Everyone’s physiology is different

This is the funny bias in today’s world; everyone accepts the fact that everyone’s physiology is different, yet, we still say things like:

It is hard to digest meat and beef.

Perhaps for individuals with weak constitutions, it is difficult for them to process and digest beef or meat.

Or, we say things like

“Eating meat is bad for you”.

How come no one ever says

“Eating vegetables and fruit and grains is bad for you”.