“Surprisingly, metabolic activation of PhIP was inhibited by addition of caffeine in an in vitro assay.”
“The final combined incidences (adenomas plus adenocarcinomas) and multiplicity (No./rat) of mammary adenomas and adenocarcinomas were significantly lowered in the PhIP plus caffeine group (10%, 0.10) as compared to the PhIP alone value (40%, 0.50).”
“With regard to colon tumor development, on the other hand, rats given PhIP plus caffeine exhibited an elevated incidence (75% versus 15% in the control), whereas α‐tocopherol and TTAD had no effect.”