When a Change in a Pet’s Appetite Is Trying to Tell You Something

It takes a lot for instinct to lose an argument with illness. Hunger is one of the strongest instincts any living being has, including our pets. And yet, they can be just as fussy and develop just as many quirky routines around mealtimes as the human members of the family. That’s why a change in appetite can be hard to interpret. Sometimes it’s nothing serious. Other times, it’s the first sign that something isn’t right.

Edgeworth Animal Medical Centre is a local, independent clinic offering thoughtful, lifelong care, including the assessment of health concerns. Whether your pet is turning away from food or eating far more than usual, if anything is out of the ordinary, we’re here to help.

The most concerning symptom, and the easiest for owners to notice, is a complete loss of appetite that lasts beyond a day or so. One day of turning their nose up at food they’re just not that keen on is one thing, but not being able to eat at all is another. This becomes even more important when accompanied by lethargy, vomiting, diarrhoea, pain or behavioural changes.

Prolonged fasting can be especially dangerous in cats. If they refuse to eat for multiple days, they can develop secondary liver issues.

But appetite loss isn’t the only red flag. When your pet suddenly starts eating much more than usual, that’s just as significant. It becomes even more worrying if they’re losing weight at the same time, as that combination is much more suggestive of an underlying disease or condition.

Sometimes, it’s not even about the amount of food. It’s a shift in the way they’re consuming it. For example, if your pet seems interested at mealtime only to walk over to the bowl and then turn away, or you notice them swallowing without chewing, dropping food or chewing on one side, oral pain may be the reason. Pets are incredibly good at hiding this, so by the time you notice these behaviours, they may already be experiencing extreme pain.

Once owners realise appetite changes are more than personality or fussiness, the journey can often lead to unexpected conclusions. Most assume the answer must lie somewhere in the stomach or digestive system. The reality, however, is that it could originate almost anywhere in the body, or it could be a side effect of certain medications. This is why a thorough investigation is so important.

Some of the more common causes we diagnose include:

Dental disease and oral pain
This is often underestimated because many owners simply aren’t aware that dental health can be a serious issue for pets. Dogs and cats will continue eating despite significant pain, so it’s easy to assume their oral health is fine. Unfortunately, identifying the problem often requires a thorough examination and dental X-rays.

Kidney disease
Kidney disease may present as a reduced appetite or unexplained weight loss. Because these changes often develop gradually, they can be easy to overlook until the disease has progressed.

Hyperthyroidism in cats
Hyperthyroidism commonly causes weight loss despite a very good appetite. Owners are often pleased to see their older cat eating so well, only to realise they’re becoming noticeably thinner.

Cushing’s disease in dogs
Cushing’s disease can increase appetite while also causing weight changes, muscle loss and a pot-bellied appearance. These changes often develop gradually, which means they’re easy to overlook at first.

Cancer
Appetite changes can sometimes be linked to cancer, particularly when they’re accompanied by other unexplained changes in your pet’s health.

A classic example of a patient walking out with a diagnosis the owner wasn’t expecting is hyperthyroidism in cats. It can be particularly confusing because, as mentioned earlier, many owners are initially pleased by their cat’s newfound enthusiasm for food. It’s only when the weight continues to drop that they realise something else may be going on.

So, what is hyperthyroidism? It occurs when the thyroid glands produce excessive amounts of thyroid hormone, which increases the cat’s metabolic rate. Cue a constant sense of hunger. Additional signs include increased thirst and urination, restlessness, vocalisation, vomiting, diarrhoea, a rapid heart rate and deterioration in coat condition.

The good news is that a simple blood test can usually confirm the diagnosis, and there are several treatment options available, including medication, dietary management for milder cases and radioactive iodine therapy, which can eliminate the need for daily tablets. Ongoing check-ups remain an important part of care, as bringing thyroid hormone levels back under control can sometimes reveal previously hidden kidney disease.

It’s actually not about a lack of eating. Going back to the idea that many owners think as long as their pet is still eating, they’re fine, this is probably the biggest misconception. Think about how much pain you’d have to be in before you refused to eat. Our pets can’t tell us they’re in pain, so we need to pay attention to all the other clues rather than waiting until they stop eating altogether.

Knowing when to act comes down to knowing what’s normal for your pet. There’s a lot of variation between individuals, from the Labrador that will eat anything and everything in sight, including the garden rocks, to the fussy Toy Poodle who will only eat warmed barbecue chicken and insists on being hand-fed. That’s why, as vets, the first thing we need to establish is their usual behaviour before we can work out what might be happening beneath the surface and which investigations are needed.

There isn’t a perfect appetite that every pet should have, so comparing them to others or relying on generic research probably won’t help you uncover the real cause. No one knows your pet better than you do, so if you’re worried about what’s happening, or not happening, at mealtime, it’s best to have them assessed.

At Edgeworth Animal Medical Centre, we provide comprehensive veterinary care, advanced diagnostics and dental care for furry, feathered and scaly family pets.

Contact us to learn more or book an appointment.

By Dr Nicole Melhem