The multi-faceted process of aging encompasses various human pathologies such as diabetes, hypertension, neurological and cardiovascular diseases and cancer among many others. The hallmarks of aging has broadened the scope of eligible interventions aimed at delaying aging. Among the scores of anti-aging strategies, dietary restriction (DR) intervention has opened gamut of physiological benefits for humans. In this review, we elucidate briefly the two strict DR approaches practiced among humans especially for weight loss, but additionally for its metabolic benefits and lifespan elongating effects. Calorie restriction has been tried in diverse model organisms including humans, but CR has been challenging for humans due to its adverse effect. We discuss the metabolic pathways operating in case of intermittent fasting (IF) and calorie restriction (CR). Lastly we review a vital mechanism observed during fasting, ketogenesis, and scrutinize the latest emerging dieting trend keto diet with reference to IF.

衰老的多方面过程包括各种人类疾病，例如糖尿病、高血压、神经和心血管疾病以及癌症等。老龄化的特征扩大了旨在延缓衰老的合格干预措施的范围。在众多抗衰老策略中，饮食限制 (DR) 干预为人类带来了广泛的生理益处。在这篇综述中，我们简要地阐明了在人类中实行的两种严格的 DR 方法，特别是为了减肥，但另外还有其代谢益处和延长寿命的作用。已经在包括人类在内的多种模式生物中尝试了卡路里限制，但由于其不利影响，CR 一直对人类具有挑战性。我们讨论在间歇性禁食 (IF) 和卡路里限制 (CR) 情况下的代谢途径。