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Why Is My Dog Not Eating?

Dog Staring at Empty Food Bowl

Dog Not Eating Causes and Treatments

If you find yourself with a dog not eating, it could be due to a number of factors—from health conditions to behavioral problems to the type of food you're offering. But figuring out the exact reason why can be difficult. "Dogs obviously can't communicate the reason they stopped eating to us," says Dr. Justin Shmalberg, a DVM and Nom Nom's veterinary nutritionist, "and then there's the fact that dogs are designed for extended fasting. Although they're very food-motivated, dogs can go some time without issues on no food as long as they're otherwise healthy."

Yet, to properly treat a dog's loss of appetite, you have to know what's causing it. That's where we come in. We've put together a guide to the most common causes of hyporexia (reduced food intake) and anorexia (complete refusal of food) in dogs, and steps you can take—usually with the help of your vet—to get your best friend eating again:

Common Causes of Loss of Appetite in Dogs

Why won't my dog eat? This is a question vets hear fairly often. If a dog refuses to eat, it's usually either a behavioral issue or a health-related problem. In the former case, there's some good news: dogs whose appetite loss is related to behavior are still usually willing to eat some foods—especially new diets or treats. "Complete prolonged food refusal is rare without an underlying medical reason," says Dr. Shmalberg. Below are common behavioral reasons that might be behind the loss of appetite in dogs.

Behavioral Reasons Why A Dog Won't Eat

Your Dog is Picky

Dogs typically aren't born picky—rather, they learn to be picky. This is most common in smaller dogs who've been offered a range of foods. Extra offerings can provide way more calories than owners realize so that a dog doesn't feel as hungry and may wait for something better to come along. Another thing to note if your dog won't eat dog food? Those who get table scraps tend to be pickier than those who don't. Same goes for dogs who aren't fed on a schedule—those who learn they eat at certain times are far more likely to eat than those who aren't sure when their next meal is coming.

How to tell if pickiness is the issue: A picky dog will often refuse to eat familiar foods—but get extremely excited about new or high-fat foods and table scraps

There is Something Wrong with the Food

What causes a dog not to eat could come down to food quality, including the following scenarios:

How to tell if food quality is the issue: If you offer your dog a new batch of her usual food and she eats it right away, that's usually a giveaway the old batch may have gone bad. If you were feeding kibble and try something with similar ingredients and flavors, but in a wet form, this often indicates it's an aroma issue. Both scenarios are a little different than having a picky eater.

Your Dog Could be Bored of His/Her Food (A Common Myth)

If your dog stopped eating, could he just be bored of his food? Most likely not, according to Dr. Shmalberg. "This appears to be very uncommon without some other factor, like the introduction of new foods or treats," he says. "Many dogs are content to eat the same diet for as long as it's offered. If a dog doesn't know other options exist, he's pretty unlikely to get bored." When a dog suddenly decides he just doesn't want a food anymore, he could have been trained to become picky, or it could be due to something we can't detect, like a slight change in ingredients that alters the flavor. As they age, dogs do seem to be more likely to stop eating a food for no apparent reason. Whether this has to do with changing flavors or true boredom is unclear.

How to tell if boredom is the issue: If your dog appears to get "bored" by his food, switching to a new flavor in his same food or category. For example, going from a beef fresh diet to a chicken fresh diet may do the trick.

Your Dog Gets Too Many Treats

Treats are pretty much a surefire way to make your dog pickier. "Dogs love novelty and when they get a ton of treats, of different types and flavors, they want the same thing from their food," says Dr. Shmalberg. And then there are the calories. Some standard-sized baked bones pack in 50 calories or more—that's 5 percent of the calories a 50-pound dog with an average activity level needs in a day. Add a few of those into the mix, and it's easy to see why a dog might turn down a meal.

How to tell if an excess of treats is the issue: Trial and error is pretty much the only way—try reducing the number of treats, sticking to lower-calorie options, or offering treats only on a set schedule.

Your Dog is Sensing Household Stress

New animals or people can be stressful to dogs, especially those who are older, routine-driven, or naturally shy. And stress may reduce a dog's desire to eat because she's focused on what's going on around her rather than food.

How to tell if stress is the issue: Assess whether your dog is showing cyclical enthusiasm for her food based on how routine her environment is. Dogs with new, permanent changes in the house (like a new pet or baby) usually go back to their usual eating habits after a week or two.

How to Help a Dog Who Won't Eat Due to Behavioral Reasons

If you suspect your pet's issue is behavioral, try the following strategies. Ultimately, remember that if you don't establish some food boundaries, your dog will be the boss of you and not the other way around.

Dog Not Eating Due to Health Reasons

According to Dr. Shmalberg, the complete refusal of any food (treats, meals, etc.) is far more concerning but less common than the refusal of only certain foods. If a dog won't eat but drinks water or a dog refuses food altogether, it could be a sign of a health problem. Here are some possibilities.

Dental Problems in Dogs 

When dental problems arise, such as loss of teeth, tooth and jaw infections, etc., a dog may not let his owner know that he is in pain. However, he may reduce his food intake, drop food, or refuse food (especially hard foods like kibble). Dr. Shmalberg also points out that objects can get stuck in a dog's teeth. "I once saw a dog who had a stick lodged in his teeth that had been there for two weeks, and started to destroy the tissue on the roof of his mouth," he says. "The only symptom was that the dog stopped eating!"

How to tell if a dental problem is an issue: If your dog stopped eating, it's not a bad idea to look in your dog's mouth. Foul odor, loose teeth, large amounts of calculus (colored, mineral-like material on the surface of the teeth) can all be signs something is awry—but checking yourself is no substitute for a professional exam. See your vet as soon as you can if you suspect a dental issue.

Stress and Anxiety in Dogs

There are certain conditions that parallel human psychiatric diagnoses that may impact a dog's eating habits. Separation anxiety, generalized anxiety, and aggression appear to override appetite in some pups.

How to tell if a mental condition is an issue: Talk to your vet or an animal behaviorist if you see episodes of not eating along with severe behavioral signs.

Physical and Medical Conditions

Most prolonged cases of a complete refusal of food (anything that lasts more than three to five days)—and many cases of chronic undereating—stem from a specific physical or medical condition, like one of the following.

How to tell if a physical or medical condition is the issue: Consult a professional. Your vet can do a thorough exam to try to localize the issue and may run additional blood work, urine, and fecal exams, and other tests to help check for internal medical disorders.

Dog Receiving Recent Vaccinations and New Medications

A visit to the vet, as much as your veterinary team tries to make it comfortable, can still be stressful for your dog. There, she may be given routine preventative medicines (like a deworming agent), and the entire experience can cause a temporary decline in appetite. It's usually nothing to worry about, as dogs typically get right back on schedule.

Vaccinations, too, cause—intentionally—a brief inflammatory response, which may lead to a day or two of your dog eating a little less or refusing food altogether. This is totally normal. New medications can also affect your dog's appetite. If they're added to the food, that may change the flavor and give your dog pause come mealtime.

How to tell if a vaccination or medication is the issue: If changes in eating coincide with a new medication, or if your dog stops eating for more than two days following a vaccination, either of those could be the culprit. Give your vet a call to discuss.

Age of Dog Impacting Diet

As they age, dogs may become less active and eat less to maintain their weight. This isn't concerning if they're still in good shape. (Remember, the suggested feeding amounts on food packages usually overestimate what normal dogs need.)

If a senior dog is otherwise healthy, cognitive changes could impact his eating schedule or frequency, too. That in mind, get in the habit of taking any senior pet in for routine checks.

How to tell if age is the issue: If you notice—along with a lack of appetite—shifting sleep habits or strange behaviors or vocalizations in your dog, or if he just seems distant or absent. Call your vet, who can prescribe supplements or new foods that can help keep your dog on track in his twilight years.

How to Help a Dog Who Won't Eat Due to Health Reasons

If you suspect a health or medical cause, consult a vet. Many of these conditions come with vague symptoms in dogs that require close examination in order to land on the right treatment. A careful physical exam will often help to narrow the search for the cause; if necessary, your vet will order more detailed exams (like blood work, X-rays, an ultrasound, or urine or fecal testing) to glean further information.

And keep in mind that most cases of complete food refusal caused by a medical condition will not improve without addressing the underlying cause.

To help dogs with underlying disorders get back to eating, in addition to visiting your vet, here are some basic steps you can take:

How Long Can A Dog Go Without Eating?

Just how long can a dog go without eating, anyway? Let's talk normal dogs first—that is, dogs without any underlying medical issues. "Dogs are extremely good at being normal while not eating. Their wild ancestors evolved to eat huge meals all at once, and then eat nothing for a period," says Dr. Shmalberg. "Sled dogs in the off-season, as one example, can be fed just once a week in some cases and function normally."

All that said, if you have a dog who's picky, finicky, or just playing you for "better" food she likes more, in a battle of the wills, the dog usually wins. Normal dogs will fast for up to five days—sometimes longer—to get what they want. If you think your dog falls into this category, talk to your vet and get her checked out. If there's nothing wrong, and she's driving you crazy, it may be time for tough love!

Anorexia in Dogs 

If your dog isn't eating enough and you suspect an underlying condition—and she's losing weight—have her checked out. Here are some signals it's time for a vet visit (and potentially a new eating strategy):

Dogs' bodies are very good at maintaining normal organ function in order to survive a very long period of anorexia. However, anorexia in dogs can cause a number of long-term dangers including:

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