"Evidence suggest that the benefits of fasting may be an evolutionary adaptation resulting from long breaks between meals. Throughout human history, food scarcity and periods of fasting were common occurrences, and our bodies have likely developed mechanisms to adapt to these conditions.
During periods of fasting, the body shifts from using glucose as its primary source of energy to using stored fat for fuel. This can lead to a reduction in insulin levels, improved insulin sensitivity, and increased production of ketone bodies, which can have various health benefits.
Additionally, studies in animals have shown that caloric restriction and intermittent fasting can lead to increased lifespan and improved health outcomes, suggesting that these practices may have evolutionary benefits."