Many dogs' owners don't know proper food portion

Preeti N. Malani, M.D., is a professor of medicine in the University of Michigan Medical School's Division of Infectious Diseases and an associate editor of the Journal of the American Medical Association. She wrote this for "The Public's Health" blog, www.philly.com/publichealth.

Dogs are an integral part of the American family. Our dogs attend day care, enjoy visits to the spa, and accompany their families on vacation - sometimes staying in pet-friendly hotels that serve gourmet dog food. Pooches can have dedicated electronic devices; a sizable number have accounts on social media.

Fittingly, the health of American dogs mirrors that of humans when it comes to their waistlines. Much like the better-known epidemic, the number of overweight pets is rising.

Last year, the American Association for Animal Hospitals published guidelines for weight management of pets, a compilation of evidence on feeding and exercise along with practical advice for veterinarians. Deborah Linder, DVM, chairwoman of the guidelines panel and a veterinary nutritionist at Tufts University, estimates that more than half of dogs in the United States are overweight or obese.

"Just like people, some dogs eat to live and others live to eat," Linder says. But their owners are even bigger contributors.

"Many pet owners have no idea how many calories a dog should get," Linder says. "They don't have a good understanding of how much food their dog really needs."

Linder says the major culprit usually is not a dog's regular meals, but the treats that can come throughout the day.

Still, successful portion control requires accurate weighing and measuring of food: "One cup is 8 ounces, not a Big Gulp," she notes.

Exercise is also important, but Linder says the real battle is shifting the entire culture of how we feed dogs. One of the major barriers to weight loss involves owners who wrongly equate restricting a dog's calories to decreasing her quality of life.

"Weight loss is not emotionally hurtful to pets

and does not cause them pain" she says. In fact, overweight animals have a decreased quality of life and are more likely to be in pain from arthritis and other ailments. Several studies demonstrate improvement in pain, anxiety, and general well-being after successful weight loss in dogs.

Here's something else to consider: Dogs develop stronger bonds with the people who walk them than with those who provide food, Linder says, an observation that she attributes to time. It simply takes longer to go on a walk.

Doggy day care and dog-walking services can help provide consistent activity, but Linder says they are not the only options.

"Some of us have a sedentary job, but we can still go for a walk at the end of the day."