Obesity is defined in humans as excessive white adipose (fat) tissue. Surveys in people show significantly increased disease (heart disease, diabetes and some cancers) and premature deaths with increasing human body fat. Recent work suggests Japan had a low COVID death toll because obesity in that population is much less common than in the West. 

Studies for our pets are more limited, and the even the definition of obesity is more disputed. Dogs are considered ‘overweight’ when their bodymass is more than 15% above ideal. They are ‘obese’ when their weight is more than 30% over ideal. 

In vet medicine, we use weighing scales and ‘ideal’ bodyweight charts, depending on the breed of dog to assess plumpness. Vets are also increasingly using Body Condition Scoring – that is, measuring how much body fat the dog has, as well as merely measuring how many kilos they weigh. This makes a lot of sense: if you have a well-muscled and tall Labrador in perfect body condition weighing 40kg, this is very different from the short-backed, small, obese Lab who also weighs 40kg – this illustrates the limitations of just using scales. 

Body Condition Score tables are designed and published by Royal Canin, for example. You can find them at https://www.royalcaninhealthyweight.co.uk/pet-obesity. Beware, though, many vet nutritionists think these tables are a bit on the generous side. For example, on a 1-9 scale, 5 is in the middle, suggesting it’s ideal. Most raw feeding vet nutritionists think 4/9 is a healthier ideal using these score charts from a kibble manufacturer. 

In the UK, over 70% of dogs are obese or overweight. Obesity used to be considered an inconvenience and somehow ‘cuddly’ or, “well, he’s just got big bones”, and other painful excuses. Canine obesity classed, officially, as a ‘disease’, consistent with its classification in people. It is now considered a chronic illness – that is, a long term issue that needs addressing for the health and welfare of the patient, like heart or kidney disease. 

In dogs, obesity is associated with osteoarthritis, type 2 diabetes, high blood pressure, heart and respiratory disease, kidney disease, cancer and more. This is really serious stuff if you want a healthy dog to live out their full life potential! And 7/10 dogs have this disease of obesity, mainly due to inappropriate diet. Obese pets are 15-30% more expensive to care for over their lifetime and can live up to 2 years less than a trim sibling! 

When I talk to owners about obesity, they will often say ‘Oh, yes, well, he hasn’t been getting as much exercise recently’. This may be so, but science tells us that exercise is only a small part of body weight control, perhaps as little as five per cent, depressingly. Human nutritionists are known to warn, ‘you can’t outrun a bad diet’. 

But all is not lost. Changing diet can influence body fat. Using conventional foods, unfortunately, the success rate, even with the most qualified university vets in the UK, is poor. Only 50% of dogs reach target weight on any given processed food. Surprisingly, of those only half remain at ideal weight! That’s a 75% failure rate with the top vets and the top university obesity clinics, using tins and dry kibbled food. Beware. 

Vets’ experience up and down the UK, with feeding a species-appropriate fresh or raw diet is much better. We don’t have official figures, but most of us raw feeding vets will assure you that they have a much better success rate when using a good quality raw food diet.