Plenty of pet parents were scared stiff by the 2007 pet food recalls and by subsequent scares. Perhaps one good thing to come out of it was that more of us became focused on what we are feeding our dogs and cats and whether food is playing a role in their overall health.
But then the internet became flooded with contradicting information. On the one hand, the advocates for raw and home-cooked diets sing the health benefits for their animals. On the other hand, the pet industry is hitting back with an ever-increasing variety of pet food, boutique foods, and extensive marketing.
All of this has muddied the waters and made the answer more complex than we would like it to be.
But choosing whether or not to feed kibble to our dogs and cats is one of the big decisions we have to make as pet guardians. So, we need to know, is dry dog food good for dogs? Why might processed food be bad for dogs or cats? Do dogs need kibble? And finally, what can you feed your dog instead of kibble?
To answer these questions, we will look at the key points about dry food that you need to know as a pet owner.
Dry food and processed food vs. less processed food
Before we get into science, we can look at pet food through the same lens of common sense we can apply to our diets.
No, this does not mean your dog or cat doesn't have its own nutritional needs (they most certainly do), but certain principles in food remain the same for all mammals.
Dogs originally ate human leftovers in the 1800s, at a time when processed food did not exist. While cats are true carnivores, dogs are omnivores and have little problem digesting much of the plant material that we do.
How dogs came to eat kibble in the first place was a massive feat of marketing. It's a long story, but the key points are:
- The first commercial dog food was started by James Spratt in 1860, who refused to name the meat in his product. It was expensive and only marketed to the rich.
- Spratt used an aggressive marketing strategy to move pet lovers from feeding table scraps to his biscuits instead.
- Canned pet food was introduced in 1922 and mainly consisted of horse meat, carefully labeled "lean, red meat."
- Horse lovers and World War II created a shift in the pet food market. Suddenly, there was a need for pet food that was easy to keep, use, and had a long shelf life.
- General Mills and the Ralston Purina Company created the first kibble through the process of extrusion in 1956. This involved baking food at extremely high temperatures and removing all moisture.
- Soon new flavors and varieties were on offer.
- A series of ad campaigns left pet owners under the impression that kibble was the only proper way to feed one's pets. The concept of "dog food" as opposed to just "food" was born.
The story doesn't end there, but it briefly outlines how cat and dog food became highly processed and how we came to see this as normal. Much like our own move to processed food in the 60s and 70s, with the advent of Mcdonalds and shifts in our food supply chain, processing pet food became accepted.
It's only relatively recently that we began to understand the effects of processed food on our health. High sugar content, overloads of simple carbohydrates, low nutrient values, and high calories led to an explosion of obesity.
This was quickly followed by related health issues such as diabetes, heart conditions, and high blood pressure.
Similarly, we have only now begun to consider that highly processed pet food might have the same consequences for our dogs and cats.
Is dry food really "complete and balanced" with all your dog's essential nutrients?
Pet food packaging typically claims that it is completely balanced with all your pet's nutritional needs. Because of this, most of us give our pets that same food, day in and day out, believing that we are meeting all our pet's basic nutritional requirements.
For pet food to label itself "complete and balanced," it needs to meet the basic minimal and maximum standards for nutrients prescribed by the Association of American Feed Control Officials (AAFCO). The AAFCO guidelines stipulate standards according to a pet's age and reproductive stage.
While adhering to AAFCO guidelines is important, since it is better than no guidelines, there are many criticisms. These include:
- The organization is extremely slow to change its guidelines according to new research. In fact, current guidelines date back to 1995.
- AAFCO guidelines are incomplete. For example, although the importance of omega-6 and omega-3 fatty acids in a dog's diet are widely recognized, they are not included in AAFCO's standards.
- Some maximums allowed can be toxic in such high doses. These include iron and copper. Nevertheless, the guidelines aren't changed due to concerns over bioavailability and a lack of research.
Finally, the AAFCO guidelines are extremely sympathetic to the pet food industry's current state, which means they overlook certain problems.
For example, the process of extrusion and baking dry food like kibble at extremely high temperatures has several dire consequences for the food. In fact, the protein in dry foods is cooked twice, first during rendering and then during extrusion.
Research shows that extrusion:
- Lowers the quality of the protein, called the Maillard Effect.
- Decreases palatability
- Causes a loss of heat-sensitive vitamins
- Scorches the starch in the food, causing the release of free radicals and carcinogens
To make up for the loss of nutrients, most kibble manufacturers add vitamins and minerals after the extrusion process. This is similar to how cereal manufacturers often put vitamins and minerals in over-processed, high-sugar cereals.
The fact remains that those same vitamins and minerals are better accessed through fresh and whole foods.
Does dry food cause disease?
Dry dog kibble can and often does cause disease. Aside from the frequent recalls such as those in 2007, where pet food becomes contaminated, there are many other ways that kibble can affect your dog's health.
- Proteins that are "denatured" during extrusion may contribute to food intolerance, allergies, and irritable bowel syndrome.
- The process of cooking starches as a binding agent in kibble leads to the release of the carcinogen acrylamide. While this may not make a difference in the short term, dogs and cats who eat these free radicals every day for years may be more prone to developing cancer.
- Studies have revealed considerable levels of mycotoxins in extruded dry dog food. Mycotoxins are a by-product of fungi that may be entering dog food through bad quality grains prone to mold. They are known to cause disease in both humans and animals. However, studies are needed to determine precisely how frequent exposure to mycotoxins in pet food may be affecting our pets.
- Some preservatives in our kibble, such as butylated hydroxyanisole (BHA) and butylated hydroxytoluene (BHT), are known carcinogens and are still permitted in small amounts.
Other areas for concern involving kibble involve bacterial contamination from slaughtered animals, fertilizer and pesticide residue, and GMO ingredients.
The problem of high calories and low nutrients in dry food
In research dating back to the 1960s, Dr. Roy Walford established that limiting caloric intake and maximizing nutrition was the secret to longevity in mice. Studies since have backed up this claim.
Nevertheless, we don't always extend this advice to our dogs. Even specialized home-cooked diets are often too high in calories for our animals' needs. However, the problem of high calories and low nutrition is compounded in dry dog food.
We have established that the processing of kibble reduces the number of nutrients naturally available in the food: meaning, the kibble then has to be fortified to have the nutrients replaced.
But it also means that all the ingredients are ground down. Like our own junk food, what once made the ingredients nutritious has been reduced to empty calories. The fiber, the quality protein, the original nutrients, are all removed in the extrusion process, but the calories remain.
This in itself is a problem. In fact, nearly 60% of cats and 54% of dogs in the United States are classified as overweight or obese.
Among the health problems, obesity is linked to is also diabetes.
Although there is no research that can directly blame kibble for diabetes in cats and dogs, the simple carbohydrates in kibble can cause spikes in blood sugar and may not be the best choice for diabetic dogs.
Bioavailability and nutrient absorption in dry food
Feeding the same food day and day out can interfere with nutrient absorption and the bioavailability of certain minerals and vitamins.
As kibble is fed as a "complete and balanced" diet, every meal is with the same ingredients, cooked in the same way, regardless of how one nutrient may affect the absorption of another.
This is not a topic that has been adequately researched. But it is one reason AAFCO allows maximums in nutrients such as iron or copper that may be toxic to dogs.
One example of why this may be problematic is the effect of calcium on the absorption of iron. A study on rats and dogs found that giving dogs calcium simultaneously as iron that was not protected by a layer of vitamin C inhibited iron absorption by 50%.
Therefore, feeding a diet that doesn't separate calcium from iron by at least an hour can inhibit iron absorption, possibly leading to a deficiency, even if the food meets the AAFCO standards for minimums of both calcium and iron.
Lack of moisture in dry pet food: why is it a problem?
The lack of moisture in kibble can also have a toll on the health of your pet. Overall, there is only about 5 – 10% moisture left in dry food. This means that for your pet to digest it, they need to draw on moisture from their own organs, particularly the kidneys, liver, and skin.
Therefore, just digesting dry kibble can cause dehydration and put pressure on your pet's organs.
Dry food is particularly problematic for cats, which evolved in arid regions like Egypt. Because of this, they developed a digestive tract where most of their moisture comes from their food. After all, eating live prey means eating food that is about 80% moisture.
Cats need to compensate for the lack of moisture in dry food by drawing on their kidneys. In the long term, this may lead to urinary tract problems and even renal failure.
The problem of misleading labels
Further problems involving pet food also involve the issue of misleading labels. While the FDA has banned the use of 4-D meat (meat from diseased, dying, dead, or destroyed animals) in pet food, there is still an overall lack of regulation and oversight over what actually goes in a bag of kibble.
In general, an ingredient list of more than ten ingredients is a red flag for kibble. And the first seven ingredients are the most important. These should consist of whole, named meat, whole vegetables, and grains.
Beware of so-called "BEG" diets. That is boutique, exotic ingredients, and grain-free kibble. Recently, grain-free dry food has been linked to canine dilated cardiomyopathy (DCM).
While this is still under investigation, these diets tend to be nothing more than marketing gimmicks that add ingredients with no real benefit for your pet but tend to push the price up.
Low-quality ingredients are another issue.
Unnamed meats or partial grains such as "meat by-product meal" or "corn-gluten meal" are indicators of food that is not fit for human consumption. They are probably of little nutritional value for your pet, if not downright dangerous.
Labels also need to be scanned for artificial preservatives, flavorings, colorants, and fillers.
Can I still feed my pet kibble? Alternatives and how to improve a kibble diet.
Despite what has been discussed in this article, there are still reasons why kibble is the most popular form of pet food. These include:
- It is convenient, as there is no preparation involved
- It has a long shelf life
- In general, it is cost-effective and cheaper than many other diets
- It has a reduced risk of bacteria.
Nevertheless, there are alternatives. For example, non-extruded dry foods, such as those that have been air-dried, often compete in price and are just as convenient as kibble. The main difference being, they have maintained most of the nutritional value as they are cooked in normal pressure environments on a slow heat over a longer period of time.
What can you do to improve a kibble diet?
However, if you are forced to feed kibble, you can still improve your pet's diet quality. One can still provide a diet that is partially made up of kibble and partially of whole or fresh foods.
A high-quality kibble can be supplemented with about 15% of fresh ingredients.
You can top up their kibble with eggs, quality meat, or fish, or give it to them in the form of treats. You can also make use of Pet Assistant's algorithms to pinpoint the best diet for your dog, given your budget, or book an appointment with a nutritional expert that can guide you through your food choices.
While further research is needed, kibble may not be the best diet for most pets. The extrusion process removes most of the nutrients and brings out potential causes of disease such as carcinogens and mycotoxins.
While kibble is often cost-effective and convenient, there are a number of great, cost comparative alternatives available on the market. In the case where you need to feed kibble, consider adding fresh food to upgrade your pet's diet.