ScienceDaily (Mar. 19, 2011) — The nutritional content of dog foods marketed for old dogs varies as widely as owner's perceptions about them, according to a study published this month by veterinary nutritionists at the Cummings School of Veterinary Medicine at Tufts University.

Although it is commonly accepted that nutritional needs -- both for humans and pets -- change with aging, the Association of American Feed Control Officials (AAFCO) and National Research Council have not set official dietary requirements for aging dogs. As such, foods marketed for "longevity" and "maturity" or "senior," "old" or "mature" dogs do not have to adhere to a standard nutrition profile beyond the AAFCO nutrient profile minimums for adult dogs.

In the study, Tufts researchers polled more than 1,300 people online about their perceptions about these foods. Their responses were correlated with the actual nutritional content of nearly 40 commercially available "senior" dog foods, and the study, led by resident Dana Hutchinson, DVM and Lisa Freeman, DVM, PhD, were published in the latest issue of the International Journal for Applied Research in Veterinary Medicine.