An estimated 59 percent of American pets are overweight or obese. Many factors contribute to this. The role of food and treats in the human-animal bond, the sedentary lifestyles of owners and pets, inadequate and/or incorrect nutritional information from veterinarians, and a lack of recognition of health and disease and risk factors for even small amounts of excess body fat are all major contributing factors. Of equal importance are the practices by commercial pet food companies with regards to feeding guidelines and lack of nutritional label transparency.
Due to the individual variations in metabolism, any feeding instructions should be viewed as starting or reference points that are subject to change. Weight loss or gain at any level of feeding should signal the need to increase or decrease the amount of food. Medical status, life stage, and activity changes should also signal the need to change feeding practices. But in general, feeding instructions on commercial pet food is too generous and calorie recommendations are typically high. This is in part due to the formulation guidelines of the National Research Council (NRC) and the Association of American Feed Control Officials (AAFCO).
In their recommendations the NRC and AAFCO specify the amount of all essential daily nutrients for dogs and cats that is required in each 1,000 calories of food. These guidelines assume calorie consumption based on laboratory dogs (generally sexually intact) or active pet dogs and lean cats (also usually intact). In other words, these guidelines are targeted at the nutrition necessary for animals with greater caloric needs than the normal, neutered, less active pet. As a result, feeding charts on pet food tend to encourage overfeeding.
I did a quick comparison of four dog foods: two popular economy brands and two premium brands. The NRC equation for less active dogs recommends a 50 lb dog get 1,000 calories daily. Using the feeding instructions of the four brands, my 50 lb. dog would receive, on average, 140-170 extra calories per day. For one year, that is 51,100-62,050 extra calories. Assuming that 3,500 calories equals one pound of body weight (commonly used in human nutrition), then my imaginary dog would gain an extra 14 ½- 17 ¾ lbs. every year.
Pet food labels are not required to disclose the calorie density of their product. AAFCO has recently announced that starting in 2015 this information will be mandatory on pet food labels. What form that information will take is not yet clear. Will it be easy to read, calories per cup or can, or more complicated calories per kilogram of food? If the latter is the case, it would mean owners would have to mathematically calculate the calories per cup or can after weighing a cup or can of food on a kitchen scale. I am pessimistic enough to think it will be the more complicated. Why is calorie information important?
Commercial pet food does not have universal calorie counts. Every food is different. The calorie counts in the four foods in my above comparison ranged from a low 335 calories per cup to a high 531 calories per cup. If you were feeding the low calorie food and then switched to the higher calorie food and fed the same amount (this is what most pet owners do!) your dog would be getting 196 extra calories per cup of food.
Commercial pet food feeding instructions must be more precise, with 5 lb range categories rather than 10-25 lb ranges. Multiple feeding charts for appropriate lifestyle and life-stage should also be available on the label. This will be tough for small cans; they may need attached feeding instructions. Labeling with smart phone readable codes is an easy solution for all labels.
Calorie counts need to be presented in the easiest to understand format so owners and veterinarians know exactly how many calories pets are being fed. Ideally, the calorie contribution of protein, fat, and carbohydrate should also be indicated in the same format used on human food labels.
This won’t solve the entire problem, but it sure would make it easier to develop programs that address the other major causes of pet obesity.
Dr. Ken Tudor