You probably know Scott Jurek is vegan, too, as are a lot of long distance runners, so it can be done! It's not automatic, though- I spent the first few months tracking my nutrient intake to make sure I was getting what I needed as an athlete. There are some great online nutrient trackers, and I really think they're worth the time. Once you have a routine and a sense of what's enough, you won't need to track everything so closely anymore.
http://www.veganhealth.org/articles/dailyrecs has a quick list of nutrients vegans should think about. For me, I feel best when I'm eating a bit more protein and fat than most people need.
If your diet is sufficient and you still feel tired, try eating 7-8 small meals instead of 3 big ones. That made a big difference for me.
Natala,I was one of those people that tguhoht I would never be a Vegan, and then I had a heart attack when I was 40. My wife found your blog, and we started to read up on going plant based and being Vegan. My heart disease went away, and I will now be around for my children. My children will not have to get the disease that almost killed me. Now we eat things like tofu. Sure, I get shit for it, but I also know that all of those people will one day have to make a decision between getting over themselves and learning for themselves and changing what they eat. Again, thank you for all you wrote this year.Mike T.