Bioavailability of anthocyanins: Gaps in knowledge, challenges and future research

Anthocyanins are naturally occurring bioactive compounds that are extensively distributed in plant-derived foodstuffs and, consequently, largely consumed by humans. The consumption of foods rich in anthocyanins is related to decreased risks of developing cardiovascular disease and cancer. Despite the beneficial properties of anthocyanins, their effectiveness at preventing or treating a range of diseases depends on their bioavailability. Scientific developments have produced some methods that simulate the digestion process, facilitating an improvement in our knowledge of anthocyanin bioavailability. Recently, new in vivo and in vitro models simulating digestion have been described, which contribute to a better understanding of anthocyanin bioavailability, but each bioassay has inherent advantages and limitations. This critical review comprehensively summarizes the existing knowledge about the main methods applied to assess the bioavailability of anthocyanins, their related challenges and future research trends.