I've no doubt it works. I've no doubt mindful eating works. I've no doubt that we could all be healthier by eating less meat and animals, but we should avoid any kind of prideful feelings that come from saying "My diet is better than yours."
A colleague of mine, who has taken up marathon running told me that the human being evolved because he could do things like expend energy on a long term basis running long distances, and somewhere in the world there are people who still catch their animal meals by chasing their meals until they drop. I think that's probably true too, but very non-Buddhist. As for myself, I've been swimming, using weights and doing some aerobic exercise.
I also think, given my recently renewed exercise regimen, that humans have evolved to expend physical energy. We simply need to be able to expend energy, in such a way as our bodies have evolved to help maintain our health as best as our lives and bodies permit. I think a more unsung issue, in terms of right livelihood is commuting long distances. How much do you commute?
I have a very short commute, and it affords me more time than I otherwise would have to be with my family. It also affords me the time to exercise to the point where my body mass index is in the bottom 20% of those my age and height. If you can structure your life to avoid a long commute I think that will go a long, and relatively painless way to a better livelihood.