A one-cup serving of garbanzo beans contains 45 grams, or 35 percent of the the Institute of Medicine's recommended 130 grams of carbohydrates per day for adults. Eight of those grams are from sugars or refined carbohydrates. Twelve and one-half of those grams are from fiber, with the remaining grams coming from starches. Adult males 50 years and younger should strive for 38 grams of fiber per day and adult females in the same age range should strive for 25 grams of fiber a day.