A Certificate of Analysis verifies a product batch's tested composition. This post explains what a COA typically includes and how to read one.

Iodine supplementation raises a lot of practical questions, and clear, sourced answers are hard to find. This is exactly the kind of practical, side-by-side question I get asked most often, so let's break it down properly.

The Short Answer

A Certificate of Analysis typically lists the tested concentration, purity, and any contaminant screening results for a specific batch.

The Longer Explanation

COAs are usually tied to a batch or lot number, which should correspond to the number printed on the product packaging.

Requesting or reviewing a COA before purchase is a reasonable way for a buyer to verify a manufacturer's testing claims.

How to Think About This Day to Day

At the end of the day, an informed choice beats a marketing claim every time — that's the standard I try to hold every product, including our own, to.

Frequently Asked Questions

Should I talk to a doctor before starting?
Yes. Anyone considering a new supplement — especially one involving iodine — should check in with a healthcare provider first, particularly if pregnant, nursing, or managing a thyroid condition or thyroid medication.

Lauren Mitchell covers comparisons, formats, and quality questions for the Iodine Journal.

This article is for general educational purposes only and has not been evaluated by the FDA. It is not intended to diagnose, treat, cure, or prevent any disease, and is not a substitute for advice from a qualified healthcare provider — especially if you are pregnant, nursing, taking thyroid medication, or managing a thyroid condition.