We are all familiar with the obesity epidemic facing American men and women today. But have you heard about its threat to man’s best friend? More than 50 percent of American dogs are obese, according to Wall Street Journal editor Wendy Bounds. Today, our dogs are suffering from the same threats as our community — overweight and inactive, pets are developing weight-related illnesses like diabetes, arthritis, high blood pressure and kidney disease.

As they say: like owner, like dog. The reason for obesity in dogs mirrors that of obesity in humans: Increased caloric intake and consumption of unhealthy foods are leading dogs around the nation to get heavier and heavier. For both mammals’ problem, the food industry plays a large role. Dog foods manufactured in America often cater their nutritional content to that of un-spayed or un-neutered youth. The directions and ingredients are both too hearty for dogs after they pass this puppy stage and have slower metabolisms.

But manufactured dog food is not the only culprit. The habit of feeding pets table scraps is another major contributor to the health of man’s best friend. Pet owners easily underestimate the magnitude of food they feed their animal. Did you know that a cat drinking just one cup of milk is analogous to a human eating four and a half hamburgers? This translation is equally astonishing in terms of weight as well: A 14-pound cat is equal to a 237-pound man, and a Yorkie dog of 12 pounds is about equivalent to a woman weighing 218 pounds.

These facts expose a fundamental difference between obesity in pets and that in humans: Animal obesity is more extreme and less frequently self-inflicted. Today, many people complain of the “obesogenic” environment as increasing their propensity to overeat unhealthy foods. But pets have even more grounds to blame their environment and its pressures for eating habits. Some might even go so far as to say the irresponsibility of overfeeding one’s pet is a form of animal cruelty. Dogs that are overweight can suffer crippling joint pain. Even more poignant, letting one’s dog become overweight is like decreasing its lifespan by two years.

Owners have personal incentives to properly feed their dogs as well. Lifetime diseases cost thousands of dollars in veterinary and medical costs. Insulin for diabetes and pain medications for arthritis together can add up to over $1,000 in medical bills.

In light of this serious predicament to both dog and master, a number of support and education programs have been developed. The Association for Pet Obesity Prevention (APOP), the Science Diet Slim Down food program and Purina’s “Project: Pet Slim Down” are three examples of resources available to pet owners. In addition, just like in the human world, businesses have taken advantage of the doggy diet trend, developing lucrative (and adorable!) products such as doggy treadmills and self-regulating feeders.

Unfortunately, despite these efforts, the rates of pet obesity continue to increase. Just as humans need education about how to maintain their personal well-being and healthy weight, veterinarians and programs must teach about what constitutes a good-sized dog, says APOP founder Dr. Ernier Ward. National Pet Obesity Awareness Day — October 13, 2011 — represents a landmark on this path toward prevention.

At the foundation of this problem lies the question of how much we love our pets. Most Yalies respect themselves and generally treat their own “bodies like a temple.” It is harder to mind your pet’s body, until you realize that it is a temple that relies equally on your own care and concern. Since the physical state of your dogs and other pets depends so much on you, it is important to be astute and attentive. You will glean benefits too; when a dog is active, its owner is active, and an owner conscious about portion size for her pet can learn personal habits as well. It all comes down to kinship: If dogs really are “man’s best friend,” then we cannot let them be unhealthy.