Most dog owners know the sinking feeling of putting down a bowl of food and watching their pup walk away without even a sniff. While the occasional missed meal usually isn’t cause for panic, a dog that refuses to eat for more than a day or two, or shows other troubling signs, shouldn’t be ignored. Dogs are usually enthusiastic eaters, so a sudden loss of appetite can point to an underlying issue.

Why Won't My Dog Eat?

There isn’t one simple answer. Dogs stop eating for many different reasons. The reasons could be medical, behavioral, and may even be related to the food itself. Illness, dental pain, stress, or even something as simple as too many treats can play a role.

First, don’t panic. Observe your dog closely. Check for other symptoms such as vomiting, diarrhoea, drooling, bad breath, lethargy, or weight loss. If your dog skips just one meal but is otherwise acting normal, you can usually wait and see. But if the loss of appetite lasts more than 48 hours, or comes with worrying signs, a vet visit is the safest option.

Medical Reasons

Medical conditions are some of the most serious causes of appetite loss. If your dog isn’t eating and also seems unwell, don’t delay contacting your vet.

• Gastrointestinal issues – Stomach upset, constipation, inflammatory bowel disease, or even a blockage from swallowing something they shouldn’t can all lead to nausea and food refusal.
• Organ dysfunction – Dogs with liver disease, kidney failure, pancreatitis, diabetes, or certain cancers may lose their appetite because they feel generally unwell.
• Dental disease – Painful teeth, gum infections, or oral injuries can make chewing unbearable. Even if the food smells tempting, eating might be too painful.
• Geriatric dogs - Changes in appetite in older dogs could be due to illness, tooth pain, poor eyesight, pain from joint problems or it could be a sign of canine dementia. Their sense of smell can also decrease as a pet gets older, which might make food less appetising.
• Side effects from medications or vaccinations – Some drugs or recent shots may temporarily lower appetite. This is usually short-lived but worth monitoring.

Medical causes should always be ruled out first, since some can be life-threatening if ignored.

Behavioural Reasons

Dogs, like people, can go off their food for emotional or behavioural reasons.

• Stress or anxiety – Moving house, a new pet, or loud noises can make a dog too nervous to eat.
• Routine changes – Dogs thrive on consistency. Skipping walks, feeding at odd times, or travel can disrupt their appetite.
• Picky eaters – Some dogs simply develop fussy habits. They may prefer a certain flavour, texture, or even refuse food if they’ve been spoiled with table scraps. Once a dog learns that refusing food gets them tastier options, the behaviour often repeats.

Overfeeding

It’s easy to overlook this one. Many dogs refuse meals because they’re already full. Treats and snacks should make up no more than 10% of the daily calorie needs. Too many treats, chews, or shared human food can fill them up, leaving little appetite for their regular diet. Cutting back on extras and sticking to a consistent feeding schedule can solve the problem quickly.

Problems with the Dog Food

Not all food refusals are about the dog. Sometimes, the food itself is the problem.

• Spoiled or stale food – Dogs can smell when kibble or wet food has gone bad even if we can’t. Always check expiration dates and storage conditions. To ensure freshness of dry dog food, it’s best to keep them sealed in their original bag, and place the whole bag in an airtight food storage container.
• Sudden diet change – Some pets take time to adapt to new tastes in food. Switching brands or types of food too quickly can upset your dog’s stomach or cause them to reject the unfamiliar taste. 
• Texture or flavour dislike – Some dogs prefer wet food over dry, or vice versa. Others may dislike certain proteins (like lamb or fish).

If your dog suddenly stops eating after you’ve opened a new bag, pouch or can, it might be worth checking freshness, doing a gradual food transition, or reverting to their old diet temporarily.

How to Make Mealtime More Appealing

If your dog is healthy but simply reluctant to eat, you can try these tricks to make mealtime more appealing:

• Warm it up – Slightly warming wet food or kibble with a splash of warm water or bone broth can release stronger aromas.
• Mix-ins – Adding a spoonful of cooked meat, eggs, or freeze-dried meal mixer can tempt picky eaters while still keeping meals balanced.
• Hand-feeding – Offering a few bites by hand can encourage nervous dogs to start eating. For stressed, anxious dogs, try feeding them somewhere they feel comfortable and calm, and make sure that they have access to plenty of clean fresh water.
• Dog bowl size and design - It’s important to get the right bowl size. The visual size of the bowl, and the amount of food owners think they are putting in, can affect the amount of food consumed, leading to overfeeding or underfeeding. Different bowl materials and shapes can also influence the dog's eating posture and digestion; making a dog uncomfortable or reluctant to eat. Flat-faced breeds do best with wide, shallow bowls, while deeper bowls are for long-nosed breeds like Collies. Certain breeds and older dogs with weaker hind legs may benefit from an elevated bowl though this isn't recommended for dogs prone to bloat.
• Puzzle feeders or Food Dispensers – Turning meals into a game may spark interest in eating again.
• Stick to a schedule – Put food down for 15–20 minutes, then remove it until the next mealtime. This reinforces routine and prevents grazing.

Just be careful not to create “fussy eater syndrome” by constantly swapping foods or overloading meals with toppers.

When You Should See the Vet

A temporary dip in appetite isn’t always alarming, but you should call your vet if:

• Your dog hasn’t eaten in more than 48 hours.
• They’re also vomiting, having diarrhoea, or acting lethargic.
• You notice weight loss, bad breath, drooling, or difficulty chewing.
• They’ve recently swallowed something unusual (like a toy or bone fragments).
• Loss of appetite is paired with other chronic symptoms (increased thirst, frequent urination, coughing, etc.).

Trust your instincts. You know your dog best, and if something feels off, it’s always better to get them checked.

Dogs usually love their food, so when they don’t, it’s a clear signal that something isn’t right. Pay attention to their behaviour and eating patterns, cutting back on extras, checking food freshness, and making meals more inviting, you can often solve minor appetite issues at home. But never hesitate to involve your vet if your dog’s refusal lasts more than a day or comes with worrying symptoms. A healthy appetite is a sign of a happy, healthy dog. So keeping an eye on your pup’s eating habits is one of the simplest and most important ways you can care for them.

KATHERINE KHOO

Katherine is a Pet Nutrition Specialist and GDP’s Pet Wellness Advisor. She is committed to helping pet owners make informed dietary and lifestyle choices in nurturing healthy pets. Katherine is also a practicing Nutritional Therapist (human nutrition) and has been helping hundreds of clients to heal naturally with nutrients.