Not credible. Kuaishou Sisi, also known as Sisi, formerly known as Zhang Yan, is from Chengdu, Sichuan, Kuaishou celebrity, and entertainment anchor. The juice ingredients sold by Internet celebrity Sisi are fruit juices. Juice products cannot make you lose weight. They mainly reduce the water in the body through diarrhea, but cannot reduce the fat in the body. Losing weight is through diet control and exercise.