Review on herbal tea as a functional food: classification, active compounds, biological activity, and industrial status

Most herbal tea infusions use edible medicinal plants as raw material and are consumed daily. Although herbal tea has a long history of health care applications worldwide, there is a lack of systematic research on the classification and functional nutritional value of various herbal teas. In recent years, the discovery of the rich biological activities and health benefits of herbal tea has become a driving force for researchers interested in its development as a functional food. However, the shortcomings of herbal tea products are not fully known. In particular, the quality evaluation system is not perfect, and there is insufficient data on the mechanism of action of herbal teas in their traditional uses. To better understand the functions and mechanisms of various herbal teas, this article reviews the classification, effective chemical composition, main biological activities, and mechanism of action of herbal teas. Finally, the current advantages, limitations, and direction of future development of herbal tea are determined and discussed.