> If somebody claims that a vegan diet is healthier and better, I would expect some facts that support that claim at least.
The links I provided show studies that support that claim. If you are interested in more, please visit nutritionfacts.org.
> Do you know somebody that became centenary following a strict vegan diet?
Google Dr. Ellsworth Wareham. 101 old, vegan for the last 50 years, retired surgeon who worked until age 95 and is still very active. I'm sure there are others, but again, this alone doesn't prove anything when it comes to which diet is healthier.
Since a very tiny percentage the world is vegan, of course you will find more centenarians who are not vegan, that's why you need to look at studies that control for this and other factors.
> This people either faked their veganism or were really very ill.
If you are thinking about b12, which is the only supplement most vegans today are advised to take, keep in mind that this vitamin is produced by bacteria. Before we washed our foods and lived in sterile environments, b12 was not a problem.
Abstinence from animal products dates as far back as Pythagoras with his Pythagorean diet, at least.
> On the other hand, reaching 100 years with a mediterranean diet or a Japanese diet based in marine food has been proved as uncommon, but perfectly possible, with dozens of cases reported at least.
The Okinawans, whose life expectancy was among the highest in the world, ate significantly less fish than the rest of Japan. Their staple was sweet potatoes (69% of their calories)[1].
[1]- https://en.wikipedia.org/wiki/Okinawa_diet
