We know that for humans, specific foods and nutrients produce specific changes in the chemical balance of the brain. These in turn affect both mood and performance. But are the same rules apply to our dogs? Let me explain about nutrition and dog behavior.
Tryptophan
Tryptophan is an amino acid found in protein foods like meat, chicken and fish, and its a precursor of serotonin. Serotonin is a brain chemical associated with feelings of relaxation and calmness, regulates sleep cycles and sensitivity to noise and touch.
Pets absorb tryptophan by eating protein. Another way is by consumption of carbohydrates which raises tryptophan levels in the blood/brain. Diets made mainly from protein sources and low in carbs can cause a shortage of tryptophan. This situation occurs because other amino acids found in protein overcome tryptophan and pass more effectively into the brain. Therefor, lower levels of tryptophan and thus serotonin.
Low levels of Serotonin are associated with increased aggression, especially defensive aggression, and decreased impulse control in dogs. They can also cause dogs to exhibit signs of anxiety, fearfulness and all together be restless.
One study indicated that a diet with high protein concentration (32%) increased fear induced territorial aggression in dogs compared to low (17%) and medium (25%) protein concentrations. It didn’t however affect dominance aggression or hyperactivity. Another study reinforced this point and showed that a low protein diet or a tryptophan supplement reduced dominance aggression, territorial aggression and hyperactivity in dogs.
Simple carbohydrates
As I stated before, feeding carbohydrates raises the level of serotonin which induces relaxation and calmness. This means that a diet with a high carbohydrate ratio may suit dogs who suffer from anxiety or aggression.
In addition, high-protein, low-carbohydrate diets may induce a serotonin deficiency; This in turn could trigger, in some dogs, carbohydrate cravings in order to correct the imbalance. These dogs may not only exhibit destructive behaviors around the house, in their search for food, but sometimes also signs of aggression.
Carbohydrates are transformed into simple sugars by your dogs body. Hence, diets containing large quantities of simple carbohydrate (like many commercial dog foods) cause an increase in blood sugar levels. These in turn can trigger behaviors such as anxiety, hyperactivity, low self control, irritability and fearfulness.
You are probably asking yourself, “to feed or not to feed carbohydrates?”. My advice is to feed balanced amounts of complex carbohydrates. These will allow availability of Tryptophan yet regulate sugar levels in the blood.
Energy surplus
Each dog has its own dietary and energy needs according to his activity level, health status, age and other personal considerations. Excess energy (Caloric) intake is stored as fat tissue by the body. Therefore, constant intake of excess energy will lead in the long run to weight gain.
Obesity is a major health and welfare issue for dogs. It affects their ability to run, jump and play, which may put a damper on their mood. Furthermore, it may lead to serious health issues such as diabetes, cancer and arthritis. These in turn may cause dogs to feel depressed, sluggish, irritable, and less calm.
Energy restriction
When we put dogs on a diet and restrict their energy intake, we could cause them significant frustration. This can manifest as different behaviors such as increased chewing, pawing, licking and holding objects in mouth.
When dogs are put on a diet, they are being fed below the recommended maintenance nutritional needs. Meaning, the body receives less energy than it should in order to operate at a certain minimal level. So, the dogs body starts to conserve energy by lowering its activity level.
Studies showed that dogs given energy restricted diets started showing aggressive behaviors such as snaps, bites, focused barking and fighting. These behaviors decreased significantly as the time on the diet grew longer.
Dietary fiber
Adding dietary fibers to dogs on a weight loss program provides feelings of fullness for longer periods of time. Hence, decrease their hunger and consequently decrease destructive and negative behaviors.
Specific deficiencies
There are some nutrients that the lack of them may result in certain behaviors:
Vitamin B1 (Thiamin) – compulsive behavior, coprophagia, neural issues.
Vitamin B3 (Niacin) – irritability, aggression, low reflexes.
Calcium – fearfulness, irritability, anxiety, disorientation.
Magnesium – aggression, muscle spasms, difficulty learning and memory problems.
Manganese – irritableness, allergies, deafness.
These deficiencies can only be known once conducting a blood test and so it’s always better to talk to your vet if observing behavioral changes.
Common food additives
Studies have linked the presence of certain chemical compounds in pet food to problematic behaviors:
Artificial ingredients such as thickeners, binders, food colorings – lack of concentration, difficulty sitting still, fearfulness, and hyperactivity.
Preservatives such as BHA, BHT and Ethoxyquin – allergies, hyperactivity, neurotoxin – irrational fears, aggression, fearfulness and are highly linked to cancer.
Pesticides and chemical fertilizers from grain ingredients – aggression, irritability and they are considered as cancer causing agents.
In addition, the liver is responsible for filtering the toxins our dogs consume. According to Chinese medicine, once the liver can no longer control the quantity of toxins it receives, dogs will demonstrate behavior of fear and aggression.
Physical aspects
Many dogs suffer from allergies or sensitivities, either topical or digestive, which are connected to the food they eat. These manifest in symptoms such as itching, scratching, licking, excessive thirst, abdominal pain or cramping, nausea or loose stool. As a result, dogs become restless, irritable and hyperactive.
In order to handle these behaviors, we first need to tackle the base problem which is the sensitivity. Usually this is done by a food change.
In conclusion, nutrition has a great influence on your dogs behavior and mood. Some diets may cause him to be restless, aggressive and hyper, while others make him feel relaxed, content and easy to handle.
Once you know these dietary behavioral links, you will be able to spot if change is needed. A simple change in diet may improve not only your dog’s quality of life, but yours as well.
A proper diet for your dog should be one with quality protein, fresh vegetables and balanced complex carbohydrates. Of course, without artificial compounds and as close to his natural dietary needs as possible.
If you have any questions, you are welcome to contact me.
*this article was written for Wild at heart – Raw pet food delivery – https://www.wildatheartpets.com/ , http://www.facebook.com/WildAtHeartRaw/
References for nutrition and dog behavior
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Onnie J. Spring, Ph.D., Harris R. Lieberman, Ph.D., Geoffrey Swope and Gail S. Garfield, EFFECTS OF CARBOHYDRATES ON MOOD AND BEHAVIOR, Nutrition Reviews, Volume 44, Issue Supplement s3, Version of Record online: 27 APR 2009
Harju C. , Dietary Impact on Canine Behavior, Swedish University of Agricultural Sciences, pp. 4-9.
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Madras, B.K., Cohen, E.L., Fernstrom, J.D., Larin, F., Munro, H.N., Wurtman, R.J. (1973). Dietary Carbohydrate Increases Brain Tryptophan and Decreases Free Plasma Tryptophan. Nature, vol. 244, pp. 34–35
Dodman, N.H., Reisner, I., Shuster, L., Rand, W., Luescher, U.A., Robinson, I., Houpt, K.A. (1996). Effect of dietary protein content on behavior in dogs. Journal of the American Veterinary Medical Association, vol. 208, pp. 376–379