An integrated plasma biomarker was devised that included plasma vitamin C , total cholesterol-adjusted carotenoids , and FRAP values , which better correlated with F&V intake ( r = 0.47 , P < 0.001 ) than the individual biomarkers ( r = 0.33 , P < 0.01 ; r = 0.37 , P < 0.001 ; and r = 0.14 , respectively ; P = 0.099 ) .