As the weather gets colder you might be tempted to reach for a mug of hot cocoa, and a new study finds that might actually be a healthy choice. University of Birmingham researchers have found that consuming foods with lots of flavanol, which is found in cocoa, increases the drinker’s mental performance. Flavanols are a group of molecules that occur naturally in fruits and vegetables, and previous studies have shown they can improve brain health. This new report also finds flavanols stimulate brain-blood oxygenation levels, which can help people to think faster and perform cognitive challenges more efficiently.