You probably already know you should be limiting how much sugar you eat. Too much of the sweet stuff can increase your risk of developing cardiovascular disease, make getting diabetes more likely, and even help cancer thrive, studies have shown.

But when it comes to your body, not all sugars are created equal. Different kinds of sugar can affect physiological processes differently, and even influence how quickly your brain can function and deal with information, according to new research published in the journal Physiology & Behavior.

In the study, scientists gave 49 college students a drink that contained one of three common sugars people regularly consume—fructose (from fruit), glucose (found in fruits, soda, cabbage, pizza, etc.), and sucrose (found in table sugar, syrup, cookies, cakes, etc.)—or a placebo over a 16-week period. After each beverage, the researchers tested the frontal lobes of the students' brains with cognitive tests focusing on response time, math, and mental interference.

Their findings? The students who drank glucose or sucrose performed significantly worse than those who drank fructose or the placebo.

"Overall, these results indicate that cognitive effects of sugar are unlikely to be mediated by the perception of sweetness," according to one of the study's authors. "Rather, the effects are mediated by glucose. Further research should systematically assess effects of dietary sugars on other cognitive domains, such as memory, to give further insights on general cognitive effects of sugar consumption.

Still, that doesn't mean that all sugar is bad for your body—check out this primer on what types of sugar to eat and when.