100 grams of blueberries contain just 5 grams of sugar. That's less than one-third the sugar in 100 grams of grapes (17 grams). Blueberries are also chockful with micros, including phytos. Eating a few grapes is fine for people without a metabolic disorder. Those with metabolic disorders should be aware of the quantity consumed and the effect it has on their blood glucose levels.

