An Evolutionary Liability

People in Cameroon use a plant they call “forget” (oubli). This African vine (Pentadiplandra brazzeana) makes a small protein that mimics the taste of sugar. Legend has it that children given berries from this plant forget the milk of their mother. Several other African tropical plants have evolved powerful peptide mimics of sugar. Similarly, leaves of the South American stevia plant are added to mate dulce, traditionally made by the Guarani Indians of Paraguay, and they have also become the basis for a popular low-calorie sweetener. See stevia. Modern synthetic chemistry has tried out a variety of artificial sweeteners with mixed results. See artificial sweetners. Ironically, the tsunami of artificially sweetened drinks and foods seems only to have accelerated obesity trends. Furthermore, concerns have been raised that dissociating sweet taste from energy may, as University of Washington epidemiologist Adam Drewnowski and colleagues put it, “disrupt the balance between taste response, appetite and consumption, especially during development.”