Pyrocatechol sulfate, a phenolic metabolite found in human plasma, is associated with the intake of specific foods such as berries and the state of the gut microbiome. It serves as a potential urinary biomarker for kidney function, dialysis clearance rates, whole grain consumption, and regular coffee intake. Additionally, in conjunction with other phenolic sulfates, pyrocatechol sulfate plays a role in regulating various biological functions, including those related to brain health and the rhythmic beating of cardiac cells.