Is intermittent fasting a metabolic loophole? A biohack that tricks your body into burning fat faster? Spoiler: no. Fasting isn't magic, and it doesn't change the basic rules of fat loss. But that doesn't mean it's useless. We're breaking down what fasting actually does in your body, why people think it works, when it might be helpful, and when it's likely to backfire. Plus, we'll tell you exactly who should avoid fasting altogether (hint: if you're training for performance, this probably isn't for you).