One of the first things I ask a client with a dog who is reactive or aggressive is, “What and how often are you feeding him?” You might be surprised at just how often diet, food quality, and feeding schedules are the culprit of behavior issues. Sometimes just a food change is enough to shift things.

There are many studies out there that show that food directly affects a dog’s behavior. As a holistic trainer and behaviorist, I believe that identifying potential food issues is just as important as addressing the behavior from a training perspective. Here are some ways that food can affect your dog’s behavior.

Not Having a Feeding Schedule, or Not Feeding Often Enough

Many times when I have a client with a puppy that they claim is acting aggressively, it’s because the puppy isn’t getting fed as often as it should. It’s aggressive because it’s starving!

Basic guidelines suggest that a puppy younger than 3 months have at least four meals a day. 4 to 6 month old puppies can eat three times a day, and from six months on, they can be fed twice a day. Just like human babies, they are growing fast, so they burn calories quickly.

Most adult dogs do well on 2 meals a day. Size does matter, though because in general, smaller breeds have higher metabolisms than larger breeds. (1). If you’ve got a small breed adult dog with aggression issues, try feeding smaller portions 3 times a day.

Feeding dogs on a regular schedule can have a healthy emotional impact on them. “They'll learn that they have access to water and consistent meals, regular exercise and mental enrichment, and that they have a safe place to be in their new home,” says behaviorist Cathy Madson. (2)

For breed and size specific feeding information, check out this feeding chart.

Food Allergies

Food allergies can affect the nervous system and cause inflammation. The discomfort from them can be a factor in your dog’s behavior, including reactivity and a short temper.

If your dog is eating something that he or she is sensitive to daily it can affect gut bacteria. A recent study shows that a dog’s gut biome is linked to anxiety and aggression. (3)

Poor-Quality Protein and Other Ingredients

It can be a challenge to feed your dog a healthy diet, especially if you are giving him kibble. Dog food manufacturers spend a lot of time and money making sure that it appears their food has everything your dog needs, but unfortunately, this is far from the truth.

Most commercially available dog kibble is made with ingredients considered to be feed-grade instead of human-grade. Feed-grade ingredients are lower quality than human-grade, which means they have less nutritional value.They often come from rendering factories that obtain carcasses from animals that died of illness and old age, and traces of euthanasia drugs have even been found in certain foods.(4)

If your dog counter-surfs, is food aggressive, or guards food, toys, or treats, chances are he or she isn’t getting enough high-quality protein, or may be getting too many carbohydrates.

Imbalanced Diet

Dogs need a balanced, species and breed appropriate diet, which will help them avoid organ-related problems that affect body systems.

A 1997 African study suggests that customizing the diet according to the dog's nutritional needs and preferences can help curb aggression. The researchers studied 100 dogs of various sizes and breeds with a range of behavior problems over a period of five years. When given the option of what to eat, most dogs chose fresh meat and other species appropriate food. Ninety-eight percent of dog owners reported dramatic improvement in aggression and other problem behaviors.

The researchers came to the conclusion that when dogs don't get adequate amounts of food appropriate to their needs, physical hunger motivates behavior problems. An adequate canine diet is an “unequivocally therapeutic” way of reducing aggression and other antisocial behavior in dogs. (5)

Feeding Location and Environment

It’s important for dog parents to be conscious of how their dogs feel about the location of their food. They need to feel comfortable putting their head in a bowl to eat, but dogs can have different ideas about what makes them feel safe.

My dog Mischa is a chihuahua who almost starved to death. She can’t be fed in a crate because her trauma causes her to hoard food instead of eating it. She also isn’t comfortable eating in high traffic areas where people and other animals are. I have to feed her separate from the other dogs, when there is very little noise or movement. It’s the only way she will eat without becoming reactive.

On the other hand, my severely abused rescue-dog Tbone prefers to eat in his crate where he has control over his food and water.

Too Many Carbs

High-carb diets and other unhealthy foods can cause inflammation and obesity in dogs, which can lead to mood disorders like depression and anxiety. Bacterial toxins that normally live in the gut called lipopolysaccharides are the culprit when a dog has too many carbohydrates in its system.

Lipopolysaccharides destroy the brain cells that create serotonin and dopamine, the “feel good” hormones that keep both humans and animals happy and calm. (6) They also decrease inflammation, which can cause behavior issues. (7)

Poor Feeding Etiquette

Certain celebrity dog trainers who shall remain nameless suggest that dog owners can curb resource guarding and food aggression by taking a dog’s food bowl away, or putting a hand in the bowl. This is a great way to get yourself bit, and can actually cause aggressive behavior.

Taking food away without establishing trust first is never the right choice, and can actually make food aggression even worse. How would you feel if I walked up to you at your dinner table and took your plate away? Even if you know me well, I’m pretty sure you wouldn’t like it and may react in an angry way.

Let other pets take another dog’s food away and guardians not ensure proper feeding protocol can trigger food related disputes

While it’s important to be able to redirect your dog away from something he or she is eating that may not be good for them, a better way to do that is by having something of greater value to offer them in exchange for their bowl. If I have a plate of veggies in front of me, and you replace it with filet mignon, I most likely won’t complain about it.

Food aggression is usually a sign of a lack of trust toward the dog parent. If you have a dog with any type of resource guarding, go here for more information.

The science picked up on this issue and I believe they have a good lead!

Recent research links the compositional diversity of the gut microbiome to behavioral and psychological regulation in other mammals, such as mice and humans.

“In terms of how microbes potentially influence dog behavior, this lays the foundation for how aggression and gut microorganisms may be connected,” said lead author Nicole Kirchoff, a graduate student in microbiology in the OSU College of Science. “To our knowledge no other study has looked at the relationship between dog aggressiveness and gut microbes.”

“Aggression is really stigmatized,” said study co-author Monique Udell, an animal behavior researcher in the OSU College of Agricultural Sciences. “It tends to get viewed as a shortcoming of the individual animal. But it’s important to look at aggression and other behavioral syndromes in terms of physiology as well. Maybe there are underlying physiological causes we can address, or if not, maybe there are behavioral predictors with physiological implications.”

Roman Gottfried is an internationally renowned Holistic Dog Training and Dog/Human Relationship Coach. He works with dog parents worldwide in-person and online to help their dogs reach their full potential. He teaches them the holistic philosophy of creating a healthy relationship with their dog. Visit holisticdogtraining.org for more information.