Yes vegans need to supplement certain things.
But in reality it doesn't really matter if your vegan or your just on a regular diet because most people that do eat meat would need to supplement about the same things as a vegan should since there is almost no nutritional value in our food what so ever any more.
I'm going to throw one out there, the famous B12. There are some vegan sources for this not many people know about but in general vegans and vegetarians need to supplements this.
But meat eaters would need to supplement this too actually because a lot of people that eat meat are deficient in B12 as well.
Mac Jesus will probably jump off his chair for this one and yell I'm stupid because of this remark but if you really understand what B12 is, where it comes from and how it (is supposed to) end up in the meat you'll figure out that people who eat meat are deficient in this vitamin too.
Personally I think all the growth hormones , antibiotics and other medicinal cocktails and preservatives added in meat and milk far outweigh any benefit anyone here can mention. Yes there is some meat and milk out there that doesn't have these things added to them but how many of you really eat only biological grass feed beef or drink raw milk?
There is also a reason why 75% of the planets population is lactose intolerant.. The other 25% is mainly white Europeans and White Americans. And they can only tolerate milk because of a mutated enzyme. So people who tolerate milk are actually mutants.
Then there's also meat is next to sugar about the most acidic thing you could put in to your body. Which in it's own right can lead to so many problems.
And even though for most people it's still an ongoing debate whether we humans are supposed to eat meat or not, the sheer quantity we eat today is way to much and this is indisputable. This also reflects on our society.
Personally I've never judged anyone on their dietary choice alone. That by itself would be stupid but if you want to be a little more responsible on your own actions and pass on a better living environment on this planet to your children you should take the quantity of meat you consume each day in consideration, but I guess that's not gangster enough.
I think vegans would only need to use creatine supplementation when they powerlift or bodybuild they actually look a lot healthier then 'regular' bodybuilders. I won't post any photos since many here seem to be homophobic. Don't know if they take creatine supplements though. But since I don't do these things I don't take creatine supplements. I do go to the gym and I know many people on a diet with meat that actually take creatine supplements. You'd think they would get enough from their diet alone.