Why Hydrolyzed Protein Dog Foods might NOT Be the Best Choice for Your DOG
You might have seen a buzz about Hydrolysed dog foods but before sampling some, there are some important questions you should get answered. Primary to this are: Hydrolyzed proteins, what are they and are they necessary for specific dog?
The reason why we ask this is because of their effect on some essential amino acids. That is the process has been known to denature some of the critical proteins your dog gets, meaning that additional amino acids have to be added to dog food to make up for this!
In this article we also look at what alternatives there are to this (often) prescription dog food, that is a better solution to what the hydrolised protein is supposed to be solving.
If you want to understand the full universe of hydrolysed dog food, and why it commands the high price, please read all of the sections below. This is a complete and compact guide.
If you are just interested in the negative effects on essential amino acids and the alternatives in food, please view those specific sections. The following are the order in which we address this topic:
1 What are hydrolyzed proteins and hydrolysed dog food
2 HOW are hydrolysed proteins made?
3 WHAT are they supposed to fix for your dog?
4 What are the potential negative effects.
5 THE TECHNICAL effects on ESSENTIAL AMINO ACIDS
6 Alternatives to using hydrolysed proteins
1 INTRODUCTION
Did you know that Hydrolysed dog food is a ‘specialized’ diet created by dog food companies for dogs with food allergies, sensitivities, and some gastrointestinal conditions.
It might seem that this is a noble effort – but it doesn’t have anything to do with providing more meat for your dogs (or the quality protein and fats that meat and offal provides).
Instead, hydrolysed proteins, are proteins that are “broken down” into smaller components through a process called hydrolysis. This breakdown aims to reduce the likelihood of triggering an adverse immune response in sensitive dogs.
But as you will learn, there are important concerns about this end product too.
2 HOW are hydrolysed proteins made
Hydrolyzed dog food, is just regular dog food that is processed (several methods) to shorten the protein chemical chains.
Hydrolyzation is the chemical process where proteins break down the bonds in the amino acids into smaller chunks. Because the processes typically uses water to break the bonds it has the word HYDRO in it.
Breaking the amino acids apart makes smaller peptide chains and free amino acids. These smaller protein fragments are created and used because in theory they are less likely to be recognized by the dog’s immune system as allergens.
3 WHAT are they supposed to fix?
They have a potential to fix (or reduce the symptoms of) dog Food Allergies and Sensitivities:
If you dog doesn’t have food allergies, it DOES NOT NEED hydrolysed protein. For a regular dog, the process provides more negatives than positives.
Dogs with food allergies often react to specific protein sources (ie a specific meat or specific plant). Breaking down the proteins that they would normally react to (skin rash, itching, loose stools) – can (In theory) be reduced. But of course, not all of these serious medical conditions can be resolved by hydrolysed proteins alone.
Inflammatory Bowel Disease (IBD): This is a chronic condition in the dog intestine that results in inflammation of the gastrointestinal tract. The results can be excess gas and loose stools and inability to take up nutrition.
Exocrine Pancreatic Insufficiency (EPI):
Dogs with EPI have difficulty digesting food due to insufficient production of pancreatic enzymes causing difficulty in digesting food (in the stomach). The pre-digested nature of hydrolysed proteins makes them easier to absorb, benefiting dogs with this condition.
Note, EPI isn’t always caused by Protein sensitivity. It can be caused by Pancreatitis, cystic fibrosis and other conditions that affect the pancreas. The pancreas is a vital gland in the dog’s body. Malfunction can severely effect quality of life and longevity.
4 Negatives of hydrolysed diets for dogs
A major issue is their effects on ESSENTIAL AMINO acids and palatability, but there are other issues, and definitely food alternatives to use instead of relying on expensive hydrolysed products.
Below we will summarise some of the key negatives owners and dogs are finding:
A Cost: Hydrolyzed protein diets often come at a higher price point due to the “specialized” processing involved.
If your dog doesn’t have an issue that hydrolised can fix, or if they haven’t been 100% diagonised with a specific protein allergy, there is NO reason they should have a hydrolysed product.
Commercial dog food corporations have long understood that segmenting the market and adding a “specialised” label to dog food (food for specific breeds, or weight loss or a specific illness) can help them make a large profit over their already very healthy profits for regular kibble.
If you look through the ingredients list for any one brand of dog food, you will find that often the first five ingredients can be the same, but trace elements or the amount of one specific ingredient (like fibre) can be increased or decreased to fit the ‘purpose’ written on the pack.
The same goes for trendy food like Vegan (very bad nutrition idea) or hypo-allergenic, and now the new buzz word ‘hydrolysed’.
It doesn’t mean that for some dogs, they hydrolysed treatments don’t provide some comfort. However, universally you are going to be paying a higher price, for essentially what is a bag of grain or potatoes, versus actually feeding a dog meat that it isn’t allergic to. Or supplementing the kibble with REAL meat treats, that they are not allergic to.
The two previous articles on this site have discussed at length the value of quality protein for dogs (ie not plant matter) with MEAT having higher absolute amounts of essential amino acids and higher bio-availability (ie your dog can actually use them).
If you are under financial pressure from vet bills, dog insurance and commercial dog food, you might consider other natural food options that might be better for your dog, but more on that later.
B Palatability Issues:
This should be a concern for all dog owners. How many dog owners would eat the exact same meal for breakfast and dinner, with the occasional non meat candy thrown in? NONE.
Commercial dog food already comes with a stern warning about not changing kibble quickly from one brand to another (to ensure that people are scared to do so and it stops switching by many owners).
Yet, all texts say domestic dogs are in part scavengers (ie will eat random food of any time, on any day). Variety is the NATURAL thing that dogs thrive on, like humans.
It is known that many dogs find hydrolysed diets less palatable. That means they don’t like the taste of their primary meal (or the smell) and can lead to reduced food intake, and loss of nutrition.
The commercial dog food companies try to solve this issue by adding “Flavour enhancers” .
While this can be a complex chemical, often it’s just boosting the sugar, salt or fats in the ingredients list to fool the dogs into thinking they are eating something good. We wouldn’t think this was a great of fair thing to do to humans, nor should it be done to dogs.
3. Prescription Requirement:
If you are worried about the increased weekly shopping bill cost for hydrolysed products, consider that most “reputable” hydrolysed protein dog foods are available only by veterinary prescription in Australia and America.
NOTE if your dog has a food allergy, but it isn’t identified, using hydrolysed food isn’t SOLVING the issue your dog is having, its often merely masking the underlying cause and costing you twice. And your dog potentially more.
THE MAIN issue with hydrolysed proteins for dogs
Hydrolysed protein dog food undergoes a process that breaks down proteins into smaller peptides and free amino acids. But what does this practically mean for you?
The issue is how the process affects the availability and bioavailability of essential amino acids, which are critical for a dog’s overall health.
A quick recap: of the 20 amino acids available in food, dogs need TEN of these to do all their bodily functions. Humans Need 9 and cats need 11. If dogs don’t get sufficient essential amino acids, including limiting amino acids, in their food, in a useable format, then their health will have major negative impacts.
NOTE, the hydrolysis process is said to not remove or destroy the Essential amino acids but changes the structure of proteins.
- The two major benefits that meat and offal diets provide are exactly the two things that hydrolysed diets risk making worse for your dog – Palatability Issues!
The hydrolysis process can result in a bitter taste, as free amino acids tend to be less palatable. And because the food is unnatural to begin with (plant based for a carnivore), and then is processed further (hydrolysed) it can cause many dogs to not want to eat hydrolysed diets unless flavour enhancers are added.
This can lead dogs to more scavenger behaviour or less safe things in the house or park, or eating disorders. Or just generally less happiness in life.
- Potential Loss of Specific Amino Acids (this is a major concern)
Some hydrolysis methods involve heat or enzymatic treatments that may degrade sensitive amino acids like lysine and tryptophan.
You will know this has happened when you see the bottom of the ingredient list having ADDED amino acids (probably from plant matter – which is less bio-available but cheaper) to compensate for the loss of these critical amino acids to ensure that they meet the bare minimum requirements of the aafco tables.
How many dogs could benefit from hydrolised diets?
It is estimated that in Australia about 1-2 % of all domestic dogs might suffer from food allergies. Given the opportunity, most dog food companies would like to convert all of these dogs over to their higher margin hydrolysed product ranges.
5. THE TECHNICAL effects on ESSENTIAL AMINO ACIDS
The Hydrolysed processes involves Water, but it also involves heat, acid, or enzymatic treatments. THESE can affect specific essential amino acids in the following ways:
Essential Amino Acids Most Affected by Hydrolysis
- Lysine
- Highly sensitive to heat and Maillard reactions (interaction with carbohydrates).
- May become less bio-available if it binds to sugars (from the plant matter in the commercial dog food), forming an unusable complex sugar.
- What manufacturers do: supplement hydrolysed diets with free lysine.
2 Methionine & Cysteine (Sulphur-containing amino acids)
- Can have oxidation during hydrolysed processing, reducing the essential amino acid effectiveness.
- These TWO essential amino acids are VITAL for skin, coat health, and metabolism.
- What manufacturers do: Supplementation dog food with synthetic methionine as needed.
3 Tryptophan
- Is destroyed by extreme heat and acid hydrolysis.
- Tryptophan is needed for serotonin production (mood regulation) in your dog’s immune function.
- What manufacturers do: added back in free form.
4 Arginine
- Can be degraded by enzymatic hydrolysis .
- Arginine is critical for blood vessel function, immune response, and detoxification.
- What manufacturers do: Supplemented as a free amino into the packet
Overall Protein Quality
- Hydrolyzed proteins still provide all essential amino acids, but some losses occur, particularly in heat-sensitive amino acids like lysine and tryptophan.
6. ALTERNATIVES to hydrolysed diets
Not all dogs with food allergies are placed on hydrolysed diets.
This is the vet’s discretion.
A safer, cheaper, more natural approach taken by professionals is to manage food allergies with novel protein or limited ingredient diets.
A novel protein is one that a most dogs have not encountered before (is usually a meat protein to ensure they get sufficient quality protein), and is considered Hypo-allergenic. Such meats as kangaroo, fish and crocodile are examples.
Sometimes hydrolysed protein diets are prescribed just during elimination trials to diagnose the specific food allergies. This is where under a vet’s guidance, a dog is usually fed one novel meat and usually rice, with no other foods permitted during the 6-8 weeks.
They are testing to see if allergy symptoms improve. If they do, it’s likely that something in the original dog food diet was causing the allergy.
If they don’t improve it is likely that the allergy is caused by something else. Environmental allergies (like grass or a specific plant contact) or mites, or even something in the home like dust, is causing the allergic reactions.
Vets can also sometimes use a hydrolysed diet as a diagnostic tool. And that is probably the best use of it, rather than a long-term solution, where the owner never gets to find out actually what was causing the bad reaction.
This means that without specifying the protein causing issues, that any food or treats the dog might get at home or while at the park, can re-cause a bad allergy reaction.
It is worth noting that 20% to 30% of dogs with food allergies also have other existing allergies, known as concurrent allergies. Allergies such as plant contact or insects can cause similar allergic reactions to dog food allergies.
Of the 1-2% of dogs thought to have primarily dog food allergies, 75% of these food allergies are protein-related, 25% are related to carbohydrate-related allergies. The 75% of protein related allergies can be from meat or grain/ plant matter. Only elimination diets are likely to narrow down specifically which food protein is causing it.
CONCLUSION
To recap: the supposed benefits of Hydrolysed proteins, is that they are easier to digest since the body doesn’t have to break them down as much. The smaller peptides and free amino acids are more easily absorbed in the dog’s intestine, making them more bioavailable (particularly for plant matter).
This can be especially beneficial for dogs with digestive disorders, as it reduces the effort required for nutrient absorption.
Solving the CAUSE of the allergy reactions is VERY IMPORTANT.
But of course, MEAT PROTEIN is already HIGHLY BIO-AVAILBABLE. They don’t need to be processed in order for the dogs to find them both highly palatable and highly bioavailable.
Ideally vets would always recommend an exclusion diet first, but time and money are often against this most rigorous but accurate method, so they might offer alternative solutions.
Many vets sell hydrolysed protein kibble, and they also prescribe hydrolysed protein. If this works, the client will pay a premium for a tasteless food that has food enhances added just to make it taste palatable to their dogs.
Only 1-2 % of dogs have diagnosed food allergies, the ideal process would be to use an exclusion diet, but alternatively owners can provide Home based foods (single meat) and rice. They can add calcium and phosphorous (or provide chewable safe bones, and offal too.
It is often the grocery list of ingredients on any typical kibble pack, that disguises what food a dog is actually allergic to.
Hydrolysed proteins are expensive and do not solve the problem, just hide it.
Essential amino acids are the TEN amino acids in protein that dogs must get from food because they can’t make sufficient amounts in their body for normal functioning. They are ESSENTIAL to be healthy.
Of the TEN shown below, there are at least FOUR that can be negatively impacted (amino acids de-natured) by various hydrolysed processes. This means that the dog food manufacturers must add these specific ones (often from unknown sources) just to meet the minimum aafco requirements to be called dog food.
The essential amino acids potentially at stake are shown in red below.
- Arginine: Helps with muscle growth, blood pressure, and wound healing
- Histidine: Helps with tissue growth and repair, and the production of hemoglobin and histamine
- Isoleucine: Helps with muscle building, tissue repair, and blood sugar regulation
- Leucine: Helps with muscle growth and repair, and blood sugar regulation
- Lysine: Helps with growth and development, and the absorption of calcium
- Methionine: Helps with liver detoxification and tissue growth and repair
- Phenylalanine: Helps with brain health, appetite, mood, and behavior
- Threonine: Helps with immune system, digestion, and nutrient absorption
- Tryptophan: Helps with mood and sleep by producing serotonin
- Valine: Helps with muscle development, nerve function, and energy production
While hydrolysed dog foods, were in theory created to help dogs with specific diseases, there are many other more natural methods of solving the issues, including properly diagnosing what actual food a dog is allergic to.
In the process of making the hydrolysed proteins, FOUR of the TEN essential amino acids dogs need from food, are often reduced or de-natured.
This means replacement essential amino acids need to be added to the commercial dog food, and its highly likely that they are also from low bio-availability plant sources or artificial chemicals.
Even if a dog is on a hydrolysed diet, if you know that they are not allergic to a specific SINGLE INGREDIENT meat (beef, chicken, kangaroo, fish, crocodile, lamb etc) – then it safe to feed them these single ingredient dog treats (because you will know that they will only be reacting to the single protein in the single ingredient meat or offal product.
AND you will be providing the much-needed full range of essential amino acids to supplement the often relatively lower quality proteins that are available in commercial dog food or hydrolysed protein dog good.
REFERENCES
1 Effect of Maillard induced glycation on protein hydrolysis by lysine/arginine and non-lysine/arginine specific proteases – ScienceDirect Food Hydrocolloids. Volume 69, Y. Deng a, P.A. Wierenga a, H.A. Schols a, S. Sforza a b, H. Gruppen August 2017, Pages 210-219
2 Arginine metabolism and nutrition in growth, health and disease. Amino Acids Author manuscript; available in PMC: 2010 May 1. Published in final edited form as: Amino Acids. 2008 Nov 23;37(1):153–168. doi: Guoyao Wu , Fuller W Bazer , Teresa A Davis , Sung Woo Kim, Peng Li , et al
3 Reactivity and degradation products of tryptophan in solution and proteins. Author: Stephanie Bellmaine, Alisa Schnellbaecher, Aline Zimmer. Free Radical Biology and Medicine. Volume 160, 20 November 2020, Pages 696-718