Compounds known as AGEs are found in varying amounts in pet foods. With these substances linked to some chronic diseases in people, should the focus be on reduction?
Advanced Glycation End Products, or AGEs, are compounds made when proteins or lipids are exposed to sugar. They become attached via a covalent bond, or ‘glycated’. There are many pathways for the development of AGEs. They can form in situ over days to months, or can be taken in via dietary sources.
AGEs in food
Dietary AGE formation tends to happen during cooking at high temperatures, with levels often higher in animal-based foods. However, this is not a simple formula, as decreased cooking times, the presence of acidic ingredients and inhibitor compounds can decrease AGE formation. Moisture is necessary for some reactions, but conversely, higher levels can be inhibitory.
Dietary retention is similarly complicated. Studies have shown varying levels of absorption and excretion, and factors such as the influence of ingredients, compound weight, anti-AGE factors, and interactions with other nutrients such as fiber are not yet thoroughly understood.
Compared against a human diet, the impact of a single food’s AGE content is multiplied in our pets who tend to eat the same food day-to-day. The average canine daily intake of certain AGEs on a metabolic body weight basis has been estimated to be over 100-fold that of humans, according to the estimations of a study.
What is the concern?
AGE compounds can impart flavors and colors to food. However, they have been implicated in chronic diseases in people, especially inflammatory and oxidative processes, such as in cardiovascular disease, diabetes and Alzheimer’s. The reactions can also reduce bioavailability of the original nutrient – a notable example is lysine, an essential amino acid. In addition, there is concern that these newly formed compounds can serve as a source of unexpected allergens. The potential ill-effects in pets are less well known, but the same concerns are also extrapolated to pet food.
Next steps: improving knowledge and reducing dietary levels
There are still many unanswered questions regarding AGE levels in pet foods. Filling these knowledge gaps may be simpler than addressing the overarching question: How do AGEs impact pet health? In vivo, the ability to study AGEs suffers from the same limitation as studying any single nutritional factor: the difficulty in assessing and controlling for all potentially confounding factors. However, it has been theorized that increased life span in mice with caloric restriction was related to reduced AGE consumption.
Although endogenous production remains a significant source of AGEs, reducing the dietary component is associated with lowered overall levels. As pet food production methods vary greatly in ways known to affect AGE production, such as temperature and time, it is logical to consider how this may affect levels in pet foods. While AGE content of individual ingredients has been examined, studies looking at AGEs in pet food have only begun relatively recently, with few studies comparing different types of pet foods.
More information needed
In one study from the University of Georgia, AGE levels were highest in a wet food, followed by an air-dried food, kibble and a gently cooked/raw diet. However, the wet diet was the only diet found to be statistically different. AGE type also varies between categories of pet food. For example, certain AGEs may be higher in kibble than wet and vice versa. Overall, higher AGE content in wet diets over extruded has been a relatively consistent finding, however, further studies are needed. In personal communications with a variety of pet food manufacturers, few companies reported testing for AGEs, and testing methods vary. In addition, examining AGE content on a caloric basis is needed to accurately estimate a pet’s overall intake.
Further information regarding AGE formation and absorption, their role in disease, and the best ways to reduce dietary contribution as well as overall body stores in our pets is needed in order to best guide pet diets.
As many pets suffer from obesity and overfeeding, ensuring pets are fed an appropriate amount would be a simple first step to reducing the AGE burden. Additionally, in the pursuit of healthier diets for our pets, considerations such as food safety, nutrient bioavailability, shelf stability, and patient-specific nutritional needs should not be overlooked.
The latest articles
Former Fressnapf CEO moves to sushi company
Johannes Steegmann takes on a new role as CEO of Cologne-based Eat Happy Group.
Thai pet food industry responds to address temporary US export ban
The US government has identified the country’s pet food as a product category that is potentially produced with child or forced labor.
Canadian insect protein player secures investment to boost production
Entosystem aims to add a second factory to meet the increased demand for insect protein in the pet food industry.
Weekly newsletter to stay up-to-date
Discover what’s happening in the pet industry. Get the must-read stories and insights in your inbox.