FastySlim Germany Do not expect any miracles to happen overnight as nothing will work out other than sweating out to burn them. Preventing cancer, the #2 killer, is a major concern and animal research has shown results of extracts of green tea prevented cancer of the breast, lungs,liver, prostate, skin and colon. human studies suggest that drinking 2 or more cups of green tea a day, reduced the risk of breast cancer by 50 percent and the risk of all cancers by 10 percent. I'll do my best to not overcomplicate what determines the fat burning efficiency of an exercise, and show you the exact process I use to assess exercises.