I’m talking about before we figured out we could grow vegetables and fruits. Early humans are often shown as being fit and in shape, yet our diet pretty much only consisted of meat. We were hunters. So why the hell were they so fit? I thought a healthy diet mattered more than just being active constantly?
Do you mean they mostly ate “animals”? (“meat” is a modern supermarket product). And by “fit” do you mean “not dead”? And exactly which “early humans” are you talking about? “Animals” consist of meat, organs stomach contents, brain matter, bones, skin etc. If they ate all of those parts then they would likely be balanced enough, and they all would have craved and eaten whatever veges they could forage too, particularly in tropical regions where fruit would be abundant.