Artificial sweeteners are basically manufactured sugar alternatives. They are beneficial as a replacement to satisfy that 'sweet tooth' without the added calories and carbohydrates that comes with forms of Sugar. For example, 1 teaspoon of Sugar holds approx 16 calories and 4 grams of carbohydrates. The same amont of an artificial sweetener would contain virtually zero calories.
However, artificial sweeteners lack the benefits inherent with natural sweeteners like Stevia. These benefits include carotenoids, flavonoids, and other plant substances that have antioxidant properties. What makes Stevia excel as a natural sweetener is that it offers these benefits along with zero calories and zero carbohydrates, which isn't always the case with other natural sweeteners. Plants and herbs often contain fructose which effects blood sugar levels however Stevia sweetener is unique in that is does not contain fructose.