I think a lot of a dog's longevity is genetics, but I do like to feed my animals something with less crap in it. I assume the raw food diets are probably best for their health but I just don't want to deal with the preparation and clean up and potential for germs. I like the convenience of bagged food. For those with a Costco nearby, they seem to have some healthier, yet still convenient options now. My dog passed years ago so I don't have experience with their food but this one seems decent based on the ingredients.
Costco Nature's Domain Dog Food 
