Posted: January 27, 2010, 2 a.m. EST
A recent evaluation of calorie density and feeding directions for commercial weight-control dog foods reveals wide variations, which may confuse owners of obese pets, according to the study by the Cummings School of Veterinary Medicine at Tufts University.
Pet owners buying weight-loss foods for their pets are faced with a confusing two-fold variation in calorie density and recommended intake, and wide range in the cost of low-calorie foods, according to Lisa Freeman, D.V.M., Ph.D., and diplomate of the American College of Veterinary Nutrition. Freeman is the study’s co-author along with Deborah Linder, D.V.M., a 2010 Cummings School graduate. In addition, the way by which feeding directions for normal-weight animals are determined varies among manufacturers.
The study appears this month in the Journal of the American Veterinary Medical Association. Linder and Freeman studied 44 canine diets.
Among the findings is that dry dog foods range in calorie density from 217 to 440 kilocalories per cup (kcal/cup) and a recommended intake that ranged from 0.73 to 1.47 times the dog’s resting energy requirement. The diets also varied in price – from 4 cents to more than $1.10 per kilocalorie.
Federal guidelines require pet foods labeled “lite,” “light,” “low calorie,” “less calorie,” or “low calorie” to provide the caloric content. Foods designated as such must also adhere to a maximum kilocalorie per kilogram restriction.
However, Freeman said that more than half of the pet foods evaluated exceeded this maximum. Foods without these designations are allowed, but not required, to provide the caloric content on the label.
“There is so much information – and misinformation – about pet foods, it’s understandable that people are confused about what to feed their dogs and cats,” said. Freeman, professor of nutrition at Tufts University’s Cummings School of Veterinary Medicine. “To counteract these myths, people are accustomed to turning to the labels on food – but, as this study shows, packaging might not always be a reliable source of information.”
Another key issue the study identifies involves the high variability in feeding recommendations for weight loss based on the labels that were evaluated. For most of the diets, pets would not lose weight or would gain weight if owners followed the labels’ feeding directions and didn’t adjust according to their pet’s individual calorie requirements, according to the study.
Obesity in pets is linked to numerous diseases, including pancreatitis, osteoarthritis, dermatologic disease and diabetes – and may contribute to a shorter lifespan, according to earlier published studies.