t depends mainly on your level of pride/humility.
Making a decision to try the vegan diet means going down the rabbit hole of taking responsibility for your own nutritional status, as well as (usually) taking some kind of ethical stand.
Both of these will put you in conflict with people who have different ideas. People tend to identify with their lifestyle and ethical choices to the extent that a challenge to them is seen (unconsciously) as an existential threat. This is why no matter how chill you are about it, you will end up making someone angry.
How seriously that affects you depends on your own level of ego.
The other way that pride/humility will affect the “dangers” is that nutrition is an unfinished science. People get it wrong ALL THE TIME.
You will go on a journey of trying to figure out what to accept and reject and what to rely on. Uncertainty is uncomfortable, so most people stick to the first position that seems to reinforce their existing ideas. The trouble is, the first position you come to will probably not be sophisticated enough. To do yourself and your new choice justice, you’ll need to stay open to new ideas for much longer than is comfortable, and apply critical thinking when all around have ceased to do so.
Here’s an example of some levels of nutritional sophistication that most of us (me included) are somewhere in the middle of. Starting with least sophisticated:
1. You have to eat meat because we were made to do it and otherwise you’ll probably die when winter comes around (someone literally told me this once).
2. Well I didn’t die, and I read that meat is bad for you! Just eat plants! They give you every nutrient you need.
3. Oh snap forgot about B12. Ok take a supplement and just eat plants!!! Yay China Study! Live forever!
4. Huh. Long term vegans often have low levels of really important nutrients in their blood. And the China Study has mixed interpretations. Maybe I should eat some chicken..
5. My vegan friends still have health problems, just different ones to my meat-eating friends. Maybe it’s all individual. I dunno what to think!
6. Ok probably you can really carefully supplement your way to something that should be healthy (and is way way better than what everyone else is doing anyway) and still not eat animal products at all. Missing out on some interesting nutrients but whatever. I really should start making a list. Or my own reference book..
7. How do I know I’m doing it right? What is MY nutrient status in my cells right now? How does my genetics play into how I metabolize food? Why did I take the red pill in the first place??
You could do the same thing for ethics, but you get the idea.
I wrote about some of the considerations towards the latter end of this spectrum in my Quora blog article: Are vegan diets bad for fitness?
(I’m just collecting and commenting on links from studies, I’m NOT a doctor or nutritionist. This isn’t medical advice.)