How to Read a Supplement Facts Panel: A Walkthrough

Supplement Facts panels follow a standardized format. We walk through each section — serving size, amount per serving, % daily value — using a liquid iodine label as the example.

Why the Panel Looks the Same Everywhere

In the U.S., dietary supplements must carry a Supplement Facts panel in a format set by the FDA. Because every brand follows the same layout, once you know how to read one panel you can read them all, and you can compare products side by side.

1. Serving Size

The first line tells you what one serving is. For a tablet it might be "1 tablet"; for a liquid iodine it's usually a number of drops or a fraction of a milliliter. Everything else on the panel is calculated per serving, so this line is the key to everything below it.

2. Servings Per Container

This tells you how many servings are in the bottle at the listed serving size. It's useful for working out cost per serving and how long a bottle will last. See 2oz vs. 4oz Bottles: A Value Breakdown.

3. Amount Per Serving

This column lists each dietary ingredient and how much of it is in one serving. For iodine, the amount is usually given in micrograms (mcg) or milligrams (mg). Watch the units: 1 mg equals 1,000 mcg, and that difference matters a lot with iodine.

4. % Daily Value

The % Daily Value (%DV) shows how one serving compares with a reference amount for daily intake. The Daily Value for iodine on U.S. labels is 150 mcg for adults, matching the adult RDA. A product providing 150 mcg per serving would show 100% DV. Products that provide more than the Daily Value will show a percentage above 100%, which is common for concentrated liquid iodine.

5. Other Ingredients

Below the main panel, "Other ingredients" lists everything else in the product that isn't a dietary ingredient, such as the base liquid. This is where you'll see whether a product is water-based or glycerin-based, for example.

6. The Rest of the Label

• Directions: how the manufacturer suggests using the product.
• Warnings: who should talk to a doctor first, such as people who are pregnant, nursing or taking thyroid medication.
• FDA disclaimer: required whenever a label describes how a nutrient supports the body.
• Manufacturer information: who makes or distributes the product and how to contact them.
• Lot number and date: used to trace a batch and its test results.

Putting It Together

To compare two iodine products, line up their amount of iodine per serving, their serving sizes and their cost per serving. The percentage on the front of the bottle tells you concentration; the Supplement Facts panel tells you what you actually get. See Reading Your Bottle's Percentage Label. To check that a product matches its label, look for a Certificate of Analysis.

Frequently Asked Questions

Why do some iodine labels show more than 100% Daily Value?
Concentrated liquid iodine products often provide more than the Daily Value per serving. That's why it's important to follow the label and talk to a healthcare provider about the right amount for you.

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.

How does this panel translate into an actual daily dose?
See How to Take Lugol's Solution: Dosing, Dilution, and Timing for the practical walkthrough.

Shop Lugol's Solution — the traditional, trusted way people have supported their iodine intake for over 200 years.

Mark Donovan writes about the practical, self-reliant side of iodine sourcing and storage 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.