No, black coffee in America and Japan is beneficial to the contraction of blood vessels and can promote the metabolism of the body. Moreover, the caffeine contained in coffee can help the human body burn subcutaneous fat, which is also beneficial to lose weight. Therefore, for people who lose weight, some black coffee can be properly cited to help them lose weight, but in normal times, we should also pay attention to controlling their dietary intake. If they eat too much, they should also strengthen exercise and lose weight only through black coffee, which is not obvious. Therefore, slimming black coffee in the United States and Japan is not fraudulent.