Iodine Intake Calculator: How Much Are You Actually Getting?
Iodine hides in some foods and is missing from most. Look anything up, then add your real day and see where your total falls:
Nothing added yet. Look up what you actually ate today and add each item.
Written and medically reviewed by Dr. Westin Childs, D.O. Last reviewed: August 28, 2026
How To Use This Calculator:
#1. Pick Your Thyroid Situation
The same iodine total reads differently with Hashimoto’s, hyperthyroidism, or a pregnancy, so the calculator asks first.
#2. Look Up Anything
Every food people ask about, from cod and milk to bananas and strawberries, plus the high-dose sources that actually cause problems: kelp supplements, iodine drops, and two medications.
#3. Add Your Real Day
Your salt habits and your thyroid medication go in first (yes, your medication: thyroid hormone is made of iodine and your body recycles it), then add what you ate and see if your total is in the physiologic range of 150 to 300 mcg I recommend.
Where Iodine Actually Hides (And Where It Does Not)
Iodine confuses thyroid patients more than any other nutrient, and the reason is that both directions are true: too little impairs thyroid hormone production, and too much can suppress your thyroid and aggravate Hashimoto’s.[1][2]
The real sources in an American diet are short: dairy, eggs, seafood, iodized salt, and bread made with iodate dough conditioners. That’s most of the list.[3] And then there are the sources you’re probably not counting: povidone-iodine antiseptics and gargles absorb through skin and mouth, red dye number 3 is about half iodine by weight, some cosmetics and personal care products carry iodine, and your thyroid medication itself is made of iodine that your body recycles. The calculator counts all of them.
And the salt you’re eating probably isn’t iodized. Sea salt, Himalayan salt, and kosher salt have essentially none, and the salt in processed and restaurant food isn’t iodized either. You can eat a very salty diet and still come up short.
Kelp is the opposite problem. A single kelp capsule can carry several times the daily upper limit, label accuracy is notoriously poor, and it’s the most common way thyroid patients accidentally megadose iodine while trying to help their thyroid. My position on dosing hasn’t changed: physiologic amounts of 150 to 300 mcg daily, and I’ve written about why high-dose iodine is a risk I don’t recommend taking.
Frequently Asked Questions
About 3 mcg per banana, so you’d need 50 bananas to hit the daily target. Strawberries are just as low at about 2 mcg per cup, which means fruit isn’t a real source of iodine.
Yes, but skip the megadoses. With Hashimoto’s, iodine deficiency and iodine excess BOTH work into the disease, and high intakes can aggravate the autoimmune attack. The goal is to meet the 150 mcg target from food and a modest supplement, and stay far away from kelp products and high-dose drops unless your doctor has a specific reason.
Yes: the T4 molecule contains four iodine atoms, and a 100 mcg dose carries about 65 mcg of iodine bound inside the hormone itself. You absorb most of the tablet but not all of it, so about 40 to 50 mcg of that iodine gets recycled into your iodine pool, and that counts toward your intake.
The official upper limit for adults is 1,100 mcg per day. An occasional day above it is fine, but sustained high intakes, almost always from kelp or high-dose supplements, can suppress thyroid function, trigger dysfunction in both directions, and aggravate autoimmunity. If your daily total is above the limit, the fix is nearly always removing one product.
Related Tools
- Thyroid Food Checker: the verdict on any food with your thyroid condition
- Medication Timing Optimizer: your supplements scheduled around your dose
- All Thyroid Calculators & Quizzes: the full set of free tools
Scientific References
- Zimmermann MB. Iodine deficiency. Endocr Rev. 2009;30(4):376-408.
- Leung AM, Braverman LE. Consequences of excess iodine. Nat Rev Endocrinol. 2014;10(3):136-142.
- Office of Dietary Supplements, National Institutes of Health. Iodine: Fact Sheet for Health Professionals. Updated 2024.
- Pearce EN, Pino S, He X, Bazrafshan HR, Lee SL, Braverman LE. Sources of dietary iodine: bread, cows milk, and infant formula in the Boston area. J Clin Endocrinol Metab. 2004;89(7):3421-3424.
