Some Labradors Are 'Hungry All the Time' for a Good Reason, Scientists Warn

If your fluffy friend seems to be constantly ravenous, it might come down to their genes.

A quarter of all Labrador retriever dogs have a specific genetic mutation that causes them to feel hungry all the time but also burn fewer calories, according to a study published in the journal Science Advances.

This genetic mutation is in a gene called POMC, which plays a role in appetite and energy metabolism. Therefore, owners of dogs with a mutation in POMC may need to pay closer attention to their dogs' diets.

The paper reveals that 25 percent of Labradors and 66 percent of all flat-coated retriever dogs have the POMC mutation, meaning that they have an increased risk of obesity due to their higher appetite than other dogs. It also found that the dogs with the genetic mutation felt hungrier in between meals and used about a quarter fewer calories when at rest than dogs without the mutation. This means that they don't need to consume as many calories to just exist.

"We found that a mutation in the POMC gene seems to make dogs hungrier. Affected dogs tend to overeat because they get hungry between meals more quickly than dogs without the mutation," study author Eleanor Raffan, a neuroscience researcher at the University of Cambridge said in a statement.

"All owners of Labradors and flatcoated retrievers need to watch what they're feeding these highly food-motivated dogs, to keep them a healthy weight. But dogs with this genetic mutation face a double whammy: they not only want to eat more, but also need fewer calories because they're not burning them off as fast."

The paper describes how they tested 87 adult pet Labradors using a game called "Sausage in the Box," which involved placing a sausage in a box with a clear lid that had been perforated slightly, meaning that the dogs could smell the food but not eat it.

They found that despite all the dogs having been fed the same amount three hours prior, dogs with the POMC mutation tried significantly harder to get the sausage from the box than those without the mutation, indicating that they were feeling hunger more strongly.

Therefore, it might not necessarily be the dog's or the owner's fault if the dog gains weight despite eating what would usually be considered a healthy amount of food.

"People are often rude about the owners of fat dogs, blaming them for not properly managing their dogs' diet and exercise. But we've shown that Labradors with this genetic mutation are looking for food all the time, trying to increase their energy intake. It's very difficult to keep these dogs slim, but it can be done," Raffan said.

Interestingly, the POMC gene affected similar brain pathways in humans as it does in dogs. These findings in the Labradors are consistent with previous research into humans with mutations in POMC, who often become obese at a young age.

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