Nope. Primarily insulin is used to help digest 10,000 to 20,000 calories per day, and TRT (testosterone) from doctors.
Most of the Mr. Olympias have interviews on Youtube. They usually don't give the dose so that amateurs don't emulate them, but otherwise are pretty open about it.
(I was one of the strongest and biggest Gold's Gym members in the Bay Area just by sleeping 8 hours a day and going to the gym every 3 days in my 20's and 30's, so you can get results naturally if that's your #1 priority for a few years. For example, I maxed out all of the machines.
Note that if you're an engineer, make sure you have a sensible goal beforehand, since nobody needs a super-heavyweight engineer.)