Sugar is very sneaky. It appears in all kinds of forms and masquerades under many different names. For example, have you ever read one of those jam labels that says, “All Fruit” or “Spreadable Fruit” on the front? Turn the jar over and read ingredients. Most likely you’ll find juice concentrates (often as the first ingredient) and maltodextrin — both forms of sugar.
According to Environmental Nutrition foods with all of the following names are sugars (these are common sources, there are other sugars not listed):
High fructose corn syrup
Fruit juice concentrates