is it healthier to eat no meat?

[emjay]

I don't know about in general (except I personally couldn't imagine going vegetarian/vegan but that's just me) but there is one specific case in my family of a long term vegetarian having to go back to eating meat for health reasons, but granted they have other, complicating, health issues involved (which they're happy for me to talk about here), ie ME and it is assumed, long covid. Meaning they basically have very little energy most of the time and need to rest often. Eating meat again was to address deficiencies in iron, B vitamins, and zinc, that were thought might contribute to these other problems, but they say though it has helped to some degree, it hasn't solved the other health problems, which sadly remain an ongoing mystery since they always used to be so full of beans and now its a struggle for them even getting up the stairs etc.