Is Protein Lack Harming Your Dog?

Does your dog get enough protein in his diet? Chances are he does … but he can still suffer from protein deficiency.

Proteins are chains of little building blocks called amino acids. And your dog needs to get 10 of these essential amino acids in his food or his health will suffer. Many foods are high in protein, but don’t have the necessary amount of these critical amino acids your dog needs to thrive.

The resulting deficiency can cause problems with skin, hormones, growth and soft tissue. It can even cause behavioral changes. So getting the proteins right is pretty important.

So let’s take a look at how even raw diets can be deficient in protein … and what you can do to make sure your dog gets enough. But before we do, you need to understand just a little more about amino acids …

What Are Amino Acids?

Amino acids are the building blocks of proteins. They form chains and fold into three-dimensional shapes to form different proteins. Their final shape depends on their job. When your dog eats protein his body breaks it down into amino acids so it can absorb and use them.  

Proteins and amino acids are essential for all cells in every part of the body. It’s one of the major macronutrients, along with fat and carbohydrate and provides structure to the body. It helps form ligaments, tendons, bones, hair and nails. Amino acids also have many other important functions in your dog.

• Hormone control
• Enzyme activity
• Immune function
• Tissue growth and repair
• Metabolism
• Antibodies 
• Brain chemicals and mood
• Production of vitamins (B3)
• Brain, eye and heart function

So if your dog isn’t getting enough of the amino acids, his body won’t be able to function properly. 

There are 22 amino acids in total. All these amino acids are important to your dog and his cells, but 10 of them are essential. That means your dog can’t make them in his body, so he must get them through his diet. 

Essential Amino Acids

1. Arginine – Rids the body of ammonia, which is a byproduct of protein metabolism. It’s also a key component of proteins in the body. And it stimulates the release of hormones that regulate blood sugar and helps with cell signaling.
2. Histidine – Plays a key role in oxygen exchange in the lungs and tissues. Helps with tissue growth and repair and is a precursor for histamine, part of immune function.
3. Isoleucine – Helps form proteins in your dog’s body.
4. Leucine – Regulates the other amino acids in the body and protein synthesis. Also controls insulin levels and helps in the growth and repair of bones, skin and muscles.
5. Lysine – Found in collagen, which plays an important role in the structure of proteins and supports soft tissues. Also helps regulate cell metabolism.
6. Methionine – Used to make proteins and is required for protein synthesis and normal growth. Also helps regulate many enzymes, as well as cell division and growth.
7. Phenylalanine – Converts to tyrosine, a nonessential amino acid. It’s used for protein structure and is necessary for normal growth. Also helps regulate hormones, cell replication and signaling.
8. Threonine – Helps form proteins and tooth enamel, as well as collagen and elastin, which both help maintain soft tissue structure and elasticity. Control the activity of other proteins and enzymes. It also plays a role in immune health and the production of antibodies.
9. Tryptophan – Needed for normal growth and nitrogen balance. It’s also used to manufacture the hormone serotonin, which is a chemical messenger that can affect mood and heart function.
10. Valine – Required for muscle metabolism and tissue repair. It’s used as an energy source by muscle tissue as well.

The remaining 12 nonessential amino acids are all made in your dog’s liver.

1. Alanine
2. Asparagine
3. Aspartic Acid
4. Cysteine
5. Cystine
6. Glutamine
7. Glutamic Acid
8. Glycine
9. Hydroxyproline
10. Proline
11. Serine
12. Tyrosine

You may also hear taurine included as a nonessential amino acid. It isn’t used to make proteins and floats freely in the tissue. And technically taurine isn’t an amino acid because it has bonds that behave differently than other amino acids. But like amino acids, it does play a key role in most organs and helps with:

• Brain health
• Heart health
• Eye health
• Immune function
• Healthy blood
• Reproduction
• Immune health 

To make everything a bit more confusing, sometimes nonessential amino acids can become essential. I’ll give an example of that in a bit. But first, let’s look at what happens to your dog if he’s missing any of these essential amino acids.

Signs Of Protein Deficiency In Dogs

The symptoms of a protein or amino acid deficiency will depend on which amino acids your dog is missing. But the most common signs include:

• Reduced growth rate and milk production
• Poor coat, skin and bristle hair
• Anorexia (weight loss) 
• Anemia (lack of healthy blood cells)
• Change in mood
• Not All Proteins Are The Same
• When your dog eats proteins, they’re broken down into amino acids. Your dog’s body absorbs the amino acids and uses them for their many different functions. 
• Your dog can get amino acids from animal and plant proteins. But not every protein your dog eats is a complete protein, which contains all the amino acids he needs in the right amounts. In fact, most aren’t. 
• So to figure out which proteins are better, you need to look at the biological value (BV). BV considers the number of different essential amino acids in the protein and the amounts of each. 
• All foods get scored according to their biologic value using a number between 1 and 100. If all the amino acids are present and in a high enough amount to be of value to your dog … that protein has a high biological value.
• If one or more of the essential amino acids was missing or they’re present in low amounts, then a protein would have a low biological value. And the biological value of any protein can only be as high as the amino acid that’s found in the smallest amount (called the limiting amino acid).
• Let’s take a look at the biological value of some common foods …
• Eggs … 100
• Milk … 93 (but don’t forget, a lot of dogs are lactose intolerant)
• Chicken … 79
• Fish … 76 
• Beef … 75
• Wheat gluten … 64
• Tofu … 64
• Rice … 59
• Oatmeal … 55
• Bread … 54
• Lentils … 50
• Wheat flour … 41
• You probably noticed that proteins from animal sources are much more complete than those from plant sources. If you’re feeding your dog grains, these incomplete sources of protein can start to cause amino acid deficiency in your dog. That’s because they’re quite low in the essential amino acids.