Effect of Black Coffee on Fasting Metabolic Markers and an Abbreviated Fat Tolerance Test

Objectives Common clinical recommendations direct patients to report fasted when blood work (e.g., triglycerides [TG], glucose [Glu]) will take place, which typically excludes black coffee consumption. Despite its negligible calorie content, caffeinated coffee increases fatty acid mobilization. However, whether this effect meaningfully alters fasting metabolic testing or influences the results of a fat tolerance test is unclear. We investigated whether allowing black coffee intake within a fast prior to blood work affected fasting TG and Glu, as well as the postprandial lipemic and glycemic response following an abbreviated fat tolerance test.