40-Geranyloxyferulic [3-(40-geranyloxy-30-methoxyphenyl)-2-trans-propenoic acid] (GOFA) and boropinic acid have been discovered as valuable phytochemicals exerting notable pharmacological effects as cancer chemopreventive and anti-Helicobacter pylori agents, respectively. A reverse-phase HPLC-UV/Vis method for their separation and quantification was successfully applied to evaluate the presence of these natural products in extracts obtained from the pulp and the exocarp of white grapefruits of different geographical origin. The recorded concentration values showed a great variation between the different sources, being the species richest in both secondary metabolites the one from South America. The set-up methodology showed LOQ values able to selectively quantify both GOFA and boropinic acid. Results described herein depict a potential chemopreventive dietary feeding role for grapefruits.