Vegan, veggy, omnivore, primal, fasting.. just leave people in peace
I haven't been concerned with whether veggie, vegan, primal, or omnivore, etc. is "better" or "healthier" for a very long time. Years ago, back when the majority of people still thought it was weird as hell, I was vegan (before that vegetarian) for years. I was also very politically active, and I was certainly a bit too "missionary" in my thoughts and expressions way back then.
Since quite some years, I eat everything. Having a live-in partner that is vegetarian and three vegan friends I see and share some meals with fairly regularly, I eat those ways plenty too nowadays.
On at least on five separate occasions, and years apart, I spent two to six hours reading and learning about different diets, especially vegan, veggy and omnivore I read and watched plenty on. Some meta-studies, various government & WHO recommendations, well regarded essays and sometimes books and visual media. From Peter Singer to Gary Yourofsky (just watched his very recent long interview) to very pro-carnivore or primal books and documentaries, and also sources and media that held a position in between those two extremes.
My conclusion was and remains: it's all somewhat horseshit. And: "it depends!"
Who, how much, when, what genes, what quality, where do you live, in what climate, how active are you, how much body and muscle mass, how processed is it, how far did it come, what can you easily afford and buy and prepare? Each of those things, and many more can make such a massive difference, that saying anything akin to:
“The vegan diet or Mediterranean diet is best for everyone! or:
“XYZ (with animal or without animal products) is always bad or even the worst!”
Both are pretty crazy things to say much less advise. Especially unasked or unsolicited.
I've seen people become seriously ill from eating a purely vegan diet for long (I lived with very strict vegans for years). Sometimes the damage was not reversible, for example nerve damage due to severe B12 deficiency or a generally less robust immune system.
Yet there are also extremely fit and healthy vegan ultra-marathoners, combat sports professionals and body-builders. They tend to supplement and be very aware of their diet. I have no doubts that a vegan diet can be extremely healthy, if done right, by the right person.
I've also seen people who ate a massive amount of, or sometimes nearly exclusively meat and animal products, for 3 to 12 months and become much healthier, lose a lot of weight, have a lot of energy and get back vastly improved blood-work from their doctor. And the reverse, that the same diet had bad outcomes for other people.
I have personally tried a big array of diets at some point (for a few months to a few years): Atkins, no sugar, low carb, intermittent fasting, primal, vegan, vegetarian, onmnivore, water-fasting for a few days etc. I also really monitored if I felt any big changes in quality of life and health when I did one or the other. In the end, it turned out it made very little difference to me! Whether it was mostly animal or entirely plant-based, barring any extremes, it just didn't matter much at all.
With some of those ways of eating, I was able to lose a lot of weight well, with others less so or not at all, but in the end, the most important factors were always: “Calories in & Calories Out” and whether I had varied food with all the necessary nutrients. Of course YMMV with all of that! I would not presume to make a generalization out of my personal experiences.
Nobody informed would seriously argue that an average vegetarian or vegan diet likely isn't better for animals -and likely the environment too- than a heavily meat-based diet.
However, it is so absolutely pointless to argue about food and health choices, let alone give people a really hard time about theirs. I know a friend who almost every other day, wrote in a group chat about how:
"People should move more, not drink at all, eat healthy and eat very little or no sugar!"
One day I asked him why.
"Why are you telling the same handful of people in the chat group that, and repeating it over and over again for months? Do you think they do not know that, and have not known all of it for many years? That what you suggest is likely the healthiest, at least physiologically? And have you noticed how almost all of them drink (very) moderately, very likely eat more sugar than you and move a bit less and are okay with that? They are not responding in the chat nor changing.. Why not talk about anything else?"
To his credit, he always responds kindly to anything and did so now as well. Since I asked him those questions, he has very much toned down that health rhetoric and repetition.
My conclusion for me personally has always been: do what's good for you, and your body, health (including mental health!) and that which fits your life and circumstances...
Preferably try to do better, at least to a degree and when you can, for the planet and animals. And that's that.
For the rest: I try to shut up, truly enjoy my food and be grateful for all of it,.. and leave others alone!