The breakfast aisle is noisy with health claims. Remember "5-5-10" when reading box labels.
5 Grams of Fiber
There's no better time to get ahead on your daily fiber goal of 25 to 38 grams than at breakfast. It's your number one satiety factor. Five grams is the baseline; more is better. Whole grains are the best source—they should always be the first item on the ingredient list.
5 Grams of Protein
Choose cereals full of naturally occurring protein—like whole grains, nuts, and seeds—instead of ones that contain added proteins or "isolates," which are often highly processed. A half cup of skim milk adds 4 more grams of protein.
10 Grams of Sugar
That's the max you want in a serving: equal to 2 heaping teaspoons. Some complicated "healthy" cereals contain as much as 16g per serving—more sugar than a glazed doughnut. Added sugars should be low on the ingredient list, never first. Lots of dried fruit can also add lots of sugar. A lightly sugared whole-grain cereal can be a good choice if you tend to add too much sugar at home.