LowIodine Diet: Preparing to receive radioactive iodine
Why do I need to follow a lowiodine How will I know which foods are high
diet? in iodine so that I can avoid them?
Before you receive radioactive iodine (tracer or Because the iodine content of food is not listed
therapy dose), you must follow a lowiodine diet on food labels, nutrient counter books, or web
for about 2 weeks to prepare. sites, you cannot track how much iodine you
By limiting iodine in your diet, you deplete your consume.
body’s iodine supply. This makes your thyroid The foods highest in iodine are dairy (milk and
gland ”hungry” for iodine so that it will absorb milkbased products), egg yolks, fish, shellfish,
more radioactive iodine. Increased uptake of seaweed, chocolate, and a few specific grains.
radioactive iodine will make your treatment Beyond these foods, most iodine in the
more effective or your scan more accurate. American diet comes from iodized salt used at
What is iodine? the table and from a few food additives. The
Iodine is an essential mineral your body uses document, LowIodine Diet Food List, will
to make thyroid hormones. help you choose wisely.
This list will tell you:
How much iodine can I consume on
o What foods to avoid
the lowiodine diet?
On the lowiodine diet, your intake must be less
o What foods you can consume, but in limited
than 50 micrograms of iodine per day. You do amounts
this by limiting high iodine foods. o What foods you can eat in unlimited amounts
How much iodine do Americans Reading Ingredient Labels for Iodine
The Recommended Daily Allowance (or RDA, Notallowed Ingredients
the amount of iodine necessary for most These ingredients are not allowed in any
adults), is 150 micrograms per day. The usual amount. Check ingredient labels.
intake in the United States is about 150550 o Bread conditioners: “Calcium iodate” or
micrograms. By comparison, the lowiodine diet “potassium iodate”
is much lower in iodine than a person’s aver Avoid commercial breads and baked goods
age intake. unless you can verify the type of bread
You must follow this diet for only a short time: conditioner used.
2 weeks before treatment or testing with Note: Homemade bread/baked goods are
radioactive iodine. allowed.
o Sea salt
Patient Education 1 LowIodine Diet: Preparing to receive
o Red Dye #3 (E127 in Europe), also More about eating lowiodine
called eryrythrosine Processed foods
This is rare now, but check labels on Many canned, packaged, or frozen foods
foods dyed red or orange. contain added salt, and the label rarely
o Alginate, algin, agaragar, says whether salt in a food is iodized or
carrageenan, nori, algae, alginates, not. At the time of this publication, most
kelp, seaweed large manufacturers use noniodized salt
(See the list in this document, Food
These are seaweed or seaweedderiv
brands using noniodized salt, for spe
atives and should be avoided. Alginates
cific brand names.) Always check for not
thicken jellies, soup, ice cream, salad
dressings, and toothpaste. Sushi con
tains seaweed. o Small manufacturers may use iodized
o Egg yolk (the yolk contains the salt or sea salt, so you should try to
iodine) avoid those products during the short
time you follow this diet.
Limited Ingredients o Noniodized table salt is okay to use
The following foods are very high in while on a lowiodine diet.
iodine and are not allowed as whole
foods. But because it may be difficult for Restaurant foods
you to find products without these ingre Eating out on the lowiodine diet poses
dients, they are allowed as ingredients in two challenges.
small amounts. First, you will usually not know what type
o Cream or milk of salt restaurants use, and most prepare
o Chocolate foods with lots of added salt.
o Whole egg Second, restaurants often make their own
o Cheese marinades, spice mixes, dressings, and
sauces with iodized salt.
How small is a small amount?
There is not an easy answer to this ques So, if you eat out in a restaurant,
tion. Less is better since you must limit follow these tips:
your iodine intake. Think in terms of tea o Choose plainly prepared foods that are
spoons not measuring cups. allowed on your lowiodine diet.
Also know that ingredients are listed on o Make special requests that food be
the label from largest to smallest prepared without added salt, mari
amounts by weight. This means that if nades, or sauces.
one of these appears at the end of a long
o Use simple oil and vinegar instead of
list of ingredients, it most likely is present
dressing on a salad, or bring your own.
in only small amounts.
Patient Education 2 LowIodine Diet: Preparing to receive
o Spices and herbs without salt are Medications
allowed to flavor food. Some medications contain iodine (most
notably levothyroxine and triiodothyroi
o Home preparation: Similar to eating in nine). Check with your doctor to learn
restaurants. whether any of your medicines contain
iodine or should be stopped. Do not stop
Other iodinecontaining products any medication without speaking with
to avoid your doctor first.
Red Dye: Red Dye #3 (E127 in Europe), Some people use Betadine or other
erythrosine iodinecontaining products on their skin
Red Dye # 40 is okay. With this in mind, as an antiseptic. Avoid using this product
check about any pills or capsules while on the lowiodine diet. Instead
artificially dyed red, orange, or brown. choose hydrogen peroxide for cleansing
and an antibiotic cream if necessary.
o Calcium supplements made from Avoid creams or lotions made from
oyster shells may be high in iodine seaweeds (including kelp and spirulina)
and should be avoided. while on the lowiodine diet.
o Fish oil is also likely to be high in iodine Water purification
and should be avoided. (Omacor brand Avoid using iodine tablets while on this
is one exception and is allowed.) diet.
o Multivitamins also may contain iodine
and should be stopped while following
the lowiodine diet.
o Selenium supplements should also be
Some toothpastes contain alginates.
Check the label to find an acceptable
product for brushing your teeth.
Patient Education 3 LowIodine Diet: Preparing to receive
Food brands using ReddiWhip
noniodized salt Slim Jim
The following manufacturers report using
noniodized salt in their food production Kraft Brands
(as of this publication). You may safely use http://www.kraft.com/Brands/
foods prepared by these manufacturers A1
if they are on the “allowed” food list. Alpen Gold
Each manufacturer typically produces many Breakstone’s
brands, and many appear below. If you CapriSun
want a more comprehensive list, you can CarteNoir
always check the company’s website. CheezWhiz
Campbell Soup Brands Chips Ahoy
http://www.campbellsoupcompany.com/our_ Club Social
brands.asp Cool Whip
Campbell Soup Cote D’Or
Campbell California Pizza Kitchen
Pepperidge Farm Cracker Barrel
V8 Crystal Light
Pace sauces Deluxe
Swanson broths Estrella
General Foods International
http://www.conagrafoods.com/ Grand Mere
Chef Boyardee Handisnacks
David Seeds Honey Maid
Egg Beaters Jack’s
Healthy Choice Jacobs
Hebrew National JellO
Kid Cuisine KoolAid
Marie Callender’s Kraft
Orville Redenbacher’s Marabou
Patient Education 4 LowIodine Diet: Preparing to receive
Maxwell House General Mills
Miracle Whip Betty Crocker
Nilla Cascadian Farm
Nutter Butter Cheerios
Oreo Forno de Minas
Oscar Mayer Frescarini
Philadelphia (cream cheese) Fruit by the Foot
Planters Fruit Gushers
PollyO Fruit RollUps
Post Fruit Shapes
Prince Gold Medal
Ritz Green Giant
South Beach Muir Glen
Stove Top Nature Valley
Tassimo Pop Secret
Wheat Thins 8th Continent (soy)
Patient Education 5 LowIodine Diet: Preparing to receive
Bagel Bites Bakenets
Boston Market Chester’s
Delimax Cracker Jack
Jack Daniel’s Sauces El Isleno
Mr. Yoshida’s Sauces Flat Earth
Smart Ones Gamesa Cookies
T.G.I. Friday’s Grandma’s Cookies
Weight Watchers Lay’s
Wyler’s Maui Style Potato Chips
http://www.hormelfoods.com/brands/default.aspx Quacker Snack mix
ChiChis Rold Gold
Dinty Moore Ruffles
Farmer John Sabritones
Lloyds Stacy’s brand
Stagg Chili Sun Chips
World Food Tostitos
Patient Education 6 LowIodine Diet: Preparing to receive
Aunt Jemima Bertolli
Cap’n Crunch Blue Band
Kretschmer Wheat Germ Country Crock
Mother’s Natural Foods Hellman’s
Near East Knorr
Pasta Roni WishBone
PepsiCo What if the brand of the food I
(also owns Frito Lay and Quaker, previous want to eat is not on this list?
ly listed): http://www.pepsico.com/ This list does not name all food companies
Gatorade or their brands. By including a company on
Propel this list, NIH is in no way endorsing them.
Pepsi If you know of a brand not listed here, use
Tropicana your best judgment to decide whether to
include the food.
The guideline is that foods by large
manufacturers/ companies are generally
prepared with noniodized salt. Foods
prepared by smaller companies have a
greater risk for containing iodized salt and
being high in iodine.
Patient Education 7 LowIodine Diet: Preparing to receive
Is this information uptodate?
This information is based on written inquiry
in January 2009. While manufacturing
practices may change, we suggest that this
information is reliable. Please check the
NIH Clinical Center website for the most
uptodate information. We will make every
attempt to confirm the use of noniodized
salt by these manufacturers once a year.
We can also provide references if you ask
This information is prepared specifically for persons
taking part in clinical research at the National
Institutes of Health Clinical Center and may not apply
to patients elsewhere. If you have questions about
the information presented here, talk to a member of
your health care team.
Products/resources named serve as examples and
do not imply endorsement by NIH. The fact that a
certain product/resource is not named does not imply
that such product/resource is unsatisfactory.
NIH is not responsible for the content at provided
Internet site links; nor does NIH endorse, warrant,
or guarantee the products or services described or
offered at these Internet sites.
National Institutes of Health Clinical Center
Bethesda, MD 20892
Questions about the Clinical Center?
NIH...Turning Discovery Into Health
Patient Education 8 LowIodine Diet: Preparing to receive