Cereal, that old familiar breakfast staple, is less popular than it once was.

That’s in part because many consumers consider it to be low in protein, high in sugar, and too processed to be healthful, according to the market research firm Mintel. Although that’s true of many cereals, plenty are nutritious.

Plus cereal is quick and convenient, and can be an efficient way to get many essential nutrients all at once, says Ronni Chernoff, Ph.D., director of the Arkansas Geriatric Education Collaborative.

For breakfast she recommends covering four bases: fruit, protein, a complex carbohydrate, and dairy. Have a whole-grain cereal with milk topped with fruit to hit all four. What follows is everything you need to know to choose a healthy cereal.

Pick a Whole Grain

Look for a “100 percent whole-grain” claim on the box, or read the ingredients list to be sure all grains are whole, such as whole wheat or whole-grain oats.

Whole grains are a great source of fiber. Having fiber in the morning means “you’re not going to be having a hunger attack midmorning,” says Emily Dhurandhar, Ph.D., an assistant professor of kinesiology at Texas Tech University.

Numerous studies have also linked whole grains to a lower risk of type 2 diabetes, heart disease, and cancer. They may even help you maintain a healthy weight.

Researchers at Tufts University found that people who replaced refined grains (such as white bread or white pasta) with whole grains absorbed fewer calories and had a slight uptick in their resting metabolic rate compared with people who ate the same diet with refined grains.

Suss Out the Sugars

Even a whole-grain cereal isn’t so healthy if it contains too much added sugar. Kellogg’s Frosted Mini-Wheats, for example, is made from 100 percent whole-grain wheat and has 6 grams of fiber per serving, but it also has 11 grams of sugars, almost 3 teaspoons.

Compare that with Post Spoon Size Shredded Wheat, which has 0 grams of sugars per serving. (The American Heart Association recommends no more than 25 grams of added sugars per day for women, 36 grams for men.)

“If you want it sweet, add fruit or even a teaspoon of sugar if you need to,” says Maxine Siegel, R.D., who heads the food-testing lab at Consumer Reports. “But if you’re going to buy a sweetened cereal, choose one with no more than 8 grams of sugars per serving.”

If you choose a cereal with the fruit already added, don’t assume that all the sugars come from the fruit. “Check the ingredients list for added sugars, such as high-fructose corn syrup, brown-rice syrup, and honey, to name a few,” Siegel says. “All types of added sugars have the same health drawbacks as table sugars.”

Pay Attention to Protein

Having protein in the morning may help keep blood sugar steady and aid weight control. Cereals usually have 3 to 4 grams of protein per serving; some contain 6 or more grams.

Pour on cow’s milk (or certain soy milks) and you’ll add about 3 to 4 grams per ½ cup. (Almond and coconut milks have practically none.) Or top your cereal with plain yogurt, which will add about 4 grams per ½ cup.

Watch Your Portions

In a test, Siegel’s team asked consumers to fill a bowl with the amount of cereal they would typically serve themselves. About 92 percent poured too much—24 to 282 percent more than the serving size on the box.

“A double helping of cereal can give you more fiber and protein, but it can also bump up the calories, sugars, and sodium,” Siegel says. So grab your favorite bowl, pour out the amount you usually eat, and measure it. Then do the math so that you know what you’re really eating.

Editor’s Note: This article also appeared in the July 2017 issue of Consumer Reports on Health

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