There are multiple types of fasting: short fasts, long fasts, intermittent fasts, group fasts, caloric restriction, and so on. Fasting means that you are abstaining from foods and drinks for a set amount of time. This can include restricting specific types of foods or drinks. Caloric restriction (CR), on the other hand, is a reduction of caloric intake with the goal of improving health and slowing ageing while avoiding malnutrition. This approach normally does not reduce essential nutrients to below recommended amounts.