Most consumers still do not trust artificial sweeteners made in labs, but sweeteners derived from natural substances are increasing in popularity. These low-calorie sweeteners seem almost too good to be true. Natural sweeteners have not been studied as extensively as sugar and artificial substitutes, but the FDA considers them to be safe. It is important to note that some natural sweeteners undergo chemical processing, which could affect the nutrition of sweeteners. However, the Center for Science in the Public Interest expresses that natural sweeteners such as stevia and agave are much safer than aspartame and saccharin, which are believed to be carcinogens.