Your belly might be messing with your brain: Having a higher body mass index (BMI) could hurt your memory, new research from the University of Cambridge suggests.

In the study, overweight participants—those with a BMI greater than 25—scored 15 percent lower on tests of memory recall than normal-weight people (a BMI less than 25) did.

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The researchers aren’t exactly sure why a high BMI hinders brain performance, but they believe that fat—rather than, say, high amounts of muscle—is likely the key driver. 

It may have to do with fat’s effect on your insulin levels, says study author Lucy Cheke, Ph.D.

Too much fat spikes levels of this hormone out of control, which messes with the signaling between neurons in your brain. When this process is disrupted, your cognitive performance can take a hit, she says.

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How Memory Affects Your Weight
However, Cheke points out that it might not be that fat causes memory problems, but that people with poorer memories are just more likely to put on extra weight.

For instance, if you ate your last meal without really focusing on it—say, if you were distracted by something on TV or on your phone—you might be more likely to overeat the next time food is placed in front of you, she says.  

Related: The Eating Mistake That Doubles Your Chance Of Obesity

Your move, then, is to find a way to make your meals memorable.

“The better you remember them, the less hungry you’ll feel later on,” she says.

So go ahead and post your dinner on Instagram: Snapping foodie photos was beneficial to dieters because it gave them more time to reflect on the nutritional value of what they were about to eat, a study in the International Journal of Consumer Studies found. 

And the good news is, just because you’re lugging around extra weight now, your mind may not be doomed later. (Looking for a fat-loss program to help you get back in shape? Check out THE 21-DAY METASHRED—One Guy Lost 25 Pounds In Just Six Weeks!)

Research shows that other cognitive problems are reversible after weight loss, so the same probably applies to memory, too, says Cheke.