Additives in the Diet?
Food additives are not strictly part of the nutrients of the diet. However, as noted by Dr. Shawn Messonnier, additives can include a number of substances, such as chemical preservatives, artificial colouring, and artificial flavours.
"Any food that requires enhancing by the use of chemical substances should in no way be considered food"
~ John. H. Tobe
Preservatives are essential in preventing spoilage of food. As people learned more about food and as chemicals were developed to prevent spoilage, the incidence of food poisoning statistically decreased. However, chemicals also have a bad side. Long-term ingestion of certain chemicals might be harmful and may be linked to chronic disease including cancers. Purists try to avoid man-made chemicals in diets fed to pets.
The following information is meant as a general guideline, and has been researched from other sources.
However, it is important that pet parents not totally abandon preservatives or they risk causing illness in pets due to food poisoning. Some manufacturers of pet foods have responded to the preference to move away from chemicals and include more natural preservatives. When choosing commercially prepared diets, antioxidants such as vitamin E and vitamin C have replaced chemicals such as ethoxyquin , butylated hydroxyanisole (BHA), and butylated hydroxytoluene (BHT).
BHA, BHT, and ethoxyquin are chemical antioxidants designed to extend the shelf life and reduce fat spoilage (rancidity) of pet foods and pet treats. Chemical additives and artificial preservatives such as BHA, BHT, and ethoxyquin may cause dry skin, allergic reactions, dental disease, and poor health, as well as stimulate adverse effects on liver and kidney functions.
Specifically, BHA, and BHT, are both artificial preservatives added to oils to slow down deterioration. BHA and BHT (as well as ethoxyquin) are used in numerous pet food brands, including both "premium-grade" brands, to replace vitamin E, which is removed during oil processing. Studies have shown that BHA and BHT promote liver disease and other medical problems [BHA — A Time Bomb in Your Dog’s Food?] [ref] [These Dog Food Preservatives Could Be Toxic to Your Pet] [ref].
Careful reading of the label will inform pet parents what chemicals, if any, are added to the pet’s food. Frozen biologically specie appropriate raw foods are therefore typically deep frozen, and we always suggest thawing in the freezer, as it is almost impossible to formulate natural raw cuisine that are resistant to spoiling, however, the cuisine we supply to you and your fur kids contains no chemicals.
Artificial colours and flavours are really not necessary in pet foods, but still make their way in to appease the pet parents. Because dogs and cats don’t have the colour vision of people, they don’t care about the colour of the food you choose. Colours are added to be more attractive to pet parents, who must make purchase decisions regarding the large number of foods available to them. Artificial flavours should not be needed if the food is palatable. Whenever artificial flavours are added to foods, pet parents should question whether the fur kids would eat the food without the flavours. If the fur kids would not, one has to wonder why the pet parent would choose to purchase that food!
Emulsifiers, Gellers and Thickeners
As noted by Dr Ron Hines [ref], we already know that a typical can (wet) cat or dog food is about two-thirds (~78%) water. That appears to be about the maximum the commercial pet food producers can conceal in their products. Commercial pet food manufacturers know that pet parents perception is everything and that you wouldn’t be happy if you opened the can and saw that the top two-thirds was water. So they add emulsifiers to distribute the water evenly, and jellying products to thicken it up, another set of additives we need to be aware off.
However, there is a growing body of evidence that these emulsifying / thickening products have the potential drastically alter the type and number of bacteria found in your pet’s intestine [Systemic Responses of Mice to Dextran Sulfate Sodium-Induced Acute Ulcerative Colitis Using H NMR Spectroscopy][ref] (requires Adobe PDF Reader). They are also thought to have the potential to encourage inflammatory bowel disease by stripping the pet’s intestinal wall of its protective mucus layer. That allows bacteria and other pet food ingredients to have a much closer position to your pet’s immune system cells – forcing the system to make snap decisions regarding the many potential food antigens pet foods contain [Dietary emulsifiers impact the mouse gut microbiota promoting colitis and metabolic syndrome] [ref] (requires Adobe PDF Reader). Some of these additives are irritating in their own right.
Commercial pet food manufacturers and their fellow travellers will reply that all these additives have been approved by the FDA (that is the US Food & Drug Administration). That is true. However, most of those studies were done long ago, long before the rise in intestinal inflammation problems occurred and before scientists had any knowledge of how the immune system’s memory functioned.
The most common emulsifiers / thickeners in canned pet foods are carrageenan, cassia gum, guar gum, cellulose gum / (aka carboxymethylcellulose), and xanthan gum that you might see on the ingredient labels. The kelp and saccharina are probably added to perform a similar thickening function – not because of any known healthful effects in dogs or cats.
In one study, carrageenan, at least in the presence of other cancer-causing agents, was thought to accelerate the disease in animals [Review of Harmful Gastrointestinal Effects of Carrageenan in Animal Experiments] [ref] (requires Adobe PDF Reader). Its pro-inflammatory effects in humans are troubling too [Pro-inflammatory NF-κB and early growth response gene 1 regulate epithelial barrier disruption by food additive carrageenan in human intestinal epithelial cells] [ref].
This emulsifying and jelling agent has no nutritional value. The European Food Safety Authority found that cassia gum had the potential to cause worrisome irritating and sensitizing effects [Scientific Opinion on the safety and efficacy of cassia gum for dogs and cats based on a dossier submitted by Intercolloid (UK) Ltd] [ref] (requires Adobe PDF Reader).
Guar gum is economical because it has almost eight times the water-thickening potency of cornstarch - only a tiny quantity is needed for producing a stiff texture in almost anything. It is often used in the food industry but the biggest use today is in the petroleum fracking process where it is injected into the ground and in sewage plant water purification. It appears to have the potential to be irritating in its own right and to sensitize the immune system [Persistent specific bronchial reactivity to occupational agents in workers with normal nonspecific bronchial reactivity] [ref] [Prevalence of occupational asthma and immunologic sensitization to guar gum among employees at a carpet-manufacturing plant] [ref].
Maltodextrin is another thickening and binding agent. It is often used in commercial pet treats (particularly the soft or chewy ones). It too was found to disrupt the colon’s mucus barrier and allow bacteria to cling to the intestinal wall [Crohn’s Disease-Associated Adherent-Invasive Escherichia coli Adhesion Is Enhanced by Exposure to the Ubiquitous Dietary Polysaccharide Maltodextrin] [ref] (requires Adobe PDF Reader). [Deregulation of intestinal anti-microbial defense by the dietary additive, maltodextrin] [ref] (requires Adobe PDF Reader).
Products like these that alter optimal conditions in your pet’s intestines have the potential to effect processes far from the digestive tract - as a recent study in children revealed [Gut Microbes May Help Determine Our Immune Response to Vaccines] [ref] (requires Adobe PDF Reader) [Dietary clues to the pathogenesis of Crohn's disease] [ref].
Did You Know? A well formulated biologically specie appropriate raw food formula for dogs contains no chemical preservatives, artificial flavours, colouring chemicals or undesirable chemicals at all. Typical formulas will include Vitamin E (as designed & produced by nature), fresh apples and fresh bananas as natural preservatives. Some formulas also include raw Apple Cider Vinegar.
Additional Articles and Videos
Good reference articles & videos further reading available at:
- U.S. Department of Health and Human Services, National Toxicology Program, Report on Carcinogens, (Current Edition) (http://ntp.niehs.nih.gov/annualreport/2015/analysis/roc/index.html)
- "These Dog Food Preservatives Could Be Toxic to Your Pet", by DogFoodAdvisor (http://www.dogfoodadvisor.com/red-flag-ingredients/dog-food-preservatives/)