In this article
Rustle a crisp packet anywhere in the house and a Labrador will be at your knee before it is open. Breakfast was an hour ago, but the eyes say they have not eaten in days. Most Labrador owners know that look, and plenty have been told, kindly or otherwise, that they must be a soft touch.
Research from the University of Cambridge suggests the dog is not always putting it on. Scientists there have found gene changes that make some Labradors hungrier than others, and one that also seems to lower the energy a dog burns at rest. Here is what they found, why it lets you off the hook for the hunger (if not the portions), and how to live with a food-mad dog.
A gene that turns up the appetite
Labradors already had the reputation and the figures to match: of all breeds with published data, they had the highest recorded obesity rates, and they had been shown to be more food-motivated than other breeds1. In 2016 a Cambridge team, with vet Dr Eleanor Raffan as lead author, looked for a reason in their genes1.
They started with 15 obese and 18 lean Labradors, reading three genes from a brain pathway that, in people and mice, helps control how much is eaten1. One difference stood out: a small deletion, 14 letters of genetic code missing, in a gene called POMC1. POMC is the recipe for a protein that is cut into smaller messengers, and the deletion disrupts two of them, beta-MSH and beta-endorphin, both involved in balancing food and energy1.
What the 2016 study found
Carriers also had more body fat, and their owners rated them as more interested in food1. A team in Poland later tested 272 dogs from four breeds prone to weight gain, found the deletion only in the Labradors, and confirmed its link with body weight, though not with body condition, which they also scored5.
Why assistance dogs carry it more often
The most surprising figure came from 81 Labradors kept for breeding by an assistance dog programme: about three in four carried the deletion, 64% with one copy and 12% with two1. The researchers suggest a neat reason. Assistance dogs are chosen mainly for temperament and trainability, and puppy training relies heavily on food rewards, so dogs that will do anything for a biscuit may be likelier to be picked1.
Hungrier between meals, thriftier at rest
In 2024 the Cambridge team tested what the deletion does to a dog. They gave 36 Labradors a measured meal, then three hours later showed each dog a sausage and sealed it in a plastic box with holes in it2.
Dogs with the deletion spent longer pawing, biting and looking at the box, and less time resting or exploring the room2. The researchers read this as greater hunger, the kind of pull towards food that is likely to drive begging, stealing and foraging at home2.
What they did not find matters too. In a second test, described in the methods as involving 24 Labradors, dogs were offered tinned food every 20 minutes after a night without food. Feeding usually ended when they left some uneaten or brought it back up; a few dogs stopped at a safety limit or the owner's request. More than half the non-carriers brought food back up2.
Dogs with one copy of the deletion did not eat significantly more than the others, which suggests their sense of fullness works normally2. Even dogs without the deletion ate, on average, about twice their daily energy needs in that one long meal, which will surprise no Labrador owner2.
A third experiment explains why the weight piles on. In a small study of 19 lean flat-coated retrievers, those with two copies of the deletion burned about 25% less energy at rest than dogs without it, allowing for body weight2. That, the authors say, is enough to make a real dent in how much food a dog needs to stay a healthy weight2.
Put together, a dog with the deletion wants food more and needs less of it. Keeping such a dog slim means feeding less than a typical dog would need, the researchers wrote, which is hard with a dog this keen on food. Yet the many slim carriers in their study show it can be done2.
More genes, and a link to people
POMC is not the whole story. In 2025 the team scanned the DNA of 241 Labradors for anything linked to body condition score, a nine-point scale for judging body fat by look and feel3. The strongest signal sat within a gene called DENND1B, and each copy of the higher-risk version came with about 7% more body fat3.
The same gene turns up in people. In genetic data from more than 800,000 people, variation in the matching stretch of human DNA was linked to body mass index, and lab work suggests the gene tunes MC4R, a brain receptor that is a critical controller of energy balance3.
The scan also found four more genes with smaller effects, and no single gene decided whether a dog was prone to obesity: the combined effect of many variants did4. Chocolate Labradors and dogs bred for assistance work, both already known to be more prone to weight gain, tended to carry a higher genetic risk3.
Your part still counts
The team gave dogs a genetic risk score and asked owners, through a questionnaire, how tightly they managed food and exercise. Among high-risk dogs, stricter management went with lower body condition scores, while low-risk dogs tended to stay a healthy weight whatever their owners did3.
High-risk dogs were prone to obesity when they got little exercise and food was easy to come by, whether that meant being offered human food or not having their portions limited3. Owners who strictly controlled diet and exercise kept even these dogs from becoming obese, though it took much more attention and effort4.
Hunger is not a failing, yours or theirs
All of this should take some of the guilt out of the begging. A Labrador who acts as if every meal is the last is not proof of a weak-willed owner, and a slim Labrador is not proof of a saintly one.
Studying the dogs showed us something really powerful: owners of slim dogs are not morally superior4.
She went on to say that the same is true of slim people: with a high genetic risk and lots of food around, you are prone to overeating and gaining weight unless you put a huge effort into not doing so4. For a dog, that effort falls to whoever holds the food. The encouraging news is that it works.
Living with a food-mad Labrador
Keeping a hungry dog slim is worth the trouble: vets estimate that nearly half of UK dogs are overweight, and extra weight is linked to arthritis, diabetes and a shorter life6. Whatever your dog's genes, the plan is the same, and if they need to lose weight, start with your vet practice. Plans should suit the individual dog, and many practices run weight clinics6.
| Try this | Why it helps |
|---|---|
| Measure every meal | Ask your vet or vet nurse how much to feed, then measure it out carefully6 |
| Make meals last | Puzzle feeders or food scattered on the lawn spread the ration out and keep a hungry dog busy4 |
| Budget the treats | Keep treats to 10% of the daily allowance at most, cut meals to match, and reward with play too7 |
| Agree a house rule | High-risk dogs fared worse where owners offered human food, so agree that nobody shares3 |
| Ask about the food | A food chosen with your vet can help a dog lose weight without getting too hungry4, 6 |
| Weigh your dog often | Regular weigh-ins make weight loss more successful; many practices have scales you can use6 |
When the hunger is new
Genes are not the only thing that can sharpen an appetite. Neutering brings hormonal changes that may increase appetite and slow metabolism, so a neutered dog is likely to need fewer calories6. Some medicines, such as steroids, can lead to weight gain, particularly if they affect appetite, so tell your vet if your dog's hunger changed after starting one6.
A sudden change in appetite deserves a vet's attention. Increased hunger, along with drinking more, weeing more, weight loss or low energy, can be among the first signs of diabetes, and PDSA advises contacting your vet if you notice them8. Much less often than diet and exercise, Cushing's disease or an underactive thyroid can cause weight gain, and a dog with either is likely to show other signs too, such as coat changes, low energy or increased thirst6.
The begging may never stop entirely; for plenty of Labradors it comes with the territory. But a dog who hunts the lawn for breakfast, earns a game as often as a biscuit and steps on the vet's scales at a healthy weight is a contented Labrador, however tragic the face at teatime.
Sources and further reading8 sources
The small numbers in the article link to the source behind each fact. Sources open on their own websites.
- A Deletion in the Canine POMC Gene Is Associated with Weight and Appetite in Obesity-Prone Labrador Retriever Dogs
- Low resting metabolic rate and increased hunger due to β-MSH and β-endorphin deletion in a canine model
- Canine genome-wide association study identifies DENND1B as an obesity gene in dogs and humans
- Scientists identify genes that make humans and Labradors more likely to become obese
- Confirmation that a deletion in the POMC gene is associated with body weight of Labrador Retriever dogs
- Obesity in dogs
- How to treat your dog
- Diabetes in dogs