During the holiday season, it can be tough to find a reason not to have that third cookie. After all, your bathing suit isn’t threatening to reveal that extra jelly roll around your middle, and it’s all part of the seasonal fun, right? Well, recent research might just give you a more convincing way to turn down all of the sweets sitting around the house in December, and the added bonus is maintaining your figure come January. Australian research found that rats who were fed a diet high in sugar and fat exhibited symptoms of memory impairment when compared with a group fed a healthy diet. The sugar had caused swelling in the brain, particularly in the hippocampus – where memories are maintained. This inflammation kept it from functioning (read: remembering things) at its typical level. And the swelling didn’t automatically go down when the rats cut it out with the cookies. It took about three weeks for the brain activity to return to normal. Just remember that fact when you’re reaching for another slice of cheesecake this Christmas.