Obesity in dogs

Written by Dr Andrew Miller MRCVSDr Andrew Miller MRCVS is an expert veterinary working in the field for over 10 years after graduating from Bristol University. Andy fact checks and writes for Pure Pet Food while also working as a full time veterinarian. Pure Pet FoodPure Pet Food are the experts in healthy dog food and healthy dogs featured in media outlets such as BBC, Good Housekeeping and The Telegraph. Working with high profile veterinary professionals and nutritionists, Pure Pet Food are changing dog food for the better. - Our editorial process

Obesity in dogs is a common problem for modern pets and it is far more than a cosmetic issue. The condition carries many associated health risks and has a distinct physiological impact on your dog’s health and wellbeing.

Alarmingly, the number of obese pets is increasing. More than 51% of all dogs in the UK are now overweight or obese. The problem of obesity in pets is now so great, 100% of vets have voiced concern about the prevalence of the problem.

It’s important to keep your dog’s weight in check as being overweight can seriously affect your dog’s quality of life and lifespan. Obesity in dogs can impair their ability to carry out normal activities, and dramatically increases their risk of developing certain health conditions including arthritis, diabetes, heart disease, and cancer. Not to mention, it has been proven that dogs suffering from obesity live much shorter lives with a higher instantaneous risk of death compared to dogs at a healthy weight.

Equally concerning is the number of owners who seem oblivious to the problem. 68% of owners think their dog is the right size, yet more than half of Britain’s dogs are overweight, leaving a large proportion who genuinely believe their dog is the right weight when they aren’t. Almost a third of all dog owners don’t even know their dog’s current weight or body score, so how can they recognise if it is normal?

By not recognising obesity and the risks it poses, you are putting your pet at increased risk of health problems, affecting their wellbeing, and shortening their lifespan. This is not being hyperbolic either, as the RSPCA classes obesity as a serious welfare issue.

Definition of obesity in dogs

A dog is classed as obese if they weigh significantly more than normal for their breed and gender, and it adversely affects their health. Any dog who weighs 10% more than normal is classed as overweight. An increase of 20% or more from their normal weight classes them as obese.

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In other words, if you own a dog that should weigh 10kg, they are overweight if they weigh 11kg and obese if they weigh 12kg or more.

How can I tell if my dog is overweight?

There are a few telltale signs on whether your dog is overweight or not. From assessing your dog’s body shape to popping them on the scales, here’s how to check.


To visually examine your dog, look straight down at them when they are stood up. A healthy dog should have a clear, defined waist that tucks in between their ribs and hips. When you look at your dog side-on, their belly should sit above their ribcage, making a gentle slope up from their ribs to their belly.

However, if your dog’s waist is much thinner than their ribcage, and their ribs and hips are obvious, then they are underweight. If their waist is in-line with their ribs or protrudes further than their ribcage, they are overweight. Similarly, if you look at your dog side-on and their belly is in line with their ribs or hangs lower, it’s another sign that they are overweight.


A visual examination is not enough, particularly if you have a hairy dog which disguises their shape. Other methods of checking your dog’s weight include feeling their ribcage. You should be able to feel your dog’s ribs under a little fat. If you lay your hand flat on a table and run your fingertips over your knuckles, this feels similar to how your dog’s ribs should feel. You should not feel an excessive amount of fat, and if you can’t feel their ribs at all, your dog is overweight.

Next time you’re sat stroking your pup, pay attention to how they feel. You should be able to feel your dogs spine, ribs, and hips while stroking them. If you can’t feel these bones at all, your dog is probably overweight.

Weigh your dog

Another option is to weigh your dog, and you can do this at home if your scales are sturdy enough. If your dog is too big to stand on your scales, try putting their bed on the scales instead, then put your dog in the bed. Subtract the weight of the bed from the result and you’ll have your dog’s weight which you can compare to breed standards.

Alternatively, make use of the scales at your veterinary practice. Many practices keep the scales in the waiting room and you’re free to use them to check your dog, even if you don’t have an appointment.

What happens if a dog is obese? The risks associated with obesity in dogs

If your dog is obese they are predisposed to many health problems and sadly, their lives are usually much shorter. If your pet is obese they are at risk of developing issues including:

  • Arthritis

  • Breathing difficulties

  • Hormone issues

  • Skin problems

  • Cancer

  • Heart disease

  • Diabetes

  • High blood pressure

  • Decreased life expectancy

The increased weight puts excessive strain on your dog’s body, causing a greater risk of injury. Over time this can lead to problems including sore joints, injured ligaments, arthritis, and even difficulty breathing.

Obese dogs must put increased effort into breathing, which can make them averse to exercise and vulnerable in the heat. They are also at risk of conditions such as tracheal collapse, where their windpipe collapses. Obesity also increases the risk of your dog dying under anaesthesia should they ever require surgery.

Additionally, obesity is a risk factor in a number of canine illnesses. A number of these are life-changing conditions, such as diabetes, or potentially life-limiting, such as cancer and heart disease. Keeping your pet at a healthy weight is the best way to lower their chances of developing any of these conditions and enabling them to live a long and healthy life.

What causes obesity in dogs

There are a few factors which can increase your dog’s likelihood of becoming overweight, including their age, breed, and if they are neutered.

However, the two main factors which cause obesity in dogs are overfeeding and lack of exercise. The principle here is the same as with people, if a dog is not burning calories in proportion to the amount they eat, it will lead to energy being stored as fat and increasing their weight.

Some health issues, such as hyperthyroidism, can cause your dog to become obese. If your dog is overweight it is important for your vet to rule out any underlying health conditions which might be causing the problem.

How can you prevent obesity in dogs?

Thankfully, obesity is a preventable condition. One of the easiest ways to prevent obesity, and all manner of other health issues, is simply to feed your dog a healthy diet in appropriate volumes and give them plenty of exercise.

Diet is the most important way to prevent obesity

Vets advise that food matters most in preventing obesity in dogs. If your pooch is otherwise healthy, it comes down to 70% diet and 30% exercise. The best way to prevent obesity is to feed your dog a biologically appropriate diet suitable for their age and lifestyle.

The best foods use fresh ingredients and are high in protein and fibre, but low in fat. Most of your dog’s energy should be coming from protein, which will boost your dog’s metabolism. Protein and fibre both help your dog to feel full for longer, which can help prevent scrounging and snacking.

However, many processed dog foods are severely lacking. Kibble is a poor source of protein, and the high level of processing further diminishes the available amino acids. Processed dog food also contains significantly higher levels of sugar and fat, with more calories than natural food. Because these calories usually come from cereals, they are “empty”, providing energy but very little nutrition to your dog. It’s similar to comparing a human who eats lots of biscuits and bread to someone who eats balanced meals with lots of fruit and veg.

Biologically appropriate food made with natural ingredients are more nutritious and digestible than kibble, and far more beneficial for your dog’s health. This includes maintaining their hormone production and metabolism, helping them to stay a healthy weight.

Preventing obesity also means monitoring and limiting the treats and tidbits your dog eats too. Many commercial treats and human foods are packed with fat and calories, and even just a few a day can significantly increase your dog’s likelihood to gain weight.

Exercise helps prevent excess weight

Just like humans, a dog’s calorie intake should be proportional to the calories they burn. Yet a worrying 13% of dogs in the UK - that’s 1.3 million dogs - aren’t even walked once a day. The majority of dogs that do have a daily walk still get less than an hour’s exercise. This kind of sedentary lifestyle puts your pet at an increased risk of obesity.

Your dog’s exercise needs will vary according to their breed and age. For example, working breeds like springer spaniels require more exercise than toy dogs. But walking your dog or playing games like fetch helps them to burn excess energy and stay a healthy weight.

If you aren’t sure how much your dog should be eating or exercising, your vet will be happy to advise you.

How is obesity in dogs treated

Just as obesity can be prevented by ensuring your dog eats well and exercises enough, obesity in dogs is treated with a combination of diet and exercise. You will need to reduce your dog’s calorie intake while increasing their level of exercise. This must be done slowly to prevent causing any stress to your dog’s body and keep their weight-loss sustainable.

Your dog may be advised to move to a low-fat, high-protein diet to help them to lose weight. Remember to always introduce new food slowly to prevent stomach upset. You should also stop feeding your dog table scraps and treats as these can carry a lot of “hidden” calories.

When to contact your vet

If you have concerns about your pet’s size or are struggling to get your dog’s weight under control, you should contact your vet. They can examine your dog to determine the best plan to help them to reach a healthy weight.

Potential cost if untreated

If left untreated, obesity can cost you a lot as an owner monetarily and emotionally.

Because obesity predisposes your dog to develop serious health conditions, you’re more likely to be visiting the vet more often. As any owner knows, treating our pets is expensive, and we spend more on our pet’s health than our own. This is especially true if you are having to manage the ongoing cost of treatment for a lifelong condition such as diabetes. Prevention is therefore not only safer but less expensive than the cure.

Vet bills can be a hugely expensive and entirely unexpected cost. For the sake of your dog’s wellbeing, and your wallet, keeping your dog active and at a normal weight will help keep them in good health.

But it isn’t just the monetary cost to consider, there is an emotional cost too. Our pet’s wellbeing is worth more than money, and no owner likes seeing their dog unwell. As pet parents, we want to do the best for our pets and give them long, happy, and healthy lives. One of the easiest and most effective ways to do that is to ensure your dog eats well and stays a healthy weight.

The benefits of getting your dog's weight under control

Both you and your pooch will see the benefits of getting your dog’s weight under control. If your dog has been overweight, getting them to a healthy size can increase their vitality and improve their mood. Previous aches and pains may ease as their joints and organs are under less strain from the excess weight. Your dog is also at lower risk of associated health problems, which is great for their wellbeing and also preventing unforeseen vet bills and heartache for you.

Getting your dog’s weight under control will give you peace of mind, knowing your furry friend’s risk of ill health is decreased, and their life span is extended. On average, dogs at a healthy weight live two years longer than obese dogs. And what could possibly be worth more than your dog’s happiness, and extra time together?

Finally, you will probably be happier too. Exercising with your dog will help you both to bond and give you some great quality time together. Plus, you’ll benefit from the exercise and fresh air as much as your pooch, improving your own health and mental wellbeing. For some inspiration on where to go walkies, try some of our favourite dog walks.

What is the best dog food for obese dogs?

Ensuring that your dog is eating an appropriate amount of calories each day is a great first step towards weight loss. It can be easy to feed your dog too much without realising. For example, kibble contains a lot of carb-filled cereals to bulk out the food and can contain sugar and other additives that contribute to a high calorie count. Fresh food contains fewer calories while still satisfying your dog’s hunger, as the high levels of fibre and protein keep your pup feeling full while providing slow-releasing energy.

The best dog food for obese dogs will also vary according to their age. As dogs get older and their metabolism slows, it becomes easy for them to gain weight. Pure Pet Food is low-fat and packed full of protein and fibre to prevent peckish pups. Our plans are also personalised to your pooch so their food will always be nutritionally appropriate for their age, breed, and size to help them maintain a healthy weight.

Another problem owner’s face with old or overweight pets is that they become exercise averse due to difficulty moving or joint pain. A natural diet will provide nutrients like omega-3 for healthy joints and vitamins like A, C, and K that reduce inflammation and discomfort. If their diet helps to ease their pain and makes moving more comfortable, your dog will become more energetic and active, helping them to lose weight. A nourishing diet will also help maintain normal bodily functions, such as hormone regulation, which can further contribute towards weight loss. Pure’s highly digestible food is made from only natural ingredients, delivering quality nutrition to improve your dog’s overall health.

Pure has helped a whole pack of pups with their weight issues. Charlie the pug used to be quite chunky, but after a switch to Pure he’s become a sleek, well-proportioned pug and said goodbye to his sensitive skin. Similarly, Susy lost 10% of her body weight and is now no longer overweight. (Losing weight wasn’t the only benefit of Pure, as she has also been colitis-free since starting her new diet.)

To see what paw-sitive changes Pure can give your pooch. Tell us about your dog and we’ll recommend the paw-fect personalised plan to help them lose weight and become a happier, healthier pup.