Have you heard of Vipassana meditation? They do something similar, but you are allowed to eat. It isn't for 1 day though, but for 10. Link here - https://www.dhamma.org/en/
I'd definitely recommend doing a 1 day retreat before diving into something longer - some people suffer psychotic breaks and other challenging meditation experiences.
I've been to a ten-day retreat, reportedly days 3/4 are the most common ones for something to happen. The organisation linked by GP actually doesn't accept applications for the one-day retreats unless you've previously completed a ten-day one with them.
Regular meditation instead of overdoing it is much healthier.