It is interesting how insulin can change our behavior and actually make us fat. When we eat carbohydrates or sugar or bodies respond by producing insulin. Insulin actually tells our body to store fat. The body responds by either becoming hungry or tired and lethargic. The idea of burning more calories than we take in is the common view on weight loss. Supposedly it is simple physics. The problem is the cause. People who are getting fat are taking in more calories than they are burning because there insulin levels are high. There insulin levels are high because they are eating an excess of carbohydrates. People who are fat not being lazy, the insulin response to the carbohydrates they eat makes them lazy.
From personal experience I was much more tired and lazy after I ate when I was eating the Standard American Diet. My life since switching to a ketogenic diet has totally changed. I have energy throughout the day and I rarely feel tired. All this is because my insulin levels are lower because I don’t eat too many carbohydrates. The human body really is an amazing thing once we start to figure it out.