Pharmaceutical, nutraceutical, dietetic and nutritional compositions containing: a) glucomannan, b) Opuntia ficus indica, c) microcrystalline cellulose present a high gastrointestinal swelling index, which induces an immediate feeling of fullness, release of cholecystokinins and slowing of gastric voiding that prolongs the feeling of fullness. Associating the complex of three vegetable fibers with a mixture of freeze-dried mucilages increases its gastrointestinal swelling properties.