A lot of inexperienced vegetarians/vegans end up with nutrient deficiencies because they don't ensure that they are properly getting all essential vitamins or amino acids in their meatless diets. I'm not a dietician, but it's pretty safe to say that these people are not going to be the ones with reduced mortality rates. You cannot simply remove an entire food group from your diet without putting in effort into paying attention to the rest of your diet.
Some studies[1] show that pescetarian diets offer the lowest mortality rates. This diet still requires paying close attention to what you eat, but you are far less likely to have nutrient deficiencies.
This is one of the huge issues I have with diet-mortality studies. During the gluten-free trend a while back, there were many that suggested gluten-free diets provided health benefits. However, for the vast majority of people, gluten isn't really that special as far as proteins go. It turned out those "health benefits" were just the result of people with gluten intolerances actually paying attention to their diet.
Just to reiterate, I am not a dietician. Everything above is just my cynicism for studies that constantly fail to take into account that most people just don't care what they're eating. I would absolutely love to be proven wrong.
While that certainly happens, its not like you have to maintain constant vigilance. Most popular vegetarian diets are nutrionally complete (major exception being vitamin b12 for vegans is something to be very careful about).
Like yes, if you decide to only eat rice and nothing else it will be bad, but its not like you have to meticulously record what you eat every meal. Getting all essential amino acids is pretty easy if you eat like a sane person.
> major exception being vitamin b12 for vegans is something to be very careful about
Add to that list iodine, omega-3, zinc, iron, calcium, and vitamin D. All of these are essential nutrients that vegetarians need to include in their diet. Sure, they're easier to get than B12, but they can still be pitfalls if you're careless.
> Getting all essential amino acids is pretty easy if you eat like a sane person.
Yes. That's basically the entire point I'm making. Most vegetarians eat 'like a sane person' because if they don't then they will have issues very quickly. Having a diet with meat means you can eat more carelessly because you're less likely to have immediate issues compared to eating carelessly as a vegetarian.
What I'm asking for are studies that take this into account. Studies that aren't just asking people if their diet includes something. Studies that actually take into account the fact that most people that don't care what they are eating tend to eat meat.
Fwiw, I've been vegetarian for like twenty years, don't really track much of anything in terms of vitamin intake, and am doing just fine according to the last time I had blood work done. I eat eggs and beans and rice for protein, and cook on a cast iron for iron... And that's the sum of my thought on vitamin intake. My partner takes b12 supplements, though.
I do think there's a certain over estimation of how hard it is to not eat meat. It's really not.
Common nutrients that even non-vegetarians do not generally get from meat.
Iodine is usually from salt, Omega-3 is often vegetable oil and nuts, zinc is commonly in beans and grains, calcium and D3 is in milk (you said vegetarian not vegan), and more to the point, most people do not get vit D exclusively from diet.
These are all things that non-vegetarians get in sufficient quantity from non-meat sources. So why would someone becoming a vegetarian suddenly stop eating these things.
> Having a diet with meat means you can eat more carelessly because you're less likely to have immediate issues compared to eating carelessly as a vegetarian.
While i agree in general, your definition of "careless" is so ridiculous that I think meat eaters would rapidly be in trouble if they were this level of careless.
