What's the most amount of weight a person could gain in a day?

themedicalquestions.com says:

Any weight gained over a 24 hr period is nothing more than water that is retained or the actual weight of the food items that were ingested. The body does not increase body fat at any measurable rate in such a short period of time. Weight (fat gain) occurs when there is a caloric excess over an extended period of time.

Professor Threepwood says:

It totally depends on how smashed you are. Once I ate a whole munchy box to myself on the way home from the pub.
That cost me £4.99.
The taxi home cost me £7.40.
Got a rollicking from the wife when I got in, had to sleep on the couch and lost £1.21 down the back of the bloody thing!

All in I lost 13.60 pounds.

I feel fit as f...