The present invention provides a method and composition for ameliorating or reducing the symptoms and signs and for the treatment of obesity, diabetes, and related conditions in a mammal in need thereof, said method comprising administering effective amounts of a pharmaceutically acceptable composition comprising a mixture of probiotic microorganisms with distinct but complementary pathways of carbohydrate metabolism, for a time sufficient to ameliorate, reduce or treat at least one sign or symptom of obesity, diabetes or cardiovascular disease. Compositions having the desired properties, and methods for their use in pharmaceutical and nutritional formulations, are provided.