Coffee consumption and cystatin-c-based estimated glomerular filtration rates in healthy young adults: Results of a clinical trial

Recently it has been reported that the estimated glomerular filtration rate (egfr) is higher in habitual coffee consumers than in noncoffee consumers. however,the causality remains unclear. therefore,we conducted a clinical trial to investigate the effects of coffee consumption on kidney function. nineteen asymptomatic nonsmokers aged 21-27 years old participated in this study. they consumed coffee (18 g coffee beans/450 ml per day) or green tea as a comparator for 2 weeks in a crossover design. although creatinine-based egfr was not affected after consuming either beverage,all cystatin-c-based egfrs determined using five different equations were significantly increased after coffee consumption (means: 5.0-7.7%),but not after green tea consumption (means: 0.1-1.6%). serum adiponectin and magnesium levels increased significantly after coffee consumption (means: 13.6% and 4.3%,resp.),but not after green tea consumption. these findings suggest that even a short period of coffee consumption may increase cystatin-c-based egfr,along with favorable changes in serum adiponectin,in healthy young adults. © 2011 masafumi saito et al.