Obesity is one of the most common health concerns in dogs today. In fact, recent estimates suggest that a whopping 59% of dogs worldwide are overweight or obese. While nutrition and activity level play an important role in weight management, research increasingly shows that genetics can influence how a dog regulates appetite, responds to food, and maintains a healthy weight.
Understanding canine genetics
Every dog is shaped by a unique genetic blueprint. DNA contains genes that act as instructions for how the body develops and functions—from visible traits like ear shape and coat type to behind-the-scenes processes like metabolism, hormone signaling, and appetite regulation. For a deeper dive on how DNA is structured and how genes determine traits, check out this blog post.
Advances in canine genetics have made it possible to study how specific genetic variants contribute to health outcomes. Large datasets that combine genetic testing with veterinary records, like those used by Mars Petcare research teams, have helped scientists identify links between certain genes and conditions like obesity, joint disease, and metabolic disorders.
Genetic factors contributing to obesity in dogs
Obesity in dogs is considered a complex, multifactorial condition. That means it is shaped by both genetic predisposition and environmental factors. On the biological side, evidence points to genetics affecting things like appetite regulation and energy balance, rather than a single “obesity gene.” Let’s take a look at some examples.
Appetite, satiety signaling, and energy balance
Does your pup always seem hungry and would do anything for food? Genes involved in hunger signaling can influence how motivated a dog is by food. Variants in the POMC gene are associated with increased food-seeking behavior and reduced satiety (feeling full after eating). This genetic mutation, most common in Labrador Retrievers, is included in Wisdom Panel’s Premium dog DNA test.
Other genes in the same metabolic pathway as POMC, including MC4R, have also been studied. Research shows that variants in these genes are associated with differences in body weight in dogs, although their effects are typically more modest and still being investigated.
Additionally, a variant in the DENND1B gene, which controls a pathway in the brain that impacts appetite and energy expenditure, has been linked to increased body fat in Labrador Retrievers. What makes this finding particularly notable is that DENND1B has also been associated with obesity in humans. This overlap suggests that some mechanisms involved in energy balance and weight regulation may be shared across species
The heritability of body weight
Studies have shown that body weight and body condition have a heritable component in dogs. That means some dogs are naturally predisposed to be larger or heavier, but environment—like diet and exercise—still plays a major role.
Genetic links to related health conditions
In addition to genes that directly influence appetite and energy balance, some dogs may have genetic predispositions to health conditions that can affect weight and body condition. For example, certain endocrine disorders, such as hypothyroidism and Cushing’s disease, can influence how the body regulates metabolism, fat distribution, and energy use. These conditions are not primary causes of obesity, but they can contribute to weight gain or make weight management more challenging in affected dogs.
Because these conditions can present with weight gain alongside other clinical signs—such as changes in coat quality, energy levels, or thirst—they are typically diagnosed through veterinary care rather than genetic screening.
Dog breeds most prone to obesity
Breeds commonly associated with increased obesity risk include:
- Labrador Retriever
- Golden Retriever
- Beagle
- Dachshund
- Cocker Spaniel
- Cavalier King Charles Spaniel
- Pug
- Basset Hound
- Boxer
- Rottweiler
We’ve already talked about Labrador Retrievers being the breed most frequently associated with the POMC gene variant. Smaller companion breeds, on the other hand, may be more prone to weight gain due to lower activity levels or overfeeding (extra calories can add up fast for tiny dogs).
The role of environment on obesity risk
A dog’s experiences in their day-to-day life impact their weight. Following are some of the daily factors that can affect their body condition.
Diet: Calorie-dense foods, excessive portion sizes, and frequent treats can contribute to weight gain, particularly in dogs that are genetically predisposed to seek out food.
Exercise: Regular physical activity supports energy balance and helps prevent excess weight gain. Dogs with higher genetic risk may benefit from more structured or consistent exercise routines.
Feeding behaviour and routines: Dogs need to eat every day. But how they eat is important, too. Dogs that are highly food-motivated may benefit from strategies like slow feeder or puzzle toys to help regulate intake.
Tips for pet parents
Keeping your pup at a healthy weight is important for their overall health. Overweight or obese dogs aren’t just carrying extra weight, they’re carrying extra risk for conditions like osteoarthritis, diabetes, and heart disease. Additionally, overweight dogs live shorter lives compared to those that maintain a healthy weight.
As a pet parent, here are some actions you can take that will benefit your dog.
Understand your dog’s baseline tendencies
If your dog is genetically predisposed to higher food motivation, you may notice behaviors like persistent begging or food-seeking. Recognising this as a biological tendency—not just a training issue—can help guide management strategies.
Adjust feeding practices proactively
Measured meals, calorie awareness, and thoughtful treat use become especially important for dogs with higher risk.
Build consistent activity into routines
Regular movement helps support energy balance and overall health. For a starting point on how much exercise dogs need based on breed, check out this article.
Monitor body condition and weight
Body condition scoring (BCS) provides a more accurate picture of health than weight alone. However, regularly weighing your dog may help you notice small increases before they become a bigger issue.
Use genetics as one piece of the puzzle
DNA insights are most valuable when combined with veterinary care, lifestyle management, and ongoing monitoring.
Final thoughts
Obesity is a growing health issue for dogs, but there are steps you can take to help your pup maintain a healthy weight. Understanding their genetic predispositions can guide the actions you and your veterinarian take throughout your dog’s life to ensure they live as long and comfortable a life as possible.
