Mark Zuckerberg's training so hard for a potential MMA fight with Elon Musk that he's eating 4,000 calories EVERY DAY to avoid widening the huge size difference between the billionaires!
Zuck's been busting his ass training with some of the best UFC fighters in the world ... and even recently disclosed he installed an Octagon on his lawn!
In order to maintain his already slight stature, MZ revealed his McDonald's order on Threads, and it's a hefty amount of food for a 145-lb.