A new meta-analysis of 63 studies involving 3,484 participants shows virtually no cognitive difference between fasted and fed adults. Researchers found the performance gap was just 0.02 standard units, essentially meaningless. The study examined fasting periods from three hours to two weeks, with most lasting around 12 hours. Adults’ brains switch from glucose to ketones after 12-16 hours without food, maintaining mental performance. Fasting only hurt performance when people viewed food images, while neutral tasks showed no difference or slight improvements. The research confirms children still benefit from breakfast due to developing brains, but healthy adults show no cognitive impairment from skipping meals. The findings challenge decades of breakfast-promotion messaging and support intermittent fasting practices. (Story URL)