Labrador Retrievers are ranked as the most popular dog breed in the U.S. by the American Kennel Club (AKC), and the breed has held this title for at least the past three years.

Charlotte, the two-year-old Black Lab keeping my toes warm at this moment, agrees that she is extremely popular and also pretty hungry, as usual. So why are Labs so popular — and why are they are always so hungry?

yellow labrador retriever

Source: skeeze / Pixabay

The breed was developed from the St. John’s water dog in and around the Newfoundland and Labrador coasts of eastern Canada in the early 1800’s. Once they moved into England and the Americas, the breed became known as the Labrador Retriever because they were already well-known as “retrievers” from the sea of Labrador.

The Labrador breed has been described by the AKC as “kind, pleasant, outgoing and tractable” in nature. These dogs have been bred for hundreds of generations for their willingness to remain quietly in a duck blind or wait patiently on the shore while the boss awaits the perfect shot and downs a waterbird. The Labrador watches the bird hit the water and springs into action, using his superior sense of smell to locate the floating prey and bring it back to the waiting hunter.

black lab swim

Source: Lucas Laronga / Flickr

The dog and the hunter are a team, and the dog well knows his job is to jump into the freezing water and fetch the hunters’ dinner. This is the life of a working dog, and they have been selected for these traits over the past 200 years.

Related: Here Are 5 Essential Items You Need To Go Camping With Your Dog

And many of the same traits that make a happy, congenial, well-mannered hunting dog also contribute to the affability of a great family dog. Labradors thrive on love and companionship. Their family is their “hunting partner” and a team spirit prevails.

chocolate labrador puppy

Source: R0Ng / Flickr

Labs are masters of obsessive behavior and unending entertainment when it comes to retrieving, swimming, boating, hiking, sleeping, and eating. Once you get them started, it’s difficult to get them stopped. Many dogs demonstrate these behaviors, but Labs seem to do it with more gusto than most breeds.

Speaking of eating with gusto: Labs have been reported to have the highest obesity prevalence of all dog breeds. Along the same lines, Labs have been shown to be more food-motivated than other breeds. Why?

black lab treat

Source: scott1346 / Flickr

When it comes to obsessive eating, they literally can’t help themselves.  A recent study provides a molecular explanation for what Lab breeders and owners have known for a very long time: that Labs love to eat.

Related: Your Dog’s Food May Be More Important Than You Think. Here’s Why.

As it turns out, the gene that keeps appetite and energy in check (the so-called POMC gene) is mutated in Labs, thus leaving the dogs unable to tell when they have had enough to eat and unable to sense high levels of body fat.

Thus, they eat and eat and eat and never have a sense of satiety because those genetic mechanisms are disrupted and not working properly. This mutation is not present in any other breed of dog except the closely-related flat-coat retriever.

black lab

Image courtesy of Max Arens

The good news from all this is that we now know why Labs will work for food! Some trainers think that Labs are the most trainable of all dog breeds, and this new information may tell us why this is true. No matter how much they eat, Labs with the POMC mutation do not ever get a feeling of being full.

Thus they are virtually always ready to “sit” for food, “down-stay” for food, “come” for food, “heel” for food — you get the picture. In a cohort of 81 Labrador assistance dogs who were studied for the POMC mutation, the prevalence of the mutation was about 4-fold higher than in another cohort of 411 pet dogs from the U.K. and U.S. Thus, it appears that breeding of assistance/service dogs has (perhaps unwittingly) selected for mutations in the POMC gene.

black lab service dog

Image courtesy of Max Arens

The trainers of these service dogs depend on the willingness of the dogs to respond to food stimulus over and over again on a daily basis throughout their rigorous training and into their years as service animals. Labradors respond, in spades!

The young, enthusiastic, companionable, tail-wagging, not overweight, treadmill-trained Labrador currently keeping my toes warm is telling me that it’s 4:30 and time for dinner. Charlotte hasn’t retrieved any ducks today, but keeping my toes warm is an important job, too, so she’ll get her dinner — but I won’t be surprised if she asks for more.

Header images: Kevin Rodriguez Ortiz (left) and Art N. (right)