How to Read a Food Label in 30 Seconds

The short version

Start with the serving size, as it may be smaller than what you eat.
Use the 5/20 rule. 5% Daily Value or less is low, and 20% or more is high.
Check for added sugar, sodium, fiber and protein.
Ingredients are listed by weight, and front-of-box claims are mostly marketing.

The four checks

1. Serving size

All the numbers on the label are per serving. A bag of chips might be "about 3 servings," so a 150-calorie label means 450 if you finish the bag. Many drinks and snack packs now list both a per-serving and per-package number.

2. Calories

These tell you how much energy you get from one serving. Compare to how filling it'll be. A 200-calorie bar and a 200-calorie meal of chicken and vegetables won't hold you the same way.

3. Percent Daily Value (the 5/20 rule)

5% or less of the Daily Value per serving is low.
20% or more is high.

So you can compare quickly without doing any math. Look for:

Want less	Want more
Added sugars	Fiber
Sodium	Protein
Saturated fat	Calcium, iron, potassium, vitamin D

4. Ingredient list

Ingredients are listed in order of weight, with the most first. It tells you whether "whole grain" bread is mainly whole wheat, or whether your granola's second ingredient is sugar. A short list of familiar things is usually a good sign.

Front-of-box claims, decoded

Claim	What it means in practice
Natural	Little legal meaning for most foods
Multigrain	Several grains, not necessarily whole
Made with whole grains	May contain only a small amount
Low-fat	May have added sugar or starch to make up for it
Sugar-free	May still be high in calories or sugar alcohols
Keto, paleo, plant-based	Says nothing about whether it's healthy
No added sugar	No sugar added, though it can still be high in natural sugar, like juice
Light	Lower in calories or fat than the original, which could've been very high
Protein	Check the grams. Some "protein" snacks have 5 g and plenty of sugar
Gluten-free	Important for celiac disease, but it isn't automatically healthier

A real comparison

Two breakfast cereals look similar on the front. Flip them over:

Per serving	Cereal A	Cereal B
Calories	160	150
Added sugar	12 g	1 g
Fiber	2 g	6 g
Protein	3 g	6 g
First ingredient	Sugar	Whole-grain oats

Cereal B wins, and it takes just a few seconds to see why.

Don't overdo it

Labels are a tool for comparing foods, not a test to pass. Foods without labels, such as fruit, vegetables, eggs and fresh fish, are often some of your best options. If reading labels has started making you feel anxious, see this guide.

Sources

This guide is general information, not medical advice. Please check with a clinician before making big changes, especially if you have a health condition, take medication, or are pregnant. Read the full disclaimer.