If you became a mafist (don’t eat mammalian meat or possibly dairy), how would it effect your lifestyle and health?
As an ovo-lacto vegetarian (one who eats eggs and dairy), I have to say I hadn’t heard of this before. It sounds like what I’ve heard described before as ‘pescetarianism.’
But I guess the easiest thing to say about it is - it’s hard to say. One can eat a very healthy version of that diet, or a completely unhealthy and low-nutrition version. As I’ve heard it said before - potato chips and soda is a vegetarian diet. ‘Mafist’ also, in this case.
I don’t know because it would never, ever happen. I like milk and beef way too much for that. When I go to the fair I look at the steer and think, “Aww, you’re a nice fella. I bet you’d taste good too.”
I attempt to eat somewhat healthy, so I don’t eat a whole lot of red meat. I eat lean pork more often, but the bulk of my animal protein comes from poultry and fish… so the meat part wouldn’t impact me too much.
I couldn’t give up dairy, however. Yogurt and cottage cheese are a dietary staple for me.
My lifestyle and health have already been effected. 
As for how they would be affected, there’d probably be no change for the worse. I’ve gone without any kind of meat for a lotta years. I’d be loathe to give up cheese & butter if I went vegetarian again. Frankly, I’m too fond of pizza to give up cheese. But if I did I’d probably be healthier.
Mafism sounds like a preference based on the darkness of something.
Minimally. Chicken, fish, and eggs are still on the table. My sister stopped eating mammal meat in her early teens because it tasted too musky and absolutely nothing changed as far as her lifestyle and health. She’d just get the McNuggets instead of the Quarter Pounder.
Mammalian meat, probably not at all. Milk products? I’d probably lose weight from not eating cheese. With respect to difficulty, giving up milk products would be an inconvenience, though fairly minor. Giving up mammalian meat wouldn’t really be noticeable at all, since I rarely eat beef or pork or other mammals. I’ve got no ethical problems with it. I’m just cheap.