Weight Management in Pets

Too many calories consumed, and too little exercise is a widespread problem throughout our society- for people and pets. If your pet is overweight, it can shorten your pet’s life span, put your pet at a higher risk of certain diseases and overall, reduce their quality of life. Local and international studies estimate approximately 30-40% of all cats and dogs are overweight or obese, and worryingly, this number is continuing to rise. By keeping your pet at its ideal body weight, your dog or cat will have every chance to be healthier and more active, and hopefully, live longer too! 

 Pets that are overweight or obese have an increased risk of a wide range of potentially serious health conditions including:

  • Insulin resistance & Diabetes
  • Cardiovascular disease
  • Reduced exercise tolerance
  • Heat intolerance
  • Breathing difficulties
  • Skin disease
  • Liver & pancreatic disease
  • Bone and joint problems (e.g. osteoarthritis)
  • Urinary tract disease (e.g. urinary stones and infection)

Common causes of obesity

Obesity, by definition is the excess accumulation of body fat and put simply, is a result of ‘too much energy in, not enough energy out’, where excess calories consumed are stored as fat in the body. 

Excess calorie intake is usually as a result of overeating due to greediness, boredom, or simple overfeeding. It is easy to reward begging behaviour by feeding extra food and it takes considerable willpower not to reward your pet’s mournful eyes, when they try this on you, but it is important that you do resist begging behaviour as it simply rewards your pet, reinforces the behaviour and over time the extra food consumed can lead to obesity.

Feeding leftovers, or giving excessive, frequent, high calorie treats or snacks often contributes to the problem. Treats can be useful training aids, but add extra calories to the diet, so it’s important that they are used appropriately. Some veterinary medications also have the unfortunate side effect of stimulating your pet’s appetite and your vet can advise you if such medications are prescribed and how to avoid your pet overeating.

Insufficient activity or exercise is also an important factor leading to obesity in pets, where the calories consumed in a day are not used up. Most of our pets, like us, live fairly sedentary lives and so incorporating regular exercise into their day is important to helping them maintain an ideal body weight. 

Neutering has many known health benefits however can contribute to weight gain. The hormonal  changes that occur post neutering can have an effect on your pet’s metabolism, increasing their tendency to gain weight. On average, your pet may require up to one third less calories in a day after neutering, so it is best to consider an appropriate diet and speak with your vet about the recommended daily amount.  

Your pet’s ideal body condition

You can assess your pet’s weight and body condition by estimating their body condition score. This is done by observing your pet from the top and the side, and by palpating or feeling your pet over key areas such as their ribs and waist. It can take a bit of practice to master, but it’s a technique your vet will be able to teach you. 

You should always consult your vet for further advice if you suspect your pet is overweight. Your vet will conduct a thorough physical examination and may recommend a weight loss program under veterinary supervision for your pet. 

Your vet can give you an estimate of your pet’s ideal body weight, and then provide advice about the type and quantity of food your pet needs to be fed each day until it reaches its target weight. Your vet may prescribe a special veterinary diet if your pet is overweight or obese and needs to achieve a significant weight loss.

Body condition score charts (see below) for dogs and cats will help you to estimate your pet’s body condition score –  this helps determine if they are underweight, overweight or at an ideal body weight. If your pet is overweight, body condition scores provide a means to estimate how much weight your pet may need to lose. 

The WSAVA Body Condition score charts is an independent scoring system.

Dogs: https://www.wsava.org/WSAVA/media/Arpita-and-Emma-editorial/Body-Condition-Score-Dog.pdf 

Cats: https://www.wsava.org/WSAVA/media/PDF_old/Body-condition-score-chart-cats.pdf

Some pets, especially those that have been overweight previously or have an insatiable appetite for food, will tend to regain weight. There are a variety of pet foods available that are “lighter” in calories than standard foods. These are usually clearly identified on their labels and can be a more convenient and often more effective way of keeping their calorie intake under control.


Achieving and maintaining a healthy body weight is not all about diet!

Regular exercise and activity is good for slimming animals (and owners!) as it helps to burn excess calories. When used in conjunction with a calorie-controlled diet, exercise can help your pet shed those excess kilos faster.

For dogs, going on regular walks, is a great way to incorporate exercise into the daily routine. For dogs that are significantly overweight or obese, swimming is preferred to help reduce stress on the joints. Dogs and cats   can also be encouraged to exercise more at home through play with toys or people, providing more access to outdoor areas and feeding their food through interactive feeders designed to encourage activity.

Ensuring that your pet loses weight takes time and a strong commitment from you. For pets that are significantly overweight, it can take more than 6 months to safely reach an ideal body weight!  Any weight loss program for your pet should be developed in consultation with your veterinarian and be regularly monitored.  

Tips for weight loss in your pet

  • Feed only the recommended pet food, with no additional leftovers, scraps, snacks, treats or supplements
  • Organise regular weighing of your pet and record these, ideally charting progress over time
  • Ensure that only one person in the household feeds your pet to avoid overfeeding
  • Always measure the food using scales rather than a cup measurement as scales are more accurate
  • Feed smaller meals more frequently, dividing your pet’s daily ration into 2 to 4 meals
  • Explore and commit to new ways to get your pet active through the day
  • Remember, exercise and play are better rewards than food!

This article is for general information only:
This information is provided by the PFIAA as general information only. For advice and information concerning feeding your individual pet, we recommend that you seek the advice of your veterinarian.