Here's a really good blog that highlights information on centenarians from a wide range of disiplines (genetics, nutrition, fitness, psychology, etc.)
The link goes to a particular post on the "Blue Zones" but the blog as a whole has a ton of info on centenarians and longevity research.
The thing that always gets me is that virtually ALL of these centenarians that maintain their health and vitality eat very little meat. Certainly doesn't jive with the whole paleo concept and some research has implicated high protein intake with increased reactive oxygen species in mitochondria and increased mTOR activity. This may explain the overwhelming representation of vegetarians and near-vegetarians in the centenarian population. Perhaps a plant-based paleo approach would be best for longevity to avoid the complications associated with grain and legume intake we see in typical vegetarian/plant-based diets.