Is it possible to lose weight fast?

In the wealthiest circles of Victorian England, dieters would swallow an unhatched tapeworm and let it grow inside them by consuming undigested meals. And while modern fad diets aren't usually this extreme, they do promise similar results; specifically, losing weight fast. So, are there any fast diets that do work? And are any of them actually healthy for you? Hei Man Chan investigates. [Directed by Avi Ofer, narrated by Pen-Pen Chen, music by Salil Bhayani, Suola Zhu].