A method for administering pyruvate is disclosed which comprises administering a therapeutically effective amount of a pyruvate precursor to a mammal in the form of pyruvamide or a pyruvyl-amino acid. The pyruvyl-amino acid is preferably selected from the group comprising pyruvyl-glycine, pyruvyl-alanine, pyruvyl-leucine, pyruvyl-valine, pyruvyl-isoleucine, pyruvyl-phenylalanine, pyruvyl-proline and pyruvyl-sarcosine, and their amides and esters as well as their salts. Associated with the administration of a pyruvate precursor to a mammal in accordance with this invention are improved insulin resistance, lower fasting insulin levels, and reduced fat gain. Novel methods of synthesizing several pyruvate precursors are also disclosed.