I’m a vegetarian. I have been one since 1986. When I first became a vegetarian, I had to make almost all my own food from scratch. There was one brand of soy hot dogs, and it was expensive. I had a pressure cooker, and didn’t even use canned beans-- I actually bought in bulk, and cooked beans in the pressure cooker. I did my own seasoning, and didn’t use a lot of salt.
As it happened, I lived in a cold-water walk-up, and I walked or biked to get food almost every day, so I always was eating fresh vegetables, and that was part of the whole “thing.” I didn’t have a lot of money, but I had a copy of The Tao of Cooking from a used bookstore, and a gift subscription to Vegetarian Times.
I didn’t eat things that were packaged or made from mixes, because they nearly always had something I couldn’t eat in them. The unhealthiest thing I ever ate was a mac & cheese casserole I made with real cheese, sauteed onions (in olive oil), and chopped Roma tomatoes that my aunt grew in her garden. And I usually ate it with a side of seasoned beans, and something like carrot sticks.
As vegetarianism became more popular, there were so many (high in sodium) fake meats to choose from, and lots of packaged things that stopped having animal products in them. Wonder bread was OK. Oreos were OK.
Almost any diet that makes you pay attention to what you eat, cook from scratch all the time, and read labels is a good diet, for the most part. There are exceptions-- fad diets that aren’t balanced because they have too much of one kind of food, whether it’s meat, kale, or mangoes, aren’t good, but there’s nothing really special about veganism, vegetarianism, or eating meat, for human health, as long as the person preparing it knows how to make it a healthy diet.
The main difference among them is that when they are inadequate, they are in different ways: bad meat-based diets are usually full of a lot of crap, and have way too much protein and sugar, and lack fiber. Bad vegan diets lack protein, and have too much raw carbohydrate, and can cause indigestion. It’s actually kind of hard to screw up vegetarian right now, if you use some of the fake meats-- but not too many, and are sensible about sugar. But that’s just because of the number of people that follow the diet right now.
Even high protein, low carb diets like Atkins can be sensible, if you take them seriously, and choose lean meats, don’t over-consume cheese, choose fat-free dairy otherwise, and make sure that you eat plenty of the low-carb vegetables that are allowed on the diet. You really have to make sure you get plenty of fiber on this diet. In fact, one of the downfalls is how much “low carb” stuff is available commercially. The diet works because you cook mainly from scratch. When you rely on prefab low-carb commercial foods, you might as well not be eating “Low Carb” at all.
Humans are true omnivores. That means that there is no “natural” diet for us. There are certain things we do have to get through diet, such as vitamin C and most of the B vitamins. Unlike Pigs, humans cannot eat literally anything, because we can’t synthesize the vitamins we need.
Really, the only thing necessary for a human diet is that there be some variety to it. There are societies that survived without meat for several months out of the year, and societies that survived with only preserved and stored (as in, a root cellar) fruits and vegetables, and may have occasionally had fresh meat, but even had mostly preserved meat for a while. Perhaps there were fresh eggs and milk.
There have been societies that survived on tropical fruits and shellfish, and societies that survived on dairy products, bread, and garden vegetables.
There is no one single diet that is ideal for humans. There are a few humans with conditions or allergies who have to avoid certain foods, but that does not imply anything for people as a whole anymore than the fact that because some people get a rash if they are out in the sun too long, everyone should avoid the sunlight.
Eating a diet that is satisfying to you, and feels right to you will be healthy for you, because you will eat it.
I’ll give you an example: when I was a teenager, and my mother believed in a meat-heavy diet, and very rarely used any kind of beans, or grains other than wheat (bread) or white rice, I had iron poor anemia, and had to take iron pills. About six months after switching to a vegetarian diet, I didn’t need the iron pills anymore, and was no longer anemic.
I was eating whole grains, including whole wheat & rye bread, brown rice, I was eating a lot of beans, I was eating tofu hotdogs, I was eating larger portions of vegetables than previously, including broccoli, and leafy greens.
I became a vegetarian because I didn’t like meat, so when I had eaten meat, I ate very small portions of it. I didn’t feel satisfied after meals, so I wanted dessert. After becoming vegetarian, I felt satisfied after meals, and stopped eating desserts.
So, even though I wasn’t eating meat, which is thought of as the #1 food for iron, I was eating all sorts of iron-containing foods, and in big portions.
I just use that as an example of the fact that eating a diet that feels right to you can be healthy for you, while trying to force something on yourself can be unhealthy.
So really, I don’t think there’s an answer to your question, other than “Humans are natural omnivores,” and “Staying away from packaged food, while preparing from scratch is the healthiest choice.”
