Pets and Obesity

In 2016, the British Veterinary Association (BVA) questioned over 1,600 vets across the UK to identify what they saw as the biggest health and welfare concern for UK pets.

Over 60 per cent agreed that it was obesity.

The results of this poll are reflected in research by other organisations. The Kennel Club estimates that between one and two thirds of all dogs are overweight, while the PDSA’s Animal Welfare report released in 2014, suggested that a quarter of all rabbits and cats are overweight or obese. It is predicted to continue to rise, with experts believing that within five years over half of all pets will be overweight.

What is obesity?

Obesity is an excess of body fat, which is serious enough to impair health, welfare, and quality of life.

In dogs and cats, obesity is defined as having at least 10 per cent more body weight than their ideal weight.
Many owners may not be aware, but Section 9 of the Animal Welfare Act 2006 requires owners to feed their pet a nutritionally balanced diet and keep them at a healthy weight.

The Code of Practice for the Welfare of Dogs produced by the British Government states that owners should:

‘Make sure your dog eats a balanced diet suitable for its individual needs and maintains a stable weight that is neither over nor underweight for its age, level of activity, sex, breed and state of health. Do not let your dog overeat or it will become obese, and do not feed too little or your dog will be underweight.’ (

The causes of obesity

The causes of obesity in pets are the same as for humans.

Overfeeding, whether that is of their normal food, or from giving additional treats, is the main cause. It can be easy to overestimate how much food your pet needs, particularly if they enjoy their food.

Many owners like to share their treats with their pets. Snacks tend to be high in fat and sugar or salt, making them high in calories. Although the snack may be small, or even just a bite, the smaller size of our pets means that they are proportionately more of their total calorie allowance.

A lack of exercise is another major factor. Busy lifestyles mean that many dogs, for example, do not get walked far enough or often enough. Rabbits are usually confined to hutches and get little time to hop around more freely.

However, there are factors that make obesity more likely. These include:

Breed – some dog breeds, such as Labradors, King Charles Spaniels, and beagles are particularly prone to weight gain.

Age – middle aged dogs (5-10 years) are most likely to gain weight.

Gender – females are more likely to gain weight

Neutering – the hormonal changes that occur after neutering mean that spayed or castrated pets are more likely to put on weight.

Some medical conditions can cause weight gain. These include an underactive thyroid (hypothyroidism), insulinomas (pancreatic cancer), and hyperadrenocorticism (tumours, usually non-cancerous, that can grow on the pituitary or adrenal glands). Pet owners should consult a vet to rule out these and other conditions, especially if the gain is rapid.

Health problems

Common health problems seen in obese pets are:

  • Difficulty moving
  • High blood pressure
  • Heart disease
  • Breathing problems, especially in short nosed breeds
  • Diabetes
  • Musculoskeletal issues, such as arthritis and wearing of the joints
  • Shortened life expectancy
  • Certain types of cancer

Identifying obesity

Many owners do not realise that their pets are overweight, as it happens over a period of time.

There are some simple signs that owners can look for. Dogs are a healthy weight if:

  • The outline of ribs can be seen (if the coat is short enough), or easily felt.
  • There is a clear waist when looking from above.
  • The belly isn’t hanging down when viewed in profile.
  • For cats, the signs of a healthy weight are:
    • Being able to see and feel the ribs, spine, and hip bones.
    • A slight curve on the belly, but not sagging.

If your pet does not meet these criteria, owners should consult a vet to have their weight and health checked.

How to reduce their weight

Owners should consult their vet to make sure that there are no underlying issues causing the weight problem, as covered above.

Once it is established that the weight gain is not due to health problems, they will be able to provide advice tailored specifically for your pet.

Your pet may need to change food to meet their needs. This is more likely to be the case if your pet is being fed on a cheaper food that has a low nutritional value. Some owners buy food designed for working dogs, because it is cheaper. The lower cost is due to the fact that no VAT is applied to food for working animals. However, these foods are higher in calories, to supply working dogs with the extra energy they require. It is not suitable for more sedentary pets.

Dog food manufacturers produce a range of foods tailored towards different ages and circumstances. These include puppy or kitten food, low calorie versions, and food designed for older pets. They will have different compositions designed to meet the needs of those groups. Feeding the right food will make a difference.

Once a suitable food has been identified, owners must make themselves aware of the portion size their dog needs. The food should be introduced over a few days, by mixing it with their regular food, gradually increasing the amount of new food, and reducing the amount of old food. This will help to prevent stomach upsets. It is better to feed the pet little and often.

If owners want to give treats, these should be suitable for your pet, i.e. low in fat, sugar and salt. There are suitable treats on the market, or owners can make their own. There are plenty of recipes available online. Treats must be calculated as part of their pet’s daily calorie allowance, which is easier when feeding commercial treats, as these will have their nutritional value on the packet.

The other step is to increase their activity levels. Two walks a day are better than one, although the total recommended exercise time can be split between the two. Dependent on their breed, dogs should be exercised for between 30 minutes and two hours per day. Additionally, playing ball in the garden (using a suitably sized ball), or other games, will increase their activity level without too much effort.


Owners have both a legal duty and a responsibility as a good owner to ensure that their pet receives a nutritional diet and maintains a healthy weight.

Obesity is a growing problem in the UK, and it is easy for a pet to gain a few excess pounds without owners realising. This can cause real and serious health problems. However, a few simple steps can ensure that your pet maintains an appropriate weight, and stays happy and healthy.

Well Done!