How to read a Nutrition Facts label

Eating with data · Published October 2, 2026

If you grew up in Mexico, Chile or Peru, you learned to read food by its black octagons. In the U.S. there are no octagons: everything is in the box on the back. Here's how to read it in under a minute.

In three steps: 1) check the serving size and how many servings are in the package, 2) look at the numbers you care about, 3) use the % Daily Value: 5% or less is low, 20% or more is high. That's the FDA's own rule of thumb.

1 · Serving size first

Every number on the label is per serving, not per package. A bag of chips might say "about 3 servings". If you eat the whole bag, multiply everything by three.

Serving sizes are based on how much people typically eat, not on how much they should eat.

2 · Calories

In large type, per serving. The label uses "calories"; in nutrition science and on many Latin American labels the same thing is written "kcal" (kilocalories). One calorie on a U.S. label equals one kcal.

3 · % Daily Value

The % DV tells you how much of a day's reference amount one serving covers, based on a 2,000-calorie diet. You don't need to do math:

5% DV or less is low.
20% DV or more is high.

Some reference values the label uses: sodium, less than 2,300 mg; dietary fiber, 28 g; added sugars, 50 g.

4 · Added sugars

"Total Sugars" includes the sugar naturally in milk or fruit. "Includes Added Sugars", just below, is the sugar put in during processing. That second line is the one closest to what a Mexican label measures for its "EXCESO AZÚCARES" warning.

5 · Sodium

The FDA says more than 70% of the sodium Americans eat comes from packaged and prepared foods, not the salt shaker. Bread, deli meats, cheese, soups and sauces add up. More in our Spanish guide «Sodio: de dónde viene el que comes».

6 · Rounding

Labels round. Under FDA rules, a serving with less than 0.5 g of trans fat can say 0 g, and one with fewer than 5 calories can say 0. "Zero" means "very little".

Octagons vs. Nutrition Facts

	Black octagons (Mexico, Chile, Peru, Colombia, Argentina, Uruguay)	Nutrition Facts (U.S.)
Where	Front of the package	Back or side panel
Based on	Per 100 g or 100 ml	Per serving
What it tells you	Whether the product passes a legal limit	How much of each nutrient, and what share of a daily reference

Neither one says whether a food is "good" or "bad". The octagon is a warning; the % DV is a scale. To compare two products, use the same base for both: per 100 g is the fairest.

Compare with whole foods

On Micela, every food and dish is shown per 100 g and per typical serving, with its USDA source: see the calorie tables, and the rankings for sodium, fiber and sugar.

Frequently asked questions

How do you read a Nutrition Facts label?

Start with the serving size and servings per container, then look at calories and the nutrients you care about. Use the % Daily Value: 5% or less is low, 20% or more is high.

What does % Daily Value mean?

It's the share of a daily reference amount that one serving provides, based on a 2,000-calorie diet. For example, the reference for sodium is less than 2,300 mg.

What's the difference between total sugars and added sugars?

Total sugars include the sugar naturally in foods like milk and fruit. Added sugars are the ones put in during processing, and they're listed on their own line.

Does 0 g on a label mean there's none?

Not always. FDA rounding rules allow 0 g of trans fat if a serving has less than 0.5 g, and 0 calories if it has fewer than 5.

Sources

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Micela shows general information. It is not medical or nutritional advice.