Abstract: This invention relates to methods comprising administering to a subject a dietary composition for modifying cellular metabolism, metabolic production of reactive oxygen species and the resulting level of reactive oxygen species. The invention is drawn to a method comprising a combination of carnitine, lipoic acid and polyphenol, which has the effect of enhancing metabolism and reducing oxygen species at the same time. The invention is also drawn to a method of oral administration of carnitine, lipoic acid and polyphenol to a mammalian host, at an effective dose necessary to affect enhanced metabolic processes and reduced oxygen species in animals including humans.