Potential Effects of
β-Carbolines on Human Health
The complexity of coffee health effects has increased since its recognition as a major dietary source of β-carbolines, a chemical family with several biochemical properties. However, research on harman and norharman have registered conflictive results, with neuroprotective and neurotoxic effects, mutagenic and antioxidant activities, among others. Although most of these properties have been observed with higher doses than those potentially achieved under daily ingestion and endogenous synthesis, human ingestion is highly variable, depending on dietary habits and environmental factors such as smoking. Additionally, individual enzymatic differences influence β-carbolines endogenous synthesis and metabolism, enabling their conversion into both protective and deleterious metabolites, and making it very difficult to achieve conclusions derived from their presence in the human body. Recent studies with lower concentrations of β-carbolines are showing promising results but β-carbolines' part in human health is still to be clarified.