Protein deficiency is very rare even among long-term vegans and it's pretty hard to miss out on essential amino acids. As for "healthy fats, creatine, etc...", those can be easily supplemented, which is particularly important for vegans. Also note that meat eaters usually don't get enough healthy fats either.
Vegetarians have higher life expectancies (1-9 years), as also stated here.
This is the public group instrumental rationality diary for August 1-15.
Thanks to cata for starting the Group Rationality Diary posts, and to commenters for participating!
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