A burger and soda go together like peanut butter and jelly, but you might want to reach for water with your next meaty meal. You’re probably well aware that sugary drinks aren’t good for you, but we’re not here to talk about those extra calories. Sugary drinks could affect your waistline way beyond what the nutrition label would tell you—and they’ll do even more damage if you pair them with the wrong food. This is what happens to your body one hour after drinking a can of soda.
Protein-packed meals mean you’re eating foods that help build muscle, which is great! But if you pair them with a sugary drink, you could do more harm than good.
Researchers had 27 adults eat four meals: Two had 15 percent protein—one with a sugar-sweetened beverage and the other with a sugar-free drink; the other two were 30 percent protein with the same drink pairings.
Drinking a sugary beverage with a meal led to lower fat oxidation, the process that starts breaking down fat in the body, according to the study in the journal BMC Nutrition. And the higher-protein meal had an even bigger decrease than the one with less protein. Basically, drinking a sugary beverage with a protein-heavy meal means you’ll burn less fat, unlike these foods that help you burn fat.
Participants actually did burn more calories after drinking the sugary drink than the one without sugar. But that metabolism boost wasn’t big enough to negate the calories in the drink.
In fact, a sugary drink could mean more calories even after your cup is empty. The extra calories didn’t do anything to help participants’ hunger—in fact, they led to bigger cravings later on. Getting plenty of protein without the extra sugar cut down on cravings for salty, savory foods. But when the high-protein meal came with a sugary beverage, the appetite for those foods came back.
“Our findings suggest that having a sugar-sweetened drink with a meal impacts both sides of the energy balance equation,” says lead study author Shanon Casperson, PhD, research biologist with USDA, in a statement. “On the intake side, the additional energy from the drink did not make people feel more sated. On the expenditure side, the additional calories were not expended and fat oxidation was reduced.”
So even though protein is good for you, pairing it with sugar could let those benefits slip away. If you’re starting a day with protein-heavy eggs, don’t make the healthy breakfast mistake of drinking sugary juice; stick with coffee instead.