Why Do Dogs Eat Poop? Science May Finally Have the Answer

The initial shock of seeing your dog eat poop for the first time is enough to make you look back and wonder where you went wrong as a pet parent. “Surely, my sweet boy would never do such a thing!” you tell yourself, or you’ll say, “He must’ve fallen in with the bad crowd at obedience school.” And if you happen to be out and around others when it happens, the resulting embarrassment can make you to want to curl up and die.

But science may finally be able to provide you a little comfort in your time of shame, as well as a logical reason behind your dog’s bizarre behavior.

Why Do They Do It?

First thing’s first: dogs eat poop. It’s certainly weird to us, but it’s pretty normal for them. The act of eating feces, otherwise known as coprophagia, is nothing new among dogs.

It seems there is no end to the speculation and hypotheses put forth by scientists, behaviorists, and other experts in attempts to answer the question of why dogs eat poop. Some of the more popular explanations range from diet deficiencies to anxiety, and from instinct to learned behavior.

In two recent surveys performed by University of California at Davis personnel, in which close to 3,000 dog owners participated, researchers attempted to find a link between coprophagia and dogs, and their data provided new insight into the unpleasant behavior.

Of owners polled, the vast majority of their dogs preferred new poo—over 80 percent of the dogs observed went for droppings that were one to two days old. This behavior in particular led the researchers to hypothesize that the rationale behind the behavior is hard-wired into doggy behavior, dating even farther back than dogs themselves.

The Lupine Connection

As social creatures, wolves tend to live closely with other wolves in packs. They howl together, hunt together, and often help to take care of each other’s pups. But, living so closely to others can have its disadvantages as well—if a wolf gets sick, the close proximity of pack members makes it easier for that disease to spread.

But, it seems that over thousands of years, wolves have developed a sort of protective mechanism to keep the spread of illness at bay. That’s right, I’m talking about eating poop. As crazy (and disgusting) as it sounds, when a wolf became ill, it often wouldn’t have the energy to do its business far away from the den, so a healthy wolf would come along and take care of the problem by—you guessed it—wolfing it down. Because the parasite eggs contained in the sick wolf’s feces required days to hatch, a healthy wolf could consume those droppings and safely expel them away from the living area before the eggs had a chance to hatch and put the rest of the pack at risk.

DVM Benjamin Hart, a professor at the UC Davis School of Veterinary Medicine, was one of the leading researchers involved in the study. He suggests that the data showing a distinct correlation between the age of the feces and the number of dogs that ingest it (again, 80 percent of the poop-eating dogs drew the line at stool older than two days), is likely an instinctual remnant from the dogs’ genetic connection to wolves.  So, even though the behavior no longer has a purpose in the life of a modern-day domesticated dog, it still persists to this day because it is an inherited, instinctual trait.

Does Science Have an Answer?

So, if you’ve come here looking for a solution to your dog’s caca cravings, sadly, there isn’t much that can be done. Given that the action seems to be hardwired into the dogs themselves, it’s not an easy habit to break. The researchers found that owners’ attempts to stop the behavior through commands, hot pepper products (on the droppings), and the use of 11 over-the-counter products all fell flat.

But, as desperate as the situation sounds, there may still be a light at the end of the tunnel for dog owners. “We’re going to be looking at some clinical trials on treatments that are different enough that they’ll stand a chance of working,” Hart told the Washington Post. “We’re going to put our heads to this.” Here’s hoping Dr. Hart and his team succeed were all the rest have failed, and the shock and betrayal of a poop-eating pup will just be a thing of the past.