Labradors are famous for two things: their undying devotion and their ability to inhale an entire meal in 0.3 seconds. Turns out, there’s a genetic reason for that second one. Researchers studying British Labs have pinpointed multiple genes linked to obesity—genes that also show up in humans.
The main suspect? A gene called DENND1B, which sounds like a robot assassin but actually messes with the brain’s ability to regulate hunger. It hijacks the leptin melanocortin pathway, a neural circuit responsible for balancing energy intake. In simpler terms: this gene might be whispering, “Eat that third slice of cake, you know you want to.”
But DENND1B isn’t working alone. There’s an entire squad of genes, four to be exact, that also contribute to canine (and human) weight gain. Their influence is less dramatic, but their presence makes it clear—biology isn’t playing fair when it comes to staying slim.
The bad news? There’s no magic pill to shut these genes down. They’re tangled up with other critical processes that scientists aren’t keen on messing with. “We can’t just turn them off without causing collateral damage,” says Alyce McClellan from the University of Cambridge.
And these genes don’t just make Labradors (or people) more likely to gain weight—they make them obsessed with food. Researchers observed that Labs with these genetic markers were more likely to beg, steal, and scheme for extra snacks. They weren’t just eating more; they were laser-focused on their next meal, like tiny furry masterminds plotting a kitchen heist.
Humans with the same genetic markers show similar tendencies. Higher genetic risk correlates with a stronger appetite, an inconvenient reality in a world where food is designed to be irresistible. And while strict diet and exercise can override the genetic programming, it takes a near-heroic level of self-control.
This wasn’t just a theory—dog owners who meticulously controlled their pets’ food intake and exercise managed to keep their Labs slim, even the genetically predisposed ones. The takeaway? Willpower isn’t a myth, but it’s a much heavier lift for those wired to crave food like it’s oxygen.
Dr. Eleanor Raffan, who led the study, put it bluntly: “Owners of thin dogs aren’t morally superior.” The same applies to people. If genetics are stacked against you, resisting the siren call of snacks requires constant vigilance.
And unlike dogs, humans don’t have an owner measuring out their meals and forcing them on daily walks. Maybe that’s for the best—until someone develops an intelligent AI that locks the fridge when you’ve exceeded your calorie limit. A dystopian nightmare? Maybe. But given what we now know about genetics… it might be the only way to win.
Five Fast Facts
- DENND1B has also been linked to asthma, making it one of the few genes that can both make you overeat and struggle to breathe at the same time.
- Labradors were originally bred as fishing dogs in Newfoundland—meaning their love of food probably helped them survive harsh conditions.
- Leptin, the hormone regulated by the appetite-controlling pathway, was only discovered in 1994, proving that science took its time figuring out why people love snacks.
- The average Labrador can eat up to 60% more calories per day than a similarly sized dog without gaining weight—until DENND1B gets involved.
- Cambridge, where this study took place, is the same university that helped discover the structure of DNA—so clearly, meddling with genetics is a local specialty.