Intermittent fasting is an eating pattern that involves alternating periods of fasting and eating. In other words, it restricts food intake to specific times.
There are multiple different approaches to intermittent fasting. Certain schedules only allow food intake during 8 hours of the day, whereas others restrict or reduce food intake to certain days of the week.
Furthermore, researchers have conducted meta-analyses to summarize the findings of these clinical trials on the health benefits of the various forms of intermittent fasting. These meta-analyses have generally focused on the association betweenspecific intermittent fasting methods and health outcomes.
As insulin levels start to decline between meals, glycogen in the liver breaks down to maintain blood glucose levels. More extended periods of fasting, such as those prescribed for intermittent fasting, lead to depleted glycogen stores in the liver. As a result, the body resorts to breaking down fat to sustain the normal functioning of the body and the brain.
There are two forms of alternate-day fasting: zero-calorie alternate-day fasting and modified alternate-day fasting.
Zero-calorie alternate-day fasting involves fasting on alternate days, with no calorie intake on these fasting days. In contrast, modified alternate-day fasting allows limited calorie intake on the fasting days.
The 5:2 diet involves fasting for 24 hours once or twice a week, whereas time-restricted eating involves fasting for at least 12 hours during the day.
