Dog Food: Separating Fact from Fiction
One of the single most important things that pet owners can do to help ensure the long term health of their pets is to feed them high quality/well balanced food. Like with humans, proper nutrition has a direct effect on both the quantity and quality of a pet’s life. You are what you eat– this statement holds true for animals and people alike as the link between nutrition and health has been long established. Animals need the same combinations of nutrients (protein, carbohydrates, fats, vitamins & minerals) as humans. Additionally, dogs (and cats) require different combinations of nutrition depending on their stage of life. For example puppies require a different type of diet than senior dogs.
There are so many types and brands of dog food that its dizzying and difficulty to know where to begin. However, the first step in choosing the right food for your dog is to have a basic understanding of your dog’s nutritional needs.
The Basics of Canine Nutrition
No matter what type of food you choose there are six major classes of nutrients that must be present in order to have a healthy and balanced diet: protein, fat, carbohydrates, vitamins, minerals and water.
PROTEINS: Proteins are complex molecules made up of 23 amino acids that support muscle growth and maintenance. Dogs produce just over half of these amino acids internally, the other half, termed “essential amino acids,” need to be provided by the diet. The 10 essential amino acids are arginine, histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan and valine.
FATS: Fats are the main energy source for dogs. They also supply the fatty acids that are essential to maintaining normal, healthy cells. Fats aid absorption of the fat-soluble vitamins A, E, D and K. Plus they make food taste great! Three very important fatty acids are Linoleic Acid, Omega-6 and Omega-3.
CARBOHYDRATES: Carbohydrates are sugars and starches that are rapidly converted to energy (glucose) by the body. Carbohydrates in the form of whole grains can furnish iron, minerals and fiber as well as other beneficial nutrients. Carbohydrates can be found in vegetables and fruit, which also supply minerals, fiber, antioxidants, phytochemicals and some protein.
VITAMINS: Vitamins are important in the conversion of calories to energy and helping the cells to use other nutrients efficiently. They are supplied in two basic forms: water-soluble vitamins that must be supplied daily because they are continually broken down and excreted, and fat-soluble vitamins that are able to be stored by the body.
MINERALS: Minerals are essential for producing and using energy, healthy teeth & bones, nervous & digestive system health and cellular functions throughout the body. They are supplied in two basic forms: major minerals that are required in gram amounts each day and trace minerals that are required in milligrams or microgram amounts per day.
WATER: Even if a dog loses all of his body fat and half his protein, he can still survive. But water is so important that he could die if he loses only 10% of the water in his body. Water makes up more than half of an adult dog’s body weight. Not only does H2O maintain hydration, it also cools the body, lubricates joints and internal organs, transports nutrients and removes waste.
As you may have guessed, the pet food industry is big business, reaching sales of over $27 billion dollars in the U.S. There are more brands of dog food than ever before, especially now that pet owners are demanding healthier ingredients. Pet owners can now choose traditional commercial food, fresh, frozen, made-to-order, prescription, dry, wet, grain-free, organic….and the list goes on and on.
But when choosing your dog’s diet, it is also important to understand the difference between higher quality diets and low quality. Higher quality diets include meat and/or meat meal, unrefined, minimally processed foods and healthy fats and proteins. High-quality named animal proteins should be the first ingredient, and, ideally appear more than once as top items on the ingredient list.
Higher quality diets also have whole fruit, vegetables and grains which contain the entire grain kernel. For example, rice rather than rice flour or bran. Refined grain products, gluten and mill runs should be avoided. The higher the quality of food the better it is for digestion. The more digestible the food, the more nutrients that are absorbed.
Low quality foods on the other hand contain byproducts, fillers, chemical preservatives, and artificial colors and flavors. Also avoid added sweeteners (which are usually listed as grain fragments); artificial preservatives such as BHA, BHT, ethoxyquin, and propylene glycol.
Like with all products, pet foods are the subject of slick marketing campaigns, making it confusing for pet owners to choose what is actually best for their pet. Pet diet trends and fads cycle around just like human diets. Below, we have listed a few of the current most popular diet trends to help you in make the most informed decisions, but speaking with your vet about all things concerning your pet is the best way to go.
GRAIN-FREE DIET
As a marketing techniques, nothing has been quite as successful as grain-free diets. “Grain-free is marketing. It’s only marketing,” said Cailin Heinze, a small-animal nutritionist at Tufts University’s Cummings School of Veterinary Medicine. “A lot of foods market themselves by what they’re not including,” and the implication is that the excluded ingredient must be bad.
Marketers try and link these grain-free diets to the meat based diets of dog’s ancestral kin such a wolves. They imply that these “wild animals” don’t eat grains so it must be better. Also they lead pet owners to believe that grain is a major cause of allergies in dogs.
However, There is no reliable evidence that suggests that it is harmful to feed grains as a group to dogs or cats. Whole grains, rather than being “fillers”, can contribute valuable nutrients including vitamins, minerals, essential fatty acids, and fiber to diets. The vast majority of dogs (and cats!) are very efficient (>90%) at digesting and utilizing nutrients from grains in amounts typically found in pet foods.
Also, food allergies in pets are uncommon, and allergies to grains are even rarer. The small number of pets that do have allergies are most likely to be allergic to animal proteins such as chicken, beef, and dairy.
Grain-free diets can vary widely in terms of their nutritional profiles including protein, fat, calories, and other nutrients. Some grain-free diets are lower in carbohydrates, which means that they can be quite high in both fat and calories. Other grain-free diets merely substitute similar amounts of highly refined starches such as those from potatoes or tapioca (cassava) in place of grains. These ingredients may provide fewer nutrients and less fiber than whole grains, while costing more.
RAW
Raw diets contain various meats (muscle, organ), some have fruits and veggies, and some have whole or ground bone. These diets can be homemade or bought commercially.
There are some anecdotal reports of benefits to a raw diets, but there is no scientific evidence pointing to any health benefit from raw diets. Some studies have shown a small increase in digestibility from raw diets compared to commercial dry diets. However, this may be the result of the ingredients, rather than the fact the diet was raw (the studies did not compare the raw diet to an identical diet that was cooked).
However, there are certain risks associated with raw diets. The first is that of nutritional imbalances, especially those that are homemade. Studies have found that 60% of homemade raw diets had major nutritional imbalances. Commercial raw diets has also been found not to met nutritional requirements despite with they claim.
Secondly, in addition to the many health problems that can develop as the result of deficient or excessive intake of nutrients (e.g., calcium: phosphorus imbalances), other risks of raw meat diets include gastroenteritis (inflammation of the gastrointestinal tract, usually resulting in vomiting and diarrhea) which could be due to bacteria in the diet or high dietary fat levels. For raw meat diets containing bones, gastrointestinal injury or fractured teeth can occur.
Also, raw diets have a high risk of contamination. Recent scientific studies have shown that a large percentage of raw meat diets (whether commercial or homemade) are contaminated with bacteria. Some of these bacteria are unlikely to have negative effects on health, but others can have serious consequences. For example, studies have found that up to 48% of commercial raw meat diets are contaminated with Salmonella. These diets can also pose a risk to the human family. Animals eating raw meat diets can shed these bacteria in their feces which can cause people to get infected. Even simple things like your pet licking your face could turn into a major health problem if your pet eats a raw diet.
EXOTIC DIETS
Until recently, the meat found in most, if not all, dog food was generally chicken, turkey, pork, or beef. But now dog food brands have ingredient lists that read like a zoo roster: duck, alligator, rabbit, venison, bison, ostrich and even kangaroo. They are marketed a being somehow more natural (as if chicken or beef are not) and that that are less likely to cause allergies. Oh, and most importantly, that come with a pretty sizable price tag.
Surprise! There is no benefit of including exotic proteins in pet food. They are not healthier than more traditional meats and consistent, high-quality sources of these proteins can be hard for companies to find–which can affect the quality and availability of the diet. As these animals are not raised on a large scale in the US for human consumption, many of them are imported from other countries in smaller batches, which causes their source, and availability to vary. Also the nutrient levels in these meats may be more variable with less available information than what is typically found in commodity meats such as chicken, turkey, beef, or pork.
Again, food allergies in pets are rare. But for pets that do have them, these allergies are developed to ingredients that the pet is regularly exposed to–things in their everyday diet rather than to specific foods like in people. “Feeding exotic proteins won’t prevent food allergies, they are no more or less allergenic than more common foods, they are just (until now) rarely found in pet food, so allergies to them are uncommon.” according to Veterinary Nutritionist Dr. Lisa M. Freeman, DVM, PhD, DACVN.
Therefore, ignore the shiny marketing materials and save yourself quite a bit of money. If you suspect your dog may have a food allergy, consult your veterinarian to discuss the appropriate diet and plan of action.
VEGAN DIET
There is an ongoing debate on whether or not dogs can thrive on a vegan diet. Those in the anti-vegan camp assert that a dog’s biology is not compatible with a vegan diet, while the pro-vegan camp claims that dogs can live a health life without any animal ingredients. While vegan diets (or home-prepared diets in general) can cause numerous health issues if not designed by an expert in canine nutrition, many of the arguments used against vegan diets are only partly true.
One argument is that the dog’s pancreas does not produce the right amount of enzymes to deal with the starch, cellulose, and carbs in plants. The pancreas’ job, among other things, is to produce the digestive enzymes that dogs need to digest their food. Most dogs’ pancreases work very well at this task and dogs do a very good job breaking down starch from plants. There is no evidence that feeding a higher carbohydrate diet damages the pancreas in any way.
Another argument is that dogs are not omnivores but true carnivores since they are decedent from wolves. As it turns out, dogs are classified in the Order Carnivora, but other species included in that group include omnivores such as bears, raccoons, and skunks as well as the giant panda, which is a strict herbivore. From a biological perspective, dogs lack most of the metabolic adaptions to a strict diet of animal flesh that are seen in true carnivores such as cats or ferrets. Compared to true carnivores, dogs produce more of the enzymes needed for starch digestion, have much lower protein and amino acid requirements, and can easily utilize vitamin A and D from plant sources, just as people do. We also have evidence that they evolved from wolves by eating more plant material. All of these factors make them more accurately classified as omnivores rather than carnivores.
In the end, the majority of dogs can fair very well on a CAREFULLY DESIGNED vegan diet that meets all of their nutritional needs. Dog owners who want to feed their pet a vegetarian and especially a vegan diet should consult with a veterinary nutritionist to create a diet that minimizes health risks.
HOMEMADE DIETS
The allure of making homemade food for your dog is almost irresistible. Food is one way humans show love–what better way to bond than over a yummy home-cooked meal. And what can be more emotionally gratifying than the idea of preparing all of your dog’s meals from scratch with your own two hands?
Despite popular beliefs, there is no science to support that home-prepared meals are in anyway healthier than commercial diets. As a matter of fact, it’s just the opposite. Home cooking can cause serious and/or long term damage to your pet’s health.
Making nutritionally balanced meals at home is surprisingly difficult and time-consuming. Commercial foods are legally required to meet certain nutritional criteria. And indeed, there are countless recipes on the internet, in books, and in magazines, (some more reputable than others), but studies have shown that the vast majority of recipes are deficient in one or more essential nutrients. What’s worse is that these deficiencies may not be evident for weeks, months, or years in a adult pet until a serious health issue arises that may not be easily reversed. Even with vitamin and mineral supplements made for pets, it is still not sufficient enough to make home-cooked meals complete and balanced.
Homemade meals can be a healthy diet option but it can not be approached casually. What’s more, home-cooked meals should never be given to puppies or nursing dogs. The best way to ensure that you are meeting all of your pet’s nutritional needs is to seek our recipes from a certified veterinary nutritionist with experience in formulating pet diets. This is even more important if you have a dog with existing health issues. It is also critical that you follow the recipe exactly because even the smallest substitution or omission and alter the nutritional integrity of the meal.
The World Small Animal Veterinary Association (WSAVA) has put together a global nutritional toolkit for both pet owners and veterinary professionals. You can download it here.
We encourage all pet owners seek nutritional guidance about their specific pet from either their veterinarian or a board-certified veterinary nutritionist [ACVN.org]. A veterinary nutritionist can help you determine what feeding options are best for keeping your pet healthy, prevent disease, and/or manage an existing illness.
References:
Canine Nutrition Basics: https://thebark.com/content/canine-nutrition-basics
A Pet Nutrition Primer: https://www.tasteofthewildpetfood.com/health/7-things-to-know-about-pet-nutrition/
Grain-Free Diets, Big on Marketing, Small on Truth: Veterinary Nutrition, Tufts University: https://vetnutrition.tufts.edu/2016/06/grain-free-diets-big-on-marketing-small-on-truth/
Raw Diets: A Health Choice or Raw Deal?: Veterinary Nutrition, Tufts University: https://vetnutrition.tufts.edu/2016/01/raw-diets-a-healthy-choice-or-a-raw-deal/
Alligator, Wild Boar, Ostrich – Oh My!: Veterinary Nutrition, Tufts University: https://vetnutrition.tufts.edu/2017/05/exotic_meats/
Vegan Dogs – A Healthy Lifestyle or Going Against Nature?: https://vetnutrition.tufts.edu/2016/07/vegan-dogs-a-healthy-lifestyle-or-going-against-nature/
Shoud You make Your Own Pet Food At Home?: https://vetnutrition.tufts.edu/2016/07/should-you-make-your-own-pet-food-at-home/
