Okay, orange juice.
I mean, if you need a scene where Clark and Lois chatter for a minute so that the audience understands their relationship — and yes, this is the correct moment for a scene like that — then they have to chatter about something, and it might as well be orange juice.
It’s 1981, and the current fads in the United States include the Scarsdale Diet, the Beverly Hills Diet and the Grapefruit Diet, so given the need to generate some low-friction conversation filler, it’s natural that David and Leslie Newman would choose Vitamin C as the fashionable topic under discussion. There were other options, of course — Rubik’s Cube, Pac-Man, the Mount St. Helens eruption — but making Lois obsessed with fad diets helps to signal her acceptance of traditional gender roles, which I guess is what they wanted.
No, the really surprising thing about this sequence is the way that Lois has apparently set the land speed record for messing up her shitty little office.
Superheroes Every Day 