Hi, @spbeckman (Scott). I do, in fact, refers to the percentage of calories from which macro they were taking in. 40% from carbohydrates is not considered low carbs. It varies from guidelines but for example, ketogenic diet, the percentage of calories for it is 70% from fats, 25% from proteins and 5% from carbohydrates. Okinawan people eat mostly carbohydrates which constitute 85% of their daily calories. The percentage only explained macros and not micros. It is one way to look at other than the "calories in calories out" concept in which you will be concerned about the total calories and not calories of each macro.