Advanced Glycation End Products in Dog Food: Does Cooking Method Affect Your Dog's Health?
We spend a lot of time looking at what is in dog food: the protein, vegetables, fats, carbohydrates, vitamins and minerals. But there is another question I think deserves more attention: What happened to those ingredients before they reached your dog's bowl?
Grinding, extrusion, retort canning, drying, roasting and other forms of heat processing can change food. One of those changes involves the Maillard reaction and the formation of compounds called advanced glycation end products, or AGEs.
AGEs are one reason I care about cooking method and processing — but they are not a reason to panic over every piece of cooked food or assume that one format is automatically perfect and another automatically poisonous.
The newer canine research is actually more interesting than that.
AGEs in Dog Food: The Quick Answer
Advanced glycation end products are compounds that can form when sugars or other reactive carbonyl compounds interact with proteins during the Maillard reaction. Heat processing can encourage this chemistry, although AGEs also form naturally inside the body.
Research in dogs shows that different pet-food processing methods can produce very different AGE profiles. Importantly, it is not as simple as saying “kibble has the most AGEs.” In recent studies, wet/retorted foods had some of the highest levels of measured AGEs, while fresh foods showed advantages in available lysine and certain heat-derived compounds.
My takeaway is not that you need to memorize CML, CEL and methylglyoxal before breakfast. It is that how food is made changes the food — and that belongs in the nutrition conversation.
What Are Advanced Glycation End Products?
AGEs are a diverse group of compounds formed through a series of chemical reactions involving sugars or reactive carbonyl compounds and amino groups in proteins.
One pathway is the Maillard reaction — the same broad chemistry responsible for many of the flavors, aromas and browning we associate with cooked foods.
The Maillard reaction is not automatically evil. Humans have been browning food for a very long time, and your dog's lightly cooked turkey is not suddenly toxic because it saw a stove.
But with greater heat, time and certain processing conditions, more advanced reaction products can develop.
Two of the AGEs commonly measured in pet-food research are:
- CML — Nε-carboxymethyllysine
- CEL — Nε-carboxyethyllysine
Researchers also study reactive compounds such as glyoxal and methylglyoxal that can participate in AGE formation.
AGEs Don't Only Come From Food
Your dog's body also forms AGEs naturally.
Glycation occurs when sugars or reactive carbonyl compounds interact with proteins, fats or other biological molecules. Age, oxidative stress, blood-sugar regulation and metabolic health can all influence endogenous AGE formation.
So when we talk about “AGE exposure,” there are really two conversations:
Dietary AGEs
Compounds already present in foods before the dog eats them. Processing method, ingredients, temperature, moisture and cooking time can influence how much is formed.
AGEs Formed in the Body
AGEs can also develop through normal metabolism. Formation may increase with aging, oxidative stress and metabolic dysfunction.
That is why I don't treat this as simply a “kibble toxin” conversation.
What Does the Research Actually Show About AGEs in Dog Food?
This is where the story becomes more nuanced than some of the headlines.
A 2024 Study Compared Four Differently Processed Dog Diets
Researchers studied healthy dogs eating four food formats:
- canned wet food,
- extruded dry food,
- air-dried food, and
- mildly cooked fresh food.
The wet food contained the highest total dietary AGE concentration in that study and produced higher total plasma AGE concentrations than the other diets.
The relationships were not identical for every AGE measured. For example, urinary CML was higher with the dry food than with the wet and mildly cooked foods.
This is why “more processed = automatically more AGEs” is too simplistic. Different processing methods create different heat histories and different Maillard reaction products.
Then a 2026 Study Looked Directly at Commercial Dog Foods
A newer study compared 41 commercial dog foods, including fresh, kibble, wet, freeze-dried and cold-pressed foods.
Two findings caught my attention.
First, the measured advanced glycation end products CML and CEL were highest in the wet foods tested.
Second, the fresh foods had substantially more available lysine and less lysine blockage than kibble.
The fresh foods contained about 56 g/kg dry matter of lysine, compared with about 23 g/kg in kibble. Lysine blockage was also lower in the fresh foods than in kibble.
Reactive α-dicarbonyl compounds such as glyoxal and methylglyoxal were also substantially higher in wet foods than fresh foods.
That tells us something important: processing can affect both the compounds formed in the food and the nutritional availability of what was already there.
Why Lysine Deserves Part of This Conversation
Lysine is an essential amino acid. Dogs have to obtain it through food.
During the Maillard reaction, lysine can react with sugars and become chemically modified. A laboratory analysis may still detect nitrogen and protein, while some of that lysine is no longer available to the dog in the same way.
This is one reason I don't look only at the crude protein number on a bag of dog food. The amount of protein and the nutritional quality and availability of that protein are not exactly the same question.
If you want to dig further into what those dog-food labels really mean, read What's the Best Dog Food Kibble?
Does This Mean Canned Food Is Worse Than Kibble?
Not automatically.
This is where I don't want one interesting laboratory measurement to become the new dog-food religion.
Wet food brings moisture. Ingredients vary wildly between brands. Protein quality, carbohydrate load, fats, additives, digestibility and the dog's individual health all still count.
What the AGE research tells us is that retort processing can produce substantial heat-derived compounds even though canned food is moist.
Moist food does not automatically mean minimally processed food.
And dry food does not automatically contain the highest amount of every AGE.
Does This Mean Air-Dried and Freeze-Dried Foods Are Automatically Better?
No.
Processing labels are becoming marketing terms of their own.
“Air-dried,” “cold-pressed,” “freeze-dried,” “gently cooked” and “fresh” tell me something about how a product was made, but they do not tell me everything about the finished diet.
Temperature, duration, moisture, ingredient composition and the exact manufacturing process all influence the chemistry.
I still want to read the ingredient list, evaluate the fat, look at where the protein is coming from and decide whether the finished food actually fits the dog.
So Why Do I Still Prefer More Fresh Food?
Because AGEs are only one piece of a much larger nutrition picture.
Fresh and thoughtfully prepared food gives me more control over:
- ingredient quality,
- protein sources,
- fat quality,
- moisture,
- cooking method,
- dietary variety,
- nutrient density,
- and how the recipe is adjusted for the individual dog.
The newer research showing better lysine availability and lower levels of several heat-derived compounds in fresh food gives me one more reason to keep moving the bowl toward real food when it is practical.
It is not the only reason.
I don't feed fresh because one laboratory marker told me to. I feed more fresh food because the whole nutritional picture makes sense to me: better ingredient control, meaningful moisture, variety, quality protein and less dependence on a shelf-stable product that has had to survive substantial processing.
But What If My Dog Eats Kibble?
Improve the bowl you have.
I am not interested in making dog moms feel guilty because they cannot suddenly cook fourteen balanced meals on Sunday afternoon.
If kibble is what works for your household today, you can still:
- choose a better-quality kibble,
- add fresh animal protein when appropriate,
- add moisture,
- include fresh vegetables and whole foods,
- rotate proteins and foods thoughtfully,
- pay attention to fat freshness and storage,
- and gradually increase the percentage of fresh food if that works for you and your dog.
It does not have to be all kibble or all homemade.
Cooking Method Changes the Food Too
If you prepare food at home, you still have choices in how much heat you use.
In general, I prefer cooking methods that use moderate temperatures, moisture and only as much cooking time as we actually need.
| Cooking Method | How I Think About It |
|---|---|
| Light steaming | One of my favorite ways to soften vegetables without browning or exposing them to prolonged dry heat. |
| Poaching / simmering | Moist heat and moderate temperatures can be useful for gently preparing proteins. |
| Slow / gentle cooking | Can work well when temperatures remain moderate. Cooking time still counts, so “slow” does not automatically mean chemically unchanged. |
| Sous vide | Lower controlled temperatures can reduce heavy browning while cooking food consistently. |
| Roasting | Useful for some foods, but I generally cook only until tender rather than heavily browning or charring. |
| Grilling / frying / charring | High dry heat and heavy browning drive Maillard chemistry much harder. These are not my preferred everyday preparation methods for a dog's food. |
For more practical preparation guidance, see How to Prepare Vegetables for Dogs .
Do AGEs Cause Inflammation and Disease in Dogs?
This is where I want to distinguish biological plausibility from a claim we have actually proved in pet dogs.
AGEs can interact with receptors known collectively as RAGE. This signaling is involved in oxidative stress and inflammatory pathways and has been studied extensively in aging, metabolic disease, kidney disease, cardiovascular disease and neurodegenerative disease.
That does not mean we can look at a dog with arthritis, kidney disease or cognitive decline and say:
“AGEs in the kibble caused this.”
Canine dietary AGE research is still developing.
What we can say is that dogs absorb dietary AGEs, different food-processing methods influence AGE exposure, and the biological pathways are relevant enough that researchers are actively studying the health implications.
I don't need to prove that one molecule in one bag caused one diagnosis before I decide that reducing unnecessary processing and feeding more nutrient-rich fresh food is a reasonable goal.
Which Dogs Make Me Think More About AGE Load?
There is no symptom that tells me, “this dog has too many dietary AGEs.”
Itching, stiffness, diarrhea, cognitive changes or abnormal kidney values are not an AGE diagnostic test.
I am more interested in the dog's overall metabolic and inflammatory picture.
I may think more carefully about processing and AGE exposure in:
- senior dogs,
- dogs eating the same highly processed food for many years,
- dogs with diabetes or poor blood-sugar regulation,
- dogs with kidney concerns,
- dogs carrying significant chronic inflammatory burden,
- dogs with little dietary variety,
- and dogs whose overall diet is dominated by heavily processed foods and treats.
That does not mean AGEs caused the dog's condition. It means there may be little benefit in adding more metabolic and oxidative burden when we have realistic ways to improve the food.
Senior Dogs Are an Especially Interesting Group
AGEs naturally accumulate with age, so the senior-dog conversation is particularly interesting.
A 2025 year-long feeding study followed 22 senior dogs eating either an extruded kibble or a fresh diet. The dogs eating the fresh diet showed lower serum advanced glycation end-product metabolites along with a number of other metabolic differences.
I find that interesting — but I would not treat one small study as the final answer. The study involved only 22 geriatric sled dogs and was funded by The Farmer's Dog, with several authors employed by the company.
I still think the data are worth looking at. I just want you to know where the data came from.
If you are feeding an older dog, see my Senior Dog Nutrition guide for the much bigger food conversation around muscle, appetite, hydration, calories and healthy aging.
Can You Detox AGEs From a Dog?
Not in the simplistic way this sometimes gets presented online.
I would not tell you that bone broth, charcoal, clay, mushrooms or a bottle labeled “detox” is going to sweep AGEs out of your dog's tissues.
AGEs are a diverse group of compounds. Some come from food. Some form inside the body. Some may circulate. Others can become incorporated into tissues.
So rather than chasing an “AGE detox,” I would focus on the things that make sense for long-term metabolic resilience:
- improving food quality,
- reducing unnecessary high-heat processing where practical,
- feeding antioxidant-rich whole foods,
- using appropriate omega-3 fats,
- maintaining healthy body condition and muscle,
- supporting healthy blood-sugar regulation,
- keeping the dog active at an appropriate level,
- supporting gut, liver and kidney health based on the individual dog,
- and reducing unnecessary overall inflammatory and environmental load.
That is much more useful to me than adding another powder because somebody said it “binds AGEs.”
The Whole Dog Still Changes the Food Plan
As a holistic pet health coach and canine nutritionist, I often look at much more than whether a food is labeled raw, fresh, kibble or gently cooked.
I want to know:
- the dog's age and breed,
- body weight and muscle condition,
- activity level,
- diet history,
- how much of the diet is fresh versus highly processed,
- protein and fat quality,
- appetite and digestion,
- stool history,
- medications and supplements,
- kidney and liver trends,
- endocrine and metabolic disease,
- inflammatory conditions,
- and what the dog is actually doing on the current food.
The goal is not to win an argument about food formats.
The goal is to feed the dog in front of us better.
What I Want You to Take Away From the AGE Research
I don't want you leaving this article terrified of browned turkey.
And I don't want you deciding one bag of freeze-dried food is automatically perfect because the front says “minimally processed.”
What I want you to understand is something much bigger:
Ingredients are only part of food quality. Processing changes food too.
Heat can create new compounds. Processing can alter amino-acid availability. Different manufacturing methods produce different nutritional and chemical results.
That is one more reason I prefer moving dogs toward more fresh, recognizable foods and gentler preparation methods whenever we reasonably can.
Not because one AGE study proved fresh food prevents disease.
Because the more we learn about food, the less interested I become in judging a diet by the guaranteed analysis on the side of a bag.
Frequently Asked Questions About AGEs in Dog Food
What are advanced glycation end products in dog food?
Advanced glycation end products, or AGEs, are a diverse group of compounds that can form through reactions between sugars or reactive carbonyl compounds and proteins. Food processing, especially heat treatment, can contribute to their formation. AGEs also form naturally inside the body.
Does kibble contain AGEs?
Yes. AGEs and other Maillard reaction products have been measured in commercial dry dog food. However, kibble is not necessarily the highest-AGE food format for every compound. Studies have found particularly high concentrations of some measured AGEs in retorted wet foods.
Does canned dog food contain more AGEs than kibble?
In recent canine food studies, wet/retorted foods had the highest concentrations of several measured dietary AGEs, including CML and CEL. That does not mean every canned food is automatically worse nutritionally than every kibble. It does show why processing method deserves consideration alongside the ingredient list.
Is fresh dog food lower in AGEs?
Recent research found fresh foods lower in several heat-derived compounds than wet foods and found substantially greater available lysine and less lysine blockage in fresh food compared with kibble. Results vary depending on which AGE or reaction product is measured, so I would not reduce the research to one universal ranking.
Is gently cooked dog food better than kibble?
Gently cooked food gives us the opportunity to use fresh ingredients, meaningful moisture and lower cooking temperatures, but processing method alone does not make a diet nutritionally complete or appropriate. Ingredients, formulation, nutrient balance, fat quality and the individual dog's needs still count.
Does cooking dog food destroy amino acids?
Heat does not simply destroy all protein, but processing can change amino-acid availability. Lysine is particularly susceptible to Maillard reactions and can become chemically blocked. A 2026 analysis found more available lysine and less lysine blockage in fresh foods than kibble.
Does boiling or steaming reduce AGE formation?
Moist cooking methods and moderate temperatures generally create less intense browning than dry high-heat methods such as grilling, frying or charring. Exact AGE formation still depends on the food, temperature and cooking time. For home-prepared dog food, I generally prefer gentle preparation rather than heavily browning ingredients.
Do AGEs cause inflammation in dogs?
AGEs interact with biological pathways involved in oxidative stress and inflammatory signaling, and dogs absorb dietary AGEs. However, canine research has not established that a particular amount of dietary AGE causes a particular inflammatory disease in an individual dog. The relationship is an active area of research.
Can I tell if my dog has too many AGEs from symptoms?
No. There is no specific set of everyday symptoms that diagnoses excess dietary AGE exposure in a dog. Joint stiffness, digestive problems, skin issues, kidney changes and cognitive decline have many possible causes and should not be attributed to AGEs simply because the dog eats processed food.
Can I detox AGEs from my dog?
I would not treat AGEs as though one binder or detox supplement simply removes them. A more useful strategy is reducing unnecessary dietary and metabolic AGE formation, improving fresh-food intake, supporting antioxidant status, maintaining healthy blood-sugar regulation and supporting the organs and systems appropriate for the individual dog.
Should I stop feeding kibble because of AGEs?
Not because of one AGE study. If kibble is what works for your household, improve the quality of the food, add appropriate fresh foods and moisture, store it well and work toward more dietary variety where practical. Nutrition does not have to be all-or-nothing.
Want to Feed Better Without Turning Dinner Into a Chemistry Degree?
You do not need to calculate your dog's CML and CEL intake before making a better food choice.
If you are feeding kibble and want to improve the bowl, moving toward fresh food, or trying to build a diet around a health condition, we can look at what your dog is eating today and decide which changes are actually worth making.
Food format, protein, fats, processing, supplements, medical history, budget and what your dog will actually eat all belong in the same conversation.
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