There’s a reason granola has become such a popular snack.

Several reasons, in fact. For one, it’s ultra convenient. Two, it’s versatile—a handful of granola can instantly upgrade a yogurt, cereal, salad, trail mix, etc. Three, it’s healthy. Hasn’t that always been the reputation of granola? That it’s a power snack for health-conscious yoga lovers and outdoorsmen? That might be the case, but the truth is that granola isn’t always necessarily healthy. Here’s what you need to know about granola.

Good Granola

The origins of granola trace back to 1863, when Dr. James Caleb Jackson created a health dish called “granula,” which consisted of unsweetened bran nuggets soaked in milk. But the modern definition of granola contains a lot of wiggle room when it comes to inclusions. Rolled oats might still make up the bulk of many recipes, but granolas can now include nuts, dried fruit, chocolate, seeds and a number of other ingredients. Granolas vary widely in terms of nutrition facts, yet they often share many of the same strengths.

Granola is usually much less processed than those colorful breakfast cereals, and it’s often tastier. Most granolas are high in fiber and protein, two important nutrients. A diet high in fiber has numerous benefits. According to the Mayo Clinic, it helps to normalize bowel movements, lower cholesterol levels, control blood sugar, maintain bowel health and aid in achieving a healthy weight. The Harvard School of Public Health states that fiber appears to reduce the risk of heart disease, diabetes and cardiovascular disease. One of the most interesting effects of fiber is that it slows down digestion, which helps you feel fuller longer after you eat. Many varieties of granola contain roughly 20 percent the RDV of fiber per 1 cup serving.

Protein is crucial for repairing and building muscle and has also been found to increase satiation. Many varieties of granola contain roughly 10 grams of protein per 1 cup serving.

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The benefits of whole grains, such as those used in most granolas, are also immense. Whole grain consumption has been linked to everything from decreased risk of heart disease to increased gut health and reduced inflammation.

All of these factors have helped granola gain a reputation as a health food. However, granola isn’t without its dark side.

Bad Granola

Fat content can be a concern with granola. Since the snack is so calorically dense (meaning it contains a lot of calories per volume), the fat content can get pretty high, even for healthier varieties. For example, Udi’s Natural Original Granola contains 24 grams of fat per 1 cup serving.

But you have to consider where that fat is coming from. A cup of raw oats contains 7 grams of fat right off the bat. This particular variety of granola also contains walnuts, pistachios, cashews and almonds. By their very nature, such nuts are high in monounsaturated fats. In moderation, monounsaturated fats help to reduce blood pressure and protect against heart disease. They can also help the body better absorb vitamins and more efficiently use protein. So when it comes to the fat content in granola, it’s really more about the source of the fat than the overall amount. To figure out whether much of the fat in a given granola is “healthy fat,” check out the saturated fat content. If it makes up a big chunk of the overall fat in the product, it might not be a great choice.

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But perhaps the biggest nutritional concern about granola is sugar. Since the ingredients can be so different from one granola to another, the sugar content can vary dramatically. For example, 18 Rabbits Organic Pecan, Almond and Coconut Granola contains 9 grams of sugar per 1 cup serving. Nature Valley Peanut Butter ’N Dark Chocolate Protein Granola, on the other hand, contains 30 grams of sugar per 1 cup serving. That’s roughly the same amount of sugar you get from eating two Frosted Strawberry Pop-Tarts. Isn’t granola supposed to be a “healthy” breakfast choice?

Here’s another problem with granola—the serving size. There’s a reason the nutrition facts cited throughout this article are based on a 1 cup serving. It’s because that’s how much most people actually eat—despite the fact many varieties list a 1/3 or 1/2 cup serving size. Andy Bellatti, a Las Vegas-based dietitian, recently told The New York Times that most people eat closer to one cup of granola per serving. Most granolas have small components in them, and a 2014 study found that cereals with smaller pieces were more likely to be overeaten than cereals with big pieces. Therefore, it’s frighteningly easy to overeat granola.

The Verdict

The serving size of granola might be the single biggest factor governing whether it’s healthy. If you’re eating granola by itself with milk, like you would with normal cereal, odds are you’re going way over the recommended serving size. Also, you’re probably getting more sugar—and possibly more fat and calories—than you intend to. Instead, think about adding a serving of granola to cereal, oatmeal, yogurt, fruit or similar dishes. This will help you bulk up your breakfast or snack with added fiber and protein, but it won’t take the sugar content through the roof.

It’s important to check out the nutrition facts of a granola before you purchase it. Look at serving size first so you have a good idea of how much you’re being recommended to eat. Next, peep the sugar content to make sure it’s not on par with junk food. Third, scope out the ingredient list. Granola’s a pretty simple food; if the ingredients list is largely unrecognizable, it might be best to look for another option.

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