Weight loss experts at Temple are trying to answer a big question: Do diet drinks help or hurt your effort to shed pounds?  They are comparing diet soft drinks to water to see which is better. Calorie-for-calorie, it should not make a difference."Some people think diet beverages, that's zero-calorie beverages, can have a sweet taste, which they do, and that sweet taste can go and lead you to pursue other sweet tastes and derail your dieting efforts," said Gary Foster, director of Temple’s Center for Obesity Research and Education.