The body’s energy consumption starts with glucose in the blood, and when the concentration of glucose in the blood decreases it consumes the body’s reserves of sugar, also known as glycogen. Normally, when the blood glucose concentration rises after eating, the body converts the glucose into glycogen for storage through the liver. When the body is in a state of hunger or cannot eat, then the glycogen stored in the liver is converted into glucose to maintain the blood glucose concentration. So, if you don’t eat it is the glucose in the blood that is consumed first, and then the glycogen stored in the liver is broken down and converted into glucose to maintain the blood glucose concentration. When the glycogen stored in the liver is consumed it begins to consume fat, and when the fat is consumed, it begins to consume protein. Therefore, it is very unhealthy to adopt a diet without eating to achieve weight loss. Healthy weight loss is to be a low-calorie, low-fat diet, but definitely not fasting, not eating, and requires enhanced aerobic exercise. Regular, effective aerobic exercise can increase glycogen and fat consumption to achieve weight loss.