This paper describes an evaluation of the consequences of a restricted diet on aging markers and life span of Labrador retriever dogs. Forty-eight dogs were studied, being placed into pairs. One of each pair was fed 25% less food than its partner from eight weeks of age until it died. During this period, until twelve years of age, each dog was assessed annually for serum biochemistry, body condition and body composition, age at onset of chronic disease and median and maximum life spans. Results showed benefits of restricted feeding not only on reduced illness and onset of disease but also on extended lifespan.