Obesity in dogs

Isolated dog


  • Vets estimate that nearly half of dogs in the UK are overweight!
  • Being obese puts your dog at risk of health problems, and is likely to reduce how long they live.
  • It’s important to know what your dog’s ideal shape is and recognise when it changes.
  • You can control your dog’s weight with diet and exercise.
  • Contact your vet if you are struggling to keep your dog at an ideal weight, they will always be happy to help.
  • Download our guide: ‘Food and fitness for a healthy dog’.

Is my dog overweight?

The best way to assess your dog is to look at their shape, their weight may fluctuate throughout life, but their ideal shape stays the same.

How to check your dog’s body shape:

  1. Look at your dog from the side and from above. They should have a smooth, tucked-in waist.
  2. Feel under your dog’s tummy. It should go in, not bulge out.
  3. Feel along your dog’s side and back. You should be able to feel your dog’s ribs, spine and hipbones quite easily but they shouldn’t stick out.
  4. Feel the base of your dog’s tail. There shouldn’t be any build-up of fat where the tail meets your dog’s back.

Give your dog a ‘body condition score’ using our body condition score chart.


So, why is your dog overweight?

Diet and exercise:

If your dog has gained weight, it’s likely they are eating too much or moving too little. ‘Eat less, move more’ – this simple formula really does work.


Medical conditions that cause weight gain in dogs include hypothyroidism and Cushing’s disease. These conditions often also cause symptoms such as coat changes, low energy and increased thirst, contact your vet for an appointment if you are concerned. It’s important to note that these conditions are a much rarer cause of weight gain than an exercise and diet imbalance.

Health risks

Overweight dogs are at risk of:

  • A reduced lifespan
  • Arthritis
  • Urine incontinence (leaking urine)
  • Back problems
  • Cruciate ligament problems
  • Breathing problems such as windpipe collapse and laryngeal collapse
  • Breathing problems in flat faced breeds
  • Cancer
  • Heatstroke
  • Injury.

The best diet for an overweight dog

Read our advice on feeding your dog.


Read our advice on how much exercise your dog needs.

When to contact your vet

Contact your vet if you are struggling to keep your dog a healthy weight, they will be very happy to help.

We understand how difficult it can be to get your dog to lose weight and for this reason many vet practices run weight clinics. Most also have weighing scales in their waiting room that can be used without an appointment.


Once your dog has reached their ideal shape they will be healthier, happier and more active. They will have the best chance to live a long, healthy life.

We understand how hard it can be to get your dog to lose weight but trust us, it’s worth all the effort.


Research before you get a dog

  • If you choose a dog that doesn’t fit in with your lifestyle, weight and behavioural problems are likely to develop. It’s easy to get carried away with how a breed looks when actually, it’s much more important to find a dog that suits you and your family.
  • If you’re an active person, a dog that needs lots of exercise will be fine.
  • If you are less active, and would struggle to give them the exercise they need, a lower energy dog would suit you.
  • Find out more regarding how much exercise your dog needs and about each breed on our breed pages.


  • Making sure your dog has enough exercise is as important as feeding them correctly. The more they move the more calories they burn.

Food and treats

  • Feed your dog the right amount and only give them healthy treats. When giving them their evening meal, think about how many treat’s they have had that day – if they have had lots, they won’t need as much dinner (no matter what they tell you)!


An overweight dog is much more likely to develop health problems than a dog in good shape and as a result, they tend to cost more. To keep vet bills as low as possible, keep your dog at a healthy weight.

Consider insuring your dog as soon as you get them, before any signs of illness start. This will ensure you have all the support you need to care for them throughout their life.

Published: March 2019

PetWise Pet Health Hub – brought to you thanks to support from players of People’s Postcode Lottery 

Written by vets and vet nurses. This advice is for UK pets only.

Illustrations by Samantha Elmhurst