Home Dog Food 4 Most Dangerous Ingredients in Dog Foods (According to Science)

4 Most Dangerous Ingredients in Dog Foods (According to Science)


We already know that dog food can cost a pretty penny. While some people may associate higher cost of dog food with higher quality ingredients, one must really question this line of thinking. How many of the ingredients in your dogs food can you recognize, pronounce or understand?

The Most Dangerous Ingredients in Dog FoodsNot all dog foods are created equal, and expensive dog food brands certainly don’t always equal the best dog food ingredients. Unfortunately, there are pet food manufacturers, companies and brands out there that let the potential for profit overshadow the need for providing a high quality, wholesome and safe dog food.

As it has been uncovered in the huge list of pet food industry controversies, there are good reasons to question who makes our pets’ food and how they make it. Sadly, the responsibility must fall on the consumer, the dog owner, to ensure that the food they are feeding their dogs won’t do more harm than good.

Some suspicious parts that make up dog food are far more harmful than others, and there’s science to prove it. In this article, I’ll point out the four most dangerous ingredients in dog food so you can keep your eyes out for them. If you find these on the dog food’s ingredients list, it might be time to put down the food and switch brands.

READ: 31 Dog Food and Feeding Myths You Need to Stop Believing Right Now

4 Most Dangerous Ingredients in Dog Foods
(based on scientific research)

Most Dangerous Ingredients in Dog Foods

1 Unsafe artificial preservatives in dog foods

On a high level, consumers know that preservatives are used to well, preserve food.  However, what they don’t know is that preservatives are often used to increase the shelf life of the fats and oils within dog food. But as Sarah Taylor wrote in her top dog foods article, it’s one of the things to watch out for when picking the best dog food brand.

But not all preservatives are bad.

Natural preservatives do exist, too. Vitamins C (ascorbate) and E (tocopherol) are available and they are used. Natural preservatives are considered safe for dogs and humans, and that’s where the frustration sets in. Due to the slightly higher cost of raw natural ingredients, many dog food companies opt to use synthetic preservatives instead.

The first suspect is ethoxyquin.

Studies have observed the negative effects (1) of ethoxyquin several decades ago, yet it’s still being used in animal feed “because no alternative has been found yet.” Conclusionss from the study read:

“Toxicity and mutagenicity of EQ were observed in in vivo and in vitro studies showing its potential harmful effects.”

What is ethoxyquin, exactly?

The synthetic compound ethoxyquin is an artificial preservative used in dog foods that has been noted to increase the risk of toxicity in dogs, but that is not its only attribute. On top of that, ethoxyquin is also used as a pesticide.

Let that sink in for a moment:How pet food manufacturing industry works

A substance that is being used to effectively kill living organism is used as an additive for the canine that you hold dear to your heart.

Furthermore, ethoxyquin is also used in the rubber manufacturing process where it is seen as a hardening agent. The FDA has not let this go unnoticed and is currently investigating its role in the development of liver and blood complications.

Australia and the EU (European Union) has taken it a step further, and banned its use in dog foods outright. Next time you head to the pet store or grocery store looking to buy dog food for your pooch, check to see how many include this truly horrifying product. You will be surprised and appalled.

Prolonged feeding of food containing ethoxyquin has been shown (2) to lead to liver cell death, with the following symptoms; decrease in physical activity, reduced urination activity, brown-colored urine (a clear sign that something is wrong with the liver or kidneys) and pale gums (which is indicative of bad circulation).

There’s more than just ethoxyquin, however.

While ethoxyquin is currently under investigation and has been in the news as one the first ingredients to remove from animal feed, some other preservatives are still flowing freely into our dogs’ foods.

Another set of preservatives in dog foods to be wary of are the BH brothers, already well-known to many dog owners and cat owners alike: BHA (butylated hydroxyanisole) and BHT (butylated hydroxytoluene).

This one-two combination from hell is so bad that the WHO (World Health Organization) and the State of California has labeled both as being “suspicious cancer-causing compounds”, also known as carcinogens.

However, just like ethoxyquin, both BHA and BHT can still be found in many commercial dog food brands and are yet to be properly investigated by the FDA/CVM and removed.

Another one to note is the propylene glycol.

Propylene glycol (PG) may sound familiar to people, and that’s because most know it by its street name, anti-freeze. And, just like the other compounds previously discussed, it is shockingly added to dog food to preserve fats and oils that many dogs find delicious.

Just because it may taste good for the dog, doesn’t mean it is good for their body. In high doses, propylene glycol destroys erythrocytes (red blood cells), according to this study (3).

Another study with cats found (4) that propylene glycol causes anemia in animals among other problems, and is not a safe preservative to use in pet foods. From the study:

“These results indicated that PG cannot be considered innocuous even at concentrations consumed by cats eating commercial diets.”

RECOMMENDED: How Commercial Dog Food Is Made?

Radioactive looking dog food treats

2 Artificial colors and coloring agents in dog foods

As a rule of thumb, if it looks unnatural then you’re probably correct. Real dog food is not supposed to be radioactive yellow or fluorescent red in color.

It has been observed that dogs consuming food with a lot of artificial coloring will take up those color compounds into their gastrointestinal tract, according to this study (5).

Brilliant Blue FCF, or Indigotine, another artificial color, has been shown to inhibit the growth of dogs. The dogs eventually died of intercurrent virus infections, which is theorized to have been the result of a decreased ability to fight off the infection due to the dogs compromised health. Finally, there is evidence to suggest that regular intake of Indigotine may lead to the development of cancer (6).

The bright red dye known as Ponceau SX is a synthetic dye that when included in dog chow at a 2% concentration has led to the death of three of five dogs in a five-year clinically controlled study (7).

In the same family of dyes as Ponceau SX, Ponceau 3R has shown that including it in a dogs diet can have deleterious effects on the canines liver after a mere 32 weeks of feeding, according to this study (8).

ALSO READ: 16 Things You Didn’t Know About Prescription Dog Food

Most Dangerous Ingredients in Dog Foods

3 Rendering and rendered fat in dog foods

Only in the dog food business can the conversion of waste animal tissue be spun into a good thing. Dog food companies will proclaim that their inclusion of rendered fat into dog foods poses significant value for the owners and the dogs.

When has the addition of waste tissue ever translated into a value-add?

When animals are processed at the abattoir, lean cuts of meat are usually separated from the fats of the animal. This fat along with oils and other animal products (as well as any form of fat that producers can get their hands on from deep fryer grease to offal) are then heated and “purified” into lard or tallow.

Rendered fat is usually mixed into dry dog food for moisture, but also to make the meal palatable for the dog.

It has been observed that when oils and fats are listed as one of the first four in a dog foods ingredients list (meaning that there is a significant amount of it in the food) then there is a high probability that the dog will experience gastrointestinal (9) complications.

Not all fats are bad, however.

Animal matter that is usually consumed by dogs contain both proteins and fats. However, it has been shown that when these natural fats are replaced with rendered fats, the dog demonstrates a host of negative reactions. Loss of appetite, hair thinning and loss, skin lesions, ulcers and illnesses follow shortly after.

SIMILAR: How to Know Which Dog Food Is Good for Your Dog

4 Animal by-products in dog foods

Animal food waste used in pet foodsBy-product is the term given by the industry to all parts of an animal that is not muscle tissue. Understandably, this is a long list of miscellaneous body parts, organs, tissues and the like, and include beaks, hooves, tails, hair, bone, gills, eyes, teeth. It can also include some truly horrifying things such as diseased tissue and tumors.

Yes, you read that correctly – tumors. Chew on that thought the next time you pick up a bag of kibble or chow and see the it includes chicken, beef, pork, lamb or fish by-products.

The confusing thing is that dogs can digest animal by-products. Give a dog a chicken carcass and it will eat it to its hearts content. However, dogs were never meant to subsist on high concentrations of animal by-products the like of which are found in common commercial dog food and cat food brands.

While the by-products can be digested, there is significant variability in the total tract digestibility data – the digestibility of a substance throughout the entire process from entrance to exit – according to research (10).

This may not seem like a big issue, indeed it isn’t for the dog food companies as they keep on using animal by-products, but these variations should never and would never exist were a dog given a nutritionally complete diet.

Animal by-products are not used in the production of commercial dog food because of their nutritional value. They are used because of one thing and one thing only – they are cheap fillers.

The economics of the dog food industry states that using by-products as fillers pet foods will yield higher profit margins. That’s it! Never was a dog’s health and nutrition been in the minds of those that made this decision, and it shows.

By-products, while digestible (easily broken down), are not so easily absorbed into the dogs system. This is unsurprising as parts like beaks, hair and gills are very difficult, if not impossible, for a dogs body to convert into usable material (11).

RELATED: 3 Common Canine Diseases Linked To Dog Food

Take Home Message

Most Dangerous Ingredients in Dog FoodsIt’s clear to dog owners and manufacturers alike that many of today’s commercial dog food brands – some of which are very popular among pet owners – contain controversial and questionable, potentially dangerous ingredients that may be, and sometimes even proven to be, toxic to dogs.

With ingredients like ethoxyquin (a known pesticide), indigotine (a likely carcinogen), waste animal tissue and spare or diseased animal parts being included into dog food, one must really wonder if dog food manufacturers care for the health, safety and well-being of dogs.

Sure, their marketing and advertisements talk a big game and their talking heads proclaim that they exist to better the lives of dogs. But, the evidence in their ingredients suggest otherwise, and there’s scientific research to support this conclusion.

In general, when buying dog food, make sure to understand pet food labels, be wary of companies that prioritize advertisements and marketing campaigns, because you know that they aren’t using those funds to research or purchase higher quality ingredients.

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