Beef, eggs and salt is all the human body needs to thrive.
Totally disagree with this @lambchop. I’d add liver as well, then you’re all set :D.
More broadly, I don’t think taking a partisan stance on any particular dietary regime is particularly helpful.
Different diets work for different people, and there’s probably more good than harm in trying various different things for a month or two and seeing how you feel – especially if you’re trying to address a particular health concern.
I’ve various been full carnivore, hardcore paleo, and currently I’m eating a ‘conventionally’ healthy diet (which includes wheat and other carbs) – they’ve all suited me at different times when I’ve had different health and fitness goals, and different amounts of mental/time capacity to devote to this sort of stuff.