I think a lot of depression has to do with the stresses of the world, we're generally expected to deal with such an enormous burden of stressful action, noise, juggling jobs and families, knowledge of world events etc etc. I think this causes many people who would not necessarily express depression under a less stressful life to develop depressive symptoms. Our modern life is really geared to cause people to become ill, both physically and mentally. Anything we can do to relieve stress in our lives will help, and I don't mean taking pills to cover up the root causes. Our way of life itself is unhealthy. Veg*ns in general I think are addressing some of these unhealthful aspects, and they are so often more in touch with their health in general than other people. I don't think this makes them depressed, but it may make them more aware of how they are feeling and reacting to things. I feel that veg*ans are taking steps toward a way of life which is really healthier, and addressing some root problems, such as our agricultural system and food supply.