Humans are not designed to eat meat.....we are herbivourous. That in itself is probably to a large part the cause of many of our health problems. Next add in the countless antibiotics and hormones given to factory raised animals and we now have more problems.
We're actually omnivores but part of the mammalian order Carnivora.
Which is different from our dietary characteristics.
The Carnivore order includes not only herbivores and carnivores, but also those in between in terms of diet: frugivores, gramnivores and insectivores for example.
We (humans) are dietarily omnivores: capable of eating either plants or animals. Like for example the chimpanzees who will eat either.
It's only the apes for example at the extremes of size end: the smallest tend to only eat insects with limited amounts of greens, and the largest who tend to eat mostly fruits and greens.
We're more opportunistic dieters who will eat greens or fruit if available, or meat if freshly killed (either by us or someone else if we can drive them away and steal their kill).
There is no physiological evidence now or in our past that we are best adapted to function as vegetarians