Simple Carbs vs. Complex Carbs: What’s the Difference?

There’s no question that America has a carb obsession. Carbs make up our morning bagels (white flour), fries at lunch (starch), and sweet afternoon lattes (sugar). On average, Americans consume 239 (for women) and 335 (for men) empty calories a day from added sugars alone. The excess of simple carbs, like sugar and white flour, contribute to weight gain, type 2 diabetes, and heart disease, according to the Centers for Disease Control and Prevention.

So should you give carbs the boot?

Let out a sigh of relief, because the answer is definitely no. The key is choosing the right kind of carb, according to nutrition experts.

“Simple carbohydrates are easily broken down by the body, which means that they also easily increase our blood sugar,” says Frances Largeman-Roth, RDN, a nutritionist in New York City. These make up the most commonly consumed carbs: white bread, regular pasta, and desserts.

But not all carbs are that simple (pun intended). Complex carbs, including whole grains, vegetables, and legumes, take longer for your body to digest so they have less of a spiking effect on blood sugar.

In a long-term study of men without a history of diabetes or heart disease, those who consumed the least amount of whole grains (a complex carb) actually had the highest incidence of type 2 diabetes. Similarly, a six-year study of more than 30,000 women found that higher intakes of whole grains, as well as fiber and magnesium (which are found in complex carbs but not simple carbs), led to a lower risk of type 2 diabetes. (Here are the top food sources of magnesium.)

“[Complex carbs] have more vitamins, more minerals, and mainly more fiber,” says Sandra Arévalo, RDN, a spokesperson for the American Association of Diabetes Educators. Eating more beans and legumes, high-fiber veggies, and choosing whole grains instead of refined grains are all ways to up your complex carb intake, according to Arévalo.

The reason lies in the refining. The bran left in whole grains, such as brown rice or whole-wheat pasta, packs in fiber that slows down digestion. A 2017 study in the European Journal of Clinical Nutrition found that whole-grain brown rice has a slower “gastric emptying rate” than white rice, which resulted in a lower glycemic response. (Learn more about why fiber is so essential for diabetes management here.)

When you make a habit of choosing complex carbs over simple ones, your blood sugar levels tend to be more stable. This can help prevent diabetes in the first place and help patients with diabetes manage the condition better. It may also reduce your intake of empty calories (which tend to satisfy in the moment, but leave you famished soon after), which could aid in weight management.

To learn more about balancing carbohydrates in your diet, here are a dietitian’s tips on counting carbs.