Just in time to kick off the eating season, we will turn our attention to the recently most vilified macronutrient, carbohydrates. Currently, carbohydrates provide 40% to 60% of energy in the American diet and usually come from processed packaged foods or foods of convenience as more than 80% of Americans get their meals outside the home. This disordered eating balance has led to many lifestyle diseases such as obesity, heart disease, nonalcoholic fatty liver disease and others. We will discuss why this is so.