Obesity: The Fat in the Fire
January marks the time of year we revisit our commitment to beating the battle of bulge in our patients. It’s a good time for it as winter settles in and our canine and feline companions spend more time lounging indoors and indulging in creature comforts (read: treats) in front of their favourite Netflick offering. With more than half of cats and dogs in North America overweight or obese, our aim this month is to focus on pet obesity to nip it in the bud – or the butt in this case (and anywhere else that fat is accumulating).
Keeping Score: How Fat is Too Fat?
We evaluate body fat in cats and dogs using a Body Condition Score (BCS) – it’s our equivalent of human medicine’s Body Mass Index (BMI). At Royal York Animal Hospital, we use the American Animal Hospital Association’s 5-point scale. A perfect score – that is, an optimal body condition – is a 3 out of 5 (give or take half a point, depending on breed, frame size, and other factors). But anything less than 2.5 (way too skinny) or greater than 3.5 (far too fat) will have your vet raise a red flag.
A pet that’s 10 to 19% above its optimal weight has a BCS between 3.5 and 4.5 and is considered overweight. A pet that’s 20% above its optimal weight has a BCS of 5 and is considered obese. That’s right: obese.(The elephant in the room that no one wants to acknowledge.) Obesity is recorded as a medical condition in that pet’s record.We don’t mince words or downplay the fact because an obese pet tips the scales in terms of being at increased risk for a host of health issues. (See “The Fallout of Fat”.) But even pets that are simply overweight suffer the effects of excess fat – and in our experience are on a slippery slope towards becoming obese and more seriously compromised.
To put excess weight for a cat or dog in perspective, a Chihuahua that’s carrying just one extra pound is like a 125-pound woman carrying an extra 30 pounds. Not ideal for either of them.
So how to keep score and stay in the game? Your vet will show you how at your pet’s next exam. And you can refresh your memory with the pictures in AAHA’s Nutritional Assessment Guidelines (see page 4).
The Fallout of Fat: What’s the Big Deal?
Don’t get me wrong. Fat is a good thing. It supplies your pet with energy, essential fatty acids, and the means to absorb fat-soluble vitamins that play an important role in their bodies. But too much of a good thing is, well…bad. And it’s bad on so many levels that it would be quicker to list body systems that excess fat doesn’t affect adversely. (Actually, I’m hard-pressed to think of even one.)
Fat is its own (not so) little chemical factory that pumps out compounds that cause chronic inflammation, oxidative stress, and other damage. I won’t get into the details of the biochemical processes at play here because it gets complicated and my boss has me on a ‘restricted calorie’ word count. (I keep telling her, “My blogs aren’t bloated. They’re just big boned.” but she’s not buying it.)
Suffice to say that diseases associated with, or exacerbated by, obesity include:
- Diabetes Mellitus and Fatty Liver disease in cats
- Hypothyroidism and Hyperadrenocorticism in dogs
- Heart disease, high blood pressure, and respiratory issues
- Kidney disease
- Skin disease
- Orthopedic issues (arthritis and ligament damage)
- Urinary tract issues
- Decreased immune function (including impaired wound healing)
- Cancer (such as insulinomas and transitional cell carcinomas)
And that’s just a partial list. What’s more, an obese pet is one that’s not enjoying life as much as his or her leaner counterparts because of constant pain and compromised cardiovascular function. They just can’t tolerate much activity.
Obesity is an added concern for your veterinarian who can’t properly examine your pet through all that fat and who worries about increased anesthetic complications when your pet has to have surgery for whatever reason.
The bottom line: Obesity significantly compromises a pet’s quality of life and shortens his/her lifespan by up to 2.5 years.
That’s plenty for you to digest in one sitting. Let’s take a break (and maybe go for a walk!). I’ll be back soon to explain how to trim excess fat and get your pet back in perfect form. In the meantime, Happy New Year from all of us at Royal York Animal Hospital.