The measured one
Potassium iodide
Gives a steady, measured amount. The form in most prenatals and multis.
Good for: Everyday use · Pregnancy planning
What variations of iodine exist?
A trace mineral the thyroid uses to make its hormones. Both too little and too much can cause thyroid problems, so more is not better. It comes in 4 forms, and they aren't all the same. Here's how they differ.
For education only. What's right for you depends on your health and your medications, so check with your provider before you start or switch. Book a consult
Our top pick
Every form, in plain words
The measured one
Potassium iodide
Gives a steady, measured amount. The form in most prenatals and multis.
Good for: Everyday use · Pregnancy planning
The other measured one
Sodium iodide
Also gives a steady, measured amount.
Usually skip
- The high-strength one (Molecular iodine or Lugol's-type mixtures)Usually very strong. Only with close guidance from your practitioner.
- The unpredictable one (Kelp or seaweed)Iodine amounts swing a lot from batch to batch, and seaweed can carry arsenic and other heavy metals.
Spotting a good one on the shelf
Look for
- Look for 'Potassium iodide' on the label (the measured one)
Watch out for
- Kelp, bladderwrack, or seaweed in a 'thyroid support' formula, where the iodine amount may be unpredictable
- High-dose iodine sold for thyroid or breast health
- Iodine adding up from a multi, a prenatal, a thyroid formula, and seaweed snacks
Check with your provider first if…
- Hashimoto's, Graves', or thyroid nodules. Extra iodine can trigger or worsen thyroid autoimmunity and can push thyroid levels too low or too high in susceptible people.
- Taking thyroid medicine, antithyroid medicine (such as methimazole), amiodarone, or lithium
- Pregnancy and breastfeeding. Iodine is important, but ask how much your prenatal should contain.
- Signs of too much: new thyroid symptoms, a metallic taste, acne-like rash, or swelling in the neck
In Dr. Lesher's store
2 products in Dr. Lesher's dispensary have iodine. Here's which form, where the label says.
Check with your provider before taking any of these, especially if you're pregnant or take medications.
MegaFood
Baby & Me 2™
75 mcg per serving
MegaFood
Baby & Me 2™ Postnatal Multi
145 mcg per serving
Ready to find the root cause?
Dr. Lesher is a Naturopathic Doctor who focuses on autoimmune and chronic conditions in women. Since 2020, she's helped hundreds of patients stop managing symptoms and start healing.