tahere najafi dept. of nutrition, school of health, iran university of medical sciences, tehran shahriar eghtesadi dept. of nutrition, school of health, iran university of medical sciences, tehran mansour rezaei dept. of biostatistics, school of medicine and health research center, kermanshah university of medical sciences, kermanshah kyoumars daneshvar dept. of nutrition, school of medicine, kermanshah university of medical sciences, kermanshah