[Obesity and functional foods: are the new ingredients and products effective?].

: According to WHO data, obesity and overweight have reached the level of a world-wide epidemic: more than one billion adults are overweight, and at least three hundred million of them are obese. Obesity is associated with the main chronic diseases of our time. Obesity can reduce the life expectancy by 10 years and in Spain it is calculated that the health care costs account for 7% of the total. In the Spanish adult population, 14.5% are obese, and 38.5% are overweight. In the fight against obesity, the food industry has been incorporating new ingredients intended to help consumers obtain a suitable weight. In this study, we review the scientific evidence about some products and ingredients, discussing the fact that the main problem is their scant scientific support. Advertisers make much of supposed benefits which often lack a scientific basis, as in the case of products with a supposed effect on thermogenesis, metabolism and oxidation of fats, products which make people feel full, products affecting fat absorption, diuretics, laxatived, sedatives and substances affecting the central nervous system.