If people burn more fat on the days they exercise before eating, rather than afterward, why doesn’t this translate into more weight loss? A systematic review and meta-analysis on exercise timing for fat metabolism found that exercising in a completely fasted state may work best. The Japanese team that published some of the seminal work in this area went as far as to assert: “If exercise were a pill to burn body fat, it would be effective only when taken before breakfast.” Surveys show few people exercise before breakfast, though. Before asking people to make the switch, we need to make sure that these tantalizing 24-hour results translate into weight loss over the long term. There’s a solid theoretical basis, but you don’t know until you put it to the test….