[anonymously]

I have found some helpful information at this site: http://skeptvet.com/Blog/category/nutrition/

Also, I believe that genetics plays a major role in our longevity, animals too.

A homemade diet, some tips in general guidelines you may find helpful:
http://www.homeovet.net/dynamic/php/downloads/dog-c8470f2c75dbe4b683205c3919ee2310/dog_diet_complete.pdf