Dogs are an integral part of the American family.   Our dogs attend daycare, 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.  Just like their human counterparts, excess weight can have serious health implications for our canine companions.

Also just like humans, there is plenty that you can do about it. (Keep reading!)

Last year, the American Association for Animal Hospitals published guidelines for weight management of pets, a compilation of current evidence on feeding and exercise along with practical advice for veterinarians.  Deborah Linder, DVM, chair of the guidelines panel and a veterinary nutritionist at Tufts University, estimates that more than 50% of dogs in the United States are overweight or obese.

Linder explains that the condition—again, like that for humans—involves multiple factors, and the reasons differ for each animal.  Genetics plays a significant role: some breeds are  more prone to obesity or having bigger appetites.  "Just like people, some dogs eat to live and others live to eat," says Linder.  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."

Similar to humans, obesity affects every organ system in dogs.  With their shorter life spans, however, even a few extra pounds can have a negative impact on health.  According to Linder, dogs that maintain an ideal body weight live an average of two years longer than dogs that are overweight.

"People develop strong psychological bonds with their pets which is fantastic, but the way that food gets incorporated into that relationship is often unhealthy," Linder summarizes.  As a result, "…changing a pet's diet means changing that bond and changing how the owner interacts with their animal."  In her veterinary practice, Linder acknowledges this vital connection but also works around it to formulate a realistic weight-loss plan that preserves and even strengthens the relationship:  "If you normally bond with your pet by giving him a treat, we work to identify a substitute."

According to Linder, a dog's weight issues are almost always related to human factors.  Owners often say: "I can't resist a cookie and I can't resist giving him a cookie."  In fact, a pet's primary source of food is rarely the culprit.  Rather, treats are the problem—cookies, people food, bones, rawhide.  A marrow containing bone can have more than 1,000 calories.  While providing treats is a central component of many pet owners' relationships with their dogs, Linder recommends that treats make up no more than 10% of daily calories.

Although the pet food market is burgeoning, nutrition labels lag.  Even when it is available, nutritional information generally is presented by weight, not volume.  When choosing a weight-loss food, Linder says, nutrition density is important.  "You need to cut calories but not nutrients," she explains, noting that optimal nutrition is especially important for younger dogs that are still growing.

Linder also instructs dog owners to carefully quantify what their pets are fed.  "Free feeding doesn't work.  Those animals will gain weight," she says.  Successful portion control requires accurate weighing and measuring of food:  "One cup is 8 ounces, not a Big Gulp."

When a dog won't accept a new diet, Linder suggests trying different textures and moisture content (wet versus dry food).  Automatic feeders can also be helpful, especially for dogs that are alone for long periods.  There are even systems to deliver a dog treat virtually using a smartphone or tablet. Some of them can do a two-way video chat.

The placement of food can help to encourage exercise, too.  Rather than allowing your  dog to eat all of her food quickly, for example, try putting it in different areas of the house,  requiring a room-to-room walk in search of food.  "Pets need to work their minds and their bodies," says Linder.  She recommends a variety of interactive feeding toys that help engage pets cognitively.  For example, a small treat can be placed inside a contraption that requires a dog to maneuver a series of slats to get to the food.

For Linder, the battle goes beyond diet and exercise and is instead about shifting the entire culture of how we feed dogs.  "We need to break the myth that an overweight pet is a happy pet," she laments.  One of the major barriers to weight loss involves owners that wrongly equate restricting a dog's calories to decreasing her quality of life.  This simply isn't true, Linder says, and there is ample evidence to suggest the opposite.  "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.

Linder's best advice for helping a dog maintain proper weight is simple: start early.  She says that the first puppy visit is the ideal time to discuss why a healthy weight is important.  In addition to feeding basics and the importance of physical activity, veterinarians will explain how to judge "body condition score," a clinical measure that determines whether or not a pet is at a healthy weight.  This involves a dog's ribs.  Linder says they should feel similar to the back of your hands:  "In pets, you can't tell [whether or not they are overweight] just by looking.  Fur adds a different element."  Health-related changes throughout a dog's life also impact nutritional needs.  Calorie requirements decrease by about one third after spaying or neutering due to related hormonal changes, but appetite may actually increase.

In both humans and animals, successful weight loss requires a combination of diet and exercise.  A challenge is that dogs develop stronger bonds with the people who walk them than with those that provide food, Linder says, an observation that she attributes to time; it simply takes longer to go on a walk.  Doggie daycare 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."

Preeti N. Malani, a medical doctor and master of science in journalism, 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.

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