The 16/8 method, which involves 16 hours of fasting followed by an 8-hour window for eating, & the 5:2 method, which entails eating normally for five days and limiting caloric intake to 500–600 calories on two non-consecutive days, are one 21 slotsthe two most popular types of intermittent fasting. The physiological consequences of fasting intermittently are significant. Insulin levels dramatically decrease during periods of fasting, which encourages cellular repair and fat burning. Fasting also initiates autophagy, a process by which the body eliminates damaged cells and produces new ones. By lowering inflammation and raising metabolic markers, this improves general health in addition to aiding in weight loss.