New research challenges the common belief that skipping meals compromises mental sharpness. A study published by the American Psychological Association in the journal Psychological Bulletin found that intermittent fasting is unlikely to cloud most adults' thinking in the short term.
Researchers analysed 71 existing studies involving 3,484 healthy adults, comparing cognitive performance between those who were fasting and those who had recently eaten. The average fasting period was 12 hours per day. The study examined memory recall, decision-making, response speed and accuracy.
Lead author David Moreau, associate professor of psychology at the University of Auckland, said: 'We were certainly surprised in one sense, as our results contradict the widespread assumption that fasting inherently compromises thinking ability. Across a broad range of diverse tasks, cognitive performance remained remarkably stable.'
However, the study noted some evidence that brain performance may be affected after 12 hours of fasting, and children showed noticeable declines in cognitive performance while fasting. Additionally, tasks involving food-related stimuli, such as pictures of food, led to poorer performance, suggesting hunger may selectively divert cognitive resources in food-relevant contexts.
Dr Moreau also highlighted potential physiological benefits of fasting beyond weight loss, including metabolic shifts that produce ketone bodies from fat tissue, which may confer health benefits and activate cellular repair processes linked to longevity.
