There was an interesting article on The State of Pet Health 2012 published recently by Banfield Pet Hospital.
They state that chronic diseases have been on the increase in the past 5 years. Obesity and overweight by 37% in dogs and 90% in cats. 1 in 5 dogs and cats are overweight. They also stressed the importance of early detection and working in partnership with your veterinarian. For more information, check out their article: