According to Wiley Brooks, a young girl managed to pull this scam for 10 years.

It's worth mentioning that no Breatharian has ever successfully passed any sort of scientific evaluation. In the rare circumstances that one has ever agreed to any sort of monitoring they were either discovered to be secretly trying to eat food or attempting to be "legit" which results in their near death, after which they claim that being watched or observed somehow effected their Breatharian abilities or some nonsense.

Dick Gregory believed in this.