The principle that ginger black tea can lose weight is that it can make the body generate heat, improve metabolism, consume calories in the body and achieve the effect of losing weight. In addition, ginger can also help defecate and improve the symptoms of cold hands and feet. Black tea is fermented tea, which can keep the body warm, and the caffeine contained in it can expel excess water from the body and improve edema. Together, they can not only lose weight but also improve edema.