Multidisciplinary experts in the areas of nutrition and health met in Chinchón, Madrid, on November 25-26, 2013 under the auspices of the Fundación para la Investigación Nutricional (Nutrition Research Foundation) and with the collaboration of the Madrid Regional Government's Health Ministry, the International Sweeteners Association and the Carlos III Health Institute CIBER of Physiopathology of Obesity and Nutrition. They analyzed the current status of scientific knowledge on low- and no-calorie sweeteners (LNCS) and developed a consensus Decalogue on their use; this constitutes the Chinchón Declaration. Sweeteners, including sugar, represent a subject of undeniable interest and are currently a popular topic, although areas relating to their safety and benefits remain unknown to segments of academia and the general public. The nature of LNCS makes them vulnerable to biased and even contradictory information. They are food additives that are broadly used as sugar substitutes to sweeten foods, medicines and food supplements when non-nutritional or non-caloric alternatives are needed. The Chinchón Decalogue is the outcome of a meeting for reflection and consensus by a group of experts with backgrounds in different scientific disciplines (toxicology, clinical nutrition, community nutrition, physiology, food science, public health, pediatrics, endocrinology and nutrition, nursing, pharmaceutical care and food legislation). The Decalogue includes different aspects of LNCS related to regulation, use, benefits and safety. In general, benefits of LNCS have been traditionally neglected in comparison with the tendency for emphasising unexisting or unproven possible risks. The need to strengthen research on LNCS in Spain was emphasized, as well as the need to educate both professionals and the public.