Labradors’ overeating gene may explain human obesity risk, researchers say

LOS ANGELES - Scientists studying Labrador retrievers—a breed known for its insatiable appetite—have discovered a genetic link between obesity in dogs and humans.

The DENND1B gene, previously linked to obesity in people, was found to alter hunger signals in Labradors, making them more prone to overeating. Researchers at the University of Cambridge analyzed the genetics of 250 Labradors and found that dogs carrying this gene variant had about 8% more body fat than those without it.

Dr. Eleanor Raffan, the study’s lead researcher, emphasized that genetic predisposition plays a significant role in weight gain.

"Owners of slim dogs are not morally superior. The same is true of slim people," Raffan said. "If you have a high genetic risk of obesity, then when there’s lots of food available, you’re prone to overeating and gaining weight unless you put a huge effort into not doing so."

How do genetics influence obesity?

By the numbers:

Obesity in dogs and humans is influenced by both genetic and environmental factors. Just as humans with high genetic risk can manage their weight through diet and exercise, the study found that Labrador owners who strictly controlled food intake and activity helped prevent obesity in their dogs—even in genetically predisposed ones.

• 40-60% of pet dogs are overweight or obese, similar to human obesity rates.
• Labradors with the DENND1B gene had 8% more body fat than those without it.
• US obesity rates exceed 42%, according to the Centers for Disease Control and Prevention (CDC).
• Weight-loss drugs like Ozempic and Wegovy target brain pathways that regulate appetite.

Dr. Alyce McClellan, joint first author of the study, noted that while this research helps scientists understand how genes influence eating behavior, it doesn’t immediately translate to weight-loss drugs.

FILE - A black Labrador retriever eagerly eyes a meal, illustrating the breed's well-known appetite. ((Photo by Michael Albans/NY Daily News Archive via Getty Images)

"These genes are not immediately obvious targets for weight-loss drugs, because they control other key biological processes in the body that should not be interfered with," McClellan explained.

However, the study reinforces the importance of fundamental brain pathways in controlling appetite and body weight.

What does this mean for future obesity research?

What's next:

The discovery strengthens the case that obesity is not simply a matter of willpower, but a complex interaction between genetics and environment.

While drugs like Ozempic and Wegovy target hormones that regulate appetite, the study suggests that brain pathways controlling hunger signals may hold additional insights into why some people are more prone to weight gain.

For pet owners, researchers recommend strategies to manage a dog’s food intake, including puzzle feeders and scattering food to slow eating and increase mental stimulation.

"Studying the dogs meant we had reason to focus on this particular gene, which has led to a big advance in understanding how our own brain controls our eating behavior and energy use," Raffan said.

As scientists continue to explore genetic influences on obesity, this study highlights that solutions may not be one-size-fits-all, but tailored to individual biology—whether human or canine.