Plasma alpha-tocopherol and gamma tocopherol levels will be determined by means of reverse-phase HPLC analysis; total antioxidant capacity (TAC) will be determined using the ferric reducing-antioxidant power and advanced glycation end-products will be detected using total fluorescence at 335/385 Ex/Em. Advanced oxidation protein products, carbonyl products, erythrocyte creatine and interleukin 6 will be also determined.