Obviously not news to anyone who has read Vegan for Life (or spent much time at VeganHealth.org), but an important talk for anyone who wants to be as healthy as possible (and/or, as discussed below, anyone who wants to help animals).
A quick summary:
After reviewing the reasons why vegetarians and vegans should live longer / have lower mortality than meat-eaters, Dr. Greger was shocked when he looked at legitimate research on actual vegetarians and vegans. He found (as also discussed here) our longevity wasn't better!
He then goes on to discuss, in great detail, the two main culprits: bad fatty acid intake (specifically, an omega-6 to omega-3 ratio that is far too high), and inadequate B12 intake (not a surprise to anyone who has known Jack in the past 20 years).
Of course, Dr. Greger doesn't discuss the fact that, according to the study discussed here, the majority of people who try to go veg end up quitting, with the number one reason being that they didn't feel healthy without meat. So not only do people who stick with a vegetarian diet not have better mortality, the majority of people who even try veg quit because of poor health.
All the more reason why this video -- and Jack's book! -- are so very important to anyone who wants to help animals! And why VO is so dedicated to honest and thorough nutrition information.