The Complete Protein Diet Bar from sports nutrition experts Optimum Nutrition is a great bar for anyone trying to build muscle or lose fat. In either case, you're going to want plenty of protein while keeping carbs super-low (except right after a workout when you need carbs). Complete Protein Diet Bar is right down your alley with 20 grams of protein and virtually no sugar - the carbs in Complete Protein Diet Bar are primarily from natural sugar alcohols which metabolize slowly and harmlessly in terms of metabolic effects. Try the awesome Toasted Coconut flavor.