If you eat a lot of fructose—like from sugary drinks—for just 9 days, even without gaining weight or eating more calories overall, your liver becomes less responsive to insulin, which means it keeps making sugar when it shouldn’t.

If healthy men eat 80 grams of fructose or table sugar every day for 7 weeks, their liver starts making and releasing about twice as much fat as before—but eating the same amount of plain glucose doesn’t do that.

Eating too much fructose—like the sugar in soda and candy—might mess up how your liver responds to insulin, even if you don’t gain weight or eat more calories overall.

Eating fructose (like in sugary drinks) makes your body store more fat around your organs and liver than eating the same amount of glucose, even if you’re not eating too many calories overall.

If you eat less fructose—like the sugar in soda and candy—your liver will make less fat, even if you don’t eat fewer calories overall. This can help reduce fat buildup in the liver, especially if you’re overweight or have fatty liver disease.

When you eat fructose (like in soda), your body burns more calories digesting it than when you eat the same amount of sugar from glucose (like in bread), because your liver has to work harder to turn fructose into usable energy.