits
Eat as many servings of fruit per day as you want. One small piece of fruit or ¾ cup of fruit juice is 1 serving.
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Vegetables
Eat as many servings of vegetables per day as you want. One cup of raw vegetables or ½ cup of cooked vegetables is 1 serving.
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Fats
Eat 4 to 6 servings of fats every day. One teaspoon of butter or oil is 1 serving.
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Desserts and sweets
Limit to 2 servings per day. Each item in the “include” column is 1 serving.
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Condiments
Eat as many servings of condiments per day as you want.
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Miscellaneous
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Sample Low-Iodine Menu
| Meal | Food Groups | Example Meal |
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| Breakfast |
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| Morning snack |
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| Lunch |
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| Afternoon snack |
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| Dinner |
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| Evening snack |
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Frequently Asked Questions
How do I know if a certain food has iodine?
The iodine content of many foods isn’t known. Remember, this is a low-iodine diet, not a non-iodine diet. We encourage you to follow our list of recommended foods to include and foods to avoid as a guide. If you have questions, call your clinical dietitian nutritionist or 212-639-7312 to talk with an outpatient clinical dietitian nutritionist. You can reach a staff member Monday through Friday, from to
If a product label says it has sodium (salt), does that mean it also has iodine?
Not always. Sodium and iodine aren’t the same thing. Most commercial food manufacturers use non-iodized salt in their products. But, it’s hard to know for sure. It’s best to choose unsalted products in case a salted product contains iodine.
I saw dietary guidelines for a low-iodine diet on the Internet that are different than the guidelines in this resource. Which one should I follow?
We encourage you to follow our list of recommended foods to include and foods to avoid. This is because the iodine content of many foods isn’t known and not all Internet sources are correct.
Can I use kosher salt?
Yes. We recommend using only non-iodized salt and only in small amounts because it may still contain a small amount of iodine. If you need salt, choose kosher salt or Morton® Plain Table Salt and use only small amounts.
My healthcare provider told me to suck on hard candy for dry mouth, but this diet says I can’t have candy. Which instructions should I follow?
We recommend that you don’t eat any candy that has chocolate in it, because chocolate contains milk. But most hard candies are okay to eat if they don’t contain Red Dye #3. Read the ingredient list on the Nutrition Facts label of the candy to check if it contains Red Dye #3. If you aren’t sure if the candy contains Red Dye #3, don’t eat it. We also recommend GoNaturally™ Organic Honey Lemon hard candies for dry mouth.
Should I stop taking any of my medications?
Don’t stop taking any of your medications unless your healthcare provider tells you to. Talk with your healthcare provider if you have any questions about your medications.
Tell your healthcare provider about any vitamins or supplements you’re taking. You’ll need to stop taking them if they contain iodine.
Vitamins and supplements aren’t regulated (checked for safety, content, or quality) the same way other medications are. This makes it hard to tell if they contain iodine. If you aren’t sure if a vitamin or supplement contains iodine, don’t take it.
Can I drink alcohol?
Ask your healthcare provider about drinking alcohol.
Contact Information
If you want to speak with one of Memorial Sloan Kettering’s (MSK’s) clinical dietitian nutritionists, call 212-639-7312 to make an appointment. You can reach a staff member Monday through Friday, from to