A Japanese study found that eating ice cream right after waking up led to improved mental performance, quicker reaction times, and a surge in brain-activating alpha waves. Researchers think the cold shock may jolt the brain awake—like an edible alarm clock—while the sugar delivers a quick burst of energy. Though the study didn’t compare it to other cold or sweet breakfasts, it suggests that your morning scoop might sharpen your mind... at least temporarily.