Some experts claim that short fasts can improve health and fat loss. Proponents of intermittent fasting reject the idea of eating regularly. Many claim better health and fat loss by intentionally skipping meals and sometimes going entire days without eating.

There are various forms of intermittent fasting (IF); alternate-day, modified fasting, whole-day fasting, time restricted. What are the effects on fat loss? What about body composition and muscle mass? How does it work with intense exercise training? What about exercise performance?

In this article we review the science-based evidence on the IF protocols and their effects on fat loss, body composition and exercise performance. We take a look beyond the claims on social media to see what has actually been reported. To evaluate the evidence that may support the claims.