Method for losing weight...why hasnt it been suggested?

Ingesting a tape worm. It may have certain negative side affects like excruciating fever for two days but if it was surgically removed after it took effect, then why isnt it regarded as an effectve method for weight loss. Its capable of reducing the host's weight by 20-30 pounds in such a short time period. I think the negative effects are negligible compared to the benefits.