The sugar listing on a food label is very deceptive. It includes not only the "added sugar" to a food (sugar, syrup, HFCS, honey, etc), but also the sugar that is naturally found in things like fruit, milk, yogurt.
So when you are eating strawberry yogurt, it is really difficult to determine how much of the sugar listed on the label comes naturally from the milk that was used, naturally from the strawberries, or is added with sugar and syrups to make the product sweet.
This USDA listing is great. It breaks it down by foods, so you know exactly the amount of added sugar to the food. It may help with your manual tracking. www.megaheart.com/pdf/addedsugars.pdf
I hope in the future that the food label sugar listing just includes "added sugar"---this would make it much more meaningful and helpful to the consumer
Your SP Registered Dietitian