Fasting and Experimental Animals, Detrimental or Positive

Fasting is defined by not ingesting food and caloric beverages for periods ranging from 12 hr to 3 weeks. Fasting is an integral part of many religions. For instance Muslims, fast from dawn until dusk during the month of Ramadan, and Christians, Jews, Buddhists, and Hindus traditionally fast on special days. Fasting is different than caloric restriction (CR), in which the meal frequency is maintained but the daily caloric intake is reduced chronically by 20%– 40%. Fasting results in ketogenesis and exerts significant changes in metabolic pathways and cellular processes. Investigations on experimental animals and new findings from human studies indicate that fasting may provide effective strategies for weight loss, delay aging, and optimize health. Here we review the fascinating and potent effects of fasting, and intermittent fasting (IF) on experimental animals.