A dog turning their nose up at dinner can be worrying, but it is not always serious. The short answer is this: a healthy dog missing one meal, or eating a little less for a day, is often nothing to fret about, especially if they are otherwise bright and lively. But a lost appetite that lasts, or comes with other signs like being flat, sick or in pain, is a reason to speak to your vet, and a puppy or a small dog who will not eat needs attention much sooner.
A loss of appetite has a proper name, inappetence or anorexia, and it simply means "not eating," a symptom rather than a diagnosis. The real question is always why. Here is how to think it through.
When a skipped meal is nothing to worry about
Dogs are not machines, and a slightly smaller appetite now and then is normal. Common harmless reasons include:
- Warm weather: many dogs eat less when it is hot, just as we do
- A recent big meal, treats or table scraps: they may simply be full
- A change of food: fussiness or mild reluctance when the recipe changes
- A quieter, lazier day: less exercise can mean less appetite
- Being a bit of a fusspot: some dogs hold out for something tastier
If your dog is happy, playful and drinking normally, and skips a meal but eats the next one, that is usually fine. The pattern to watch is whether it passes quickly or drags on.
Worth knowing: Try not to solve fussiness by constantly upgrading to tastier food, as clever dogs quickly learn that refusing dinner brings something better. Offer their normal food, take it up after fifteen or twenty minutes if untouched, and try again at the next meal, as long as they are otherwise well. If you are genuinely unsure whether it is fussiness or illness, check with your vet.
Common reasons a dog goes off their food
When the loss of appetite is more than a passing fuss, there is usually an underlying cause. Some of the more common ones:
- Feeling unwell: an upset stomach, nausea, an infection or a fever
- Dental pain: sore teeth or gums can make eating uncomfortable, so watch for dropping food or eating on one side
- Pain anywhere: dogs in discomfort often lose interest in food
- Stress or change: a house move, new pet, kennels, or a change in routine
- Recent vaccination or medication: some dogs are a little flat and off their food for a day afterwards
- Something more serious: a range of illnesses can reduce appetite, which is why lasting inappetence needs a vet
Notice how many of these are things you cannot see. That is exactly why a persistent loss of appetite deserves a proper look rather than guesswork.
When to worry
Use the whole picture, not just the food bowl. Speak to your vet promptly if the loss of appetite comes with any of these:
- Vomiting or diarrhoea, especially if repeated
- Lethargy, weakness, or your dog seeming generally unwell
- Signs of pain, a hunched posture, or drooling and pawing at the mouth
- A swollen or tender tummy, or repeated unproductive retching (this can be an emergency)
- Not drinking, or drinking much more than usual
- Any weight loss you can see or feel
When it becomes urgent
Some situations should not wait. Contact your vet, or an out-of-hours emergency service, the same day if:
- A puppy or a very small dog refuses food, as they can get low on blood sugar quickly
- A dog will not eat at all for more than a day or two, even if they seem otherwise okay
- Not eating comes with vomiting, a bloated belly or obvious pain
- Your dog is also refusing water
For any healthy adult dog, a single missed meal is rarely a crisis. But a dog who is normally keen and suddenly is not, especially with any other symptom, is worth a phone call. The PDSA Pet Health Hub has reliable general advice, and your own vet knows your dog's history best.
Frequently asked questions
My dog won't eat but is acting normal, should I worry?
A healthy, bright dog who skips a meal or eats a little less for a day is usually fine, particularly in warm weather or after treats. Offer their normal food and monitor them. If it lasts more than a day or two, or any other symptom appears, contact your vet.
How long can a dog go without eating before I call the vet?
As a rough guide, an otherwise well adult dog missing food for more than a day or two warrants a call. Puppies, small breeds and any dog with other symptoms such as vomiting, lethargy or pain should be seen much sooner, often the same day.
Why has my dog suddenly gone off their food?
Sudden causes range from the harmless (heat, fullness, fussiness, a food change) to the medical (nausea, dental pain, pain elsewhere, stress or illness). If your dog is otherwise well it may pass, but a sudden loss of appetite with any other sign should be checked by your vet.
Could dental problems stop my dog eating?
Yes. Sore teeth or gums make chewing painful, so look for dropping food, chewing on one side, bad breath or pawing at the mouth. Dental pain is common and treatable, so it is well worth having your vet check your dog's mouth.
This isn't veterinary advice
We're professional dog groomers, not vets, so please treat this as friendly general guidance. If you're worried about your dog, or before acting on anything here, speak to your local vet. In an emergency, contact your vet or nearest out-of-hours clinic.
Fluffs is a professional dog grooming salon in Wigginton, York, offering one-to-one grooming for dogs of every breed and coat type across Haxby, Strensall, Huntington, New Earswick and the surrounding villages. We keep every visit calm and low-stress, which helps sensitive dogs stay settled and eating well around their groom. Book a relaxed, one-to-one groom.