Leptin is the hormone that tells our brains, “Okay, I'm full. I don't need to eat anymore and now I'm going to increase your metabolism.”  Dr. Martin shows listeners in today’s episode the stark difference between 1 pound of fat, versus 5 pounds of fat. He stresses the difference between them is because of insulin.  Leptin and insulin work together. When you eat crappy carbs and sugars, you end up developing insulin resistance. When this happens, your body makes more fat, and this causes more leptin to be secreted. Eventually, you develop resistance to leptin too!  A chain reaction is set off in our bodies… but there is good news! This resistance can be reversed, and it comes down to what we eat.