The sugar number.  I did some more poking around and found a source that says to stay under 37 grams of added sugar.  As it is “added sugar”, right or wrong, I am going to assume that the natural sugar in say an apple does not count.  The government site lists protein at 46 to 56 grams per day and 4700mg of potassium.  From what I’ve read thus far, I think the big things to concentrate on are Saturated Fat, Calories, Sodium, and Added Sugar.  You kind of get a lot of – fat bad, salt bad, sugar bad general information everywhere.