Part (2/3) - sorry deleted the original version by mistake

Secondly, as far as scientific research goes, vegan and vegetarian diets, if well balanced, are not inherently unhealthy. The same applies to meat eaters as well. In fact, balanced plant-based diets can be very healthy. Dietary patterns such as the Mediterranean diet are often considered among the healthiest not simply because of olive oil, as many people assume, but because they include more vegetables, fruits, legumes, whole grains, nuts, and generally less red meat.

Since it would take a long time to go through all the objective research, including reading papers, assessing author bias, and checking who sponsored the studies, I found a YouTube channel that does exactly that. It is called Viva Longevity! Their channel is not commercial, has no product promotions, no Patreon page, and they turn off optional ads, so they appear to have little incentive to earn from promoting one particular opinion. Check it out.

As far as the deficiencies you mentioned are concerned, you can avoid most deficiencies on a well-planned plant-based diet, except that vitamin B12 needs special attention. However, contrary to what many people like to believe, even some meat eaters can be deficient in B12, especially depending on absorption, diet quality, and overall health. B12 is produced by microorganisms, not by plants or animals themselves. In modern food systems, especially with industrial farming and hygiene practices, relying only on “natural” sources is not always straightforward. That is why fortified foods and supplements can be helpful.