choosing pet foods

Labels & Guaranteed Analysis

• Pet Food Labels

• What are good numbers for protein, fat, carbs, fiber, and ash?

• How to evaluate foods using the numbers

• True cost to feed

We are faced with multiple food choices, e.g. dry food, canned food, dehydrated foods, frozen foods. What is the best food to feed is dependent on who is providing the answers. Almost every food you find will be sold as a “complete and balanced” food labeled as meeting the Association of American Feed Control Officials (AAFCO) nutritional adequacy standard regardless of the price. The question is do we wish to feed a food that is adequate or choose optimal nutrition. So the question remains, how do we select the best foods? We begin with the information provided by the pet food companies listed on the product label or at their website. What is missing from this information is the actual quality and digestibility of the food along with the amount of ash, total dietary fiber, and carbs. For a food to be high quality it needs to be both highly digestible and contain usable essential amino acids that have actual nutritive value once digested. Since companies do not provide a true quality score for pet foods we are left with evaluating the ingredients, calories, nutrient analysis, and doing our own calculations to determine the protein, fat, and carb content, and to uncover things like high ash, and total dietary fiber. We can use the label information to determine the actual minimum grams of protein, fat, and carbs, and we can determine the calorie breakdown to determine protein, fat, and carb balance. Once you understand how to use this information you can uncover errors and potentially misleading information.

Start by locating these 4 items on the label or website: (warp & woof)

1. Guaranteed Analysis

2. Calorie Content

3. Ingredients

4. Nutritional Adequacy Statement

Guaranteed Analysis

Dog and cat foods in the USA are required to list a “Guaranteed Analysis” of the nutrient content of the food. The guaranteed analysis lists protein, fat, fiber, and moisture percentages as minimums or maximums and is not meant to provide exact percentages. The actual amounts can vary a little or a lot from the guaranteed analysis so I will show you how to determine this. Pet food manufactures in the USA are not required to list “ash” or “carbohydrates” in the food but some will provide this information if asked or have it listed on their website.

In Europe rather than use the “guaranteed analysis” which only provides minimums and maximums, they list a “Typical Analyses” which reports the “typical” averages for the food. These percentages are generally much closer to the actual food composition than what is reported with the guaranteed analysis. A typical analyses following European guidelines includes protein, fat, fiber, ash, and moisture if more than 14%.

We cannot compare foods based on the "Guaranteed Analysis" alone since these numbers do not represent the full nutrient profile of the food. Differing types of foods (dry, canned, dehydrated, raw, etc…) have different amounts of moisture (water) so they will have great differences in the percentage of protein and fat listed on the label. Just subtracting the moisture content and comparing foods on a dry matter basis is not sufficient. To determine the actual amounts of protein, fat, and carbs in a food we need to know the calories.

Calorie Content

Most commercial pet foods list the calorie content on the label. Calorie content is not a guarantee but rather an average. Calories on pet foods are generally listed as “kcal” which is the same as a “calorie” on human food labels. Calories will usually be listed as kcal/kg which the number of calories per kg which is 2.2lbs. (e.g. 3678 kcal/kg) Additionally calories will often be listed for calories per cup (419kcal/cup), or calories per oz. In Europe calories are often listed as calories/kcal per 100 grams. Using the calorie content and the guaranteed analysis we can discover and uncover a lot of information about a food by running a few calculations.

Ingredients

Quality of ingredients? Fresh, Highly Processed, Whole Foods, Synthetics

“As with human foods, federal law requires that pet food companies report all included ingredients in decreasing preponderance by weight on their product’s label. This means that ingredients that are listed first are present in the highest amount in a given product. However, and here is the catch, the weight of each ingredient includes the moisture (amount of water) present in the ingredient at the time of processing. This makes interpretation a bit tricky because some ingredients contain a lot of water (up to 70 %) while others contain very little water (12 % or less). The result is that an ingredient that is listed first on the list may appear to be the most important component of the food, when in effect it contributed a lot of water and much less in the way of essential nutrients. When evaluating dry dog foods, a general rule of thumb is that the first five ingredients that you see in the list provide 80 % or more of the food’s nutrients.” [5]

Quality can vary greatly and it is affected by the source, type of ingredients, formula, heat, processing, fiber, and ash content. When comparing foods, ingredients can look the same as listed but but quality can be poor, moderate, or high quality. If you are not familiar with ingredient splitting, “fairy dust”, amino acids, meats, meals, by-products, plant based protein, fiber, ash, digestibility, etc., start here: Dog Food 101

Nutritional Adequacy Statement

Dog and cat foods will have a “Nutritional Adequacy Statement” which will state whether the food is “Complete and Balanced” for their age and “life stage”.

“Complete and balanced” for:

• Adult Maintenance

• Growth/Reproduction (Puppies, gestation/lactation)

• “All Life Stages”

• All Life Stages, including for growth of large size dogs (70 lb or more as an adult) (See below) 

A food “Complete and Balanced” for “Adult Maintenance” is designed to meet the nutritional levels for adult dogs but not pregnant, nursing dogs, or puppies. A food that is “Complete and Balanced” for “All Life Stages” is designed to meet adequate nutritional levels established by the AAFCO for pregnant dogs, nursing dogs, growing puppies, and mature dogs. If the label states the food “is intended for intermittent or supplemental feeding only” it does not provide complete nutrition so it is not “Complete and Balanced”.

In Europe the term used is “complete” which means the food contains all the nutrients for a balanced diet. Instead of the term intended for “intermittent” or “supplemental” feeding they use the term “Complementary” to denote the food is not “complete” or “complete and balanced”.

Amount of Protein, Fat, Carbs, Fiber, and Ash?

First lets review the recommendations and ranges for protein, fat, carbs, fiber and ash. Then I will show you a simple way to evaluate a food the way professional food scientists and formulators do so you can see how a food compares to these ranges.

Protein

Pet food labels do not list the amount or grams of protein like human food nutrition labels. But using the guaranteed analysis and the calories content we can determine the minimum grams (g) of protein for every 1,000 calories/kcal the way nutritionist evaluate foods. (Pet Food Math Cheat Sheet)

We can group foods by low, moderate, or high protein content. Keep in mind that a poor quality high protein food is not necessarily better than a high quality low protein food. (See Dog Food 101)

Canines

For healthy dogs a high protein diet is not going to be a health problem. [7] Actually a high protein diet is recommended for both overweight and senior dogs.

• 75g > per 1,000 calories/kcal - Healthy senior dogs [9] Dr. Justin Shmalberg, board-certified Veterinary Nutritionist DVM, DACVN, DACVSMR]

• 70 - 90g > per 1,000 calories/kcal - Weight loss [8] Dr. Justin Shmalberg, board-certified Veterinary Nutritionist DVM, DACVN, DACVSMR]

• My goal is a minimum 75 grams per 1,000 calories/kcal and my target range is 80-110 grams per 1,000 calories.

Felines

“Cats fed a high-protein diet consumed a higher num­ber of calories than those on a lower-protein diet and better maintained their weight following weight loss.” High-protein diets are recommended during weight loss and a diet of 120 grams per 1,000 calories is recommended for cats to preserve lean body mass. [10] Finding a cat food with 120 grams of protein per 1,000 calories is a difficult task. One that meets and exceed 120 grams is the Lotus canned cat food line Just Juicy.

Fat

“dogs are naturally more efficient at using fat as a fuel for exercising muscles than carbohydrate (glycogen), even when exercising at relatively high intensities.” [5] “Dog can tolerate high levels of dietary fat if fat is gradually introduced and adequate intake of non-fat nutrients in maintained.” [4]

Carbohydrates

Dogs have “no minimum dietary requirement for simple carbohydrates or starches”. “The primary purpose for adding carbohydrates and starches to pet foods is to supply energy.” [11] “There are three key advantages to limiting dietary carbohydrate to 20% (DM) or less: 1) lower glycemic index, 2) metabolic shift from energy storage to energy usage and 3) increased satiety.” [11] (DM = dry matter) When energy needs are high (e.g. during growth, gestation and lactation) carbohydrates can supply energy (calories). “foods fed to growing animals and those with high-energy needs should contain at least 20% carbohydrates.” [11] During gestation female dogs can do fine on a carbohydrate-free diet but they will require a higher protein diet. [12] “The controversy about starch in dog foods revolves more around how much starch is in the food” [1] Animal nutritionist Dr. Richard Patton and many others advocate for a low carbohydrate diet similar to their wild ancestors diet of between 2-7% of calories coming from carbs. (See calorie breakdown)

Fiber

“The measure of fiber is typically reported on pet food labels as “crude fiber”. This analytical method does not capture all forms of fiber and largely reports the insoluble portion. A better value used for human foods is total dietary fiber, which includes both soluble and insoluble fibers.” [13] Crude Fiber underestimates total dietary fiber (up to 4-fold). In general, a dry dog food that contains between three and seven percent fiber (listed as “crude fiber” on the label) is considered normal and beneficial.” [1] “a small amount of fiber (<5%) that contains both rapidly and slowly fermentable fibers is recommended in foods for healthy pets” [4] “A dry food that reports a crude fiber content that is higher than 5 or 6% has added fiber.” [1]

Crude fiber* < 6%

*High levels of fiber can negatively affect a food’s digestibility. [12]

Ash

Ash is the inorganic material left after organic material has been burnt. Ash is what’s leftover after the food has been incinerated and the protein, fat, and carbohydrates of all been burned away. It is generally the mineral content of the food.”  e.g. bone meal, calcium, phosphorus, and trace minerals. [14] Ash can come from bones, animal meals, and mineral supplements. A food with high ash content is likely made with a large amount of bone e.g. “chicken frames,” Since frames would also contain a lot of connective tissue this lowers the protein quality. Protein sources containing higher quantities of muscle meat will contain less ash. “High-quality dry pet foods generally contain between 5% and 8% ash.” [12] “Ash content is generally “between 2% and 10% using higher values with dry, higher protein foods” [13] Higher moisture foods will generally have 1 1/2% - 2% ash. (e.g. canned, fresh, and frozen raw)

Ash (General range*)  

• Dry food 5-8%

• Freeze-dried/dehydrated 10%

• Canned food 1.5-2%

• Commercial raw 1.5-2% 

*High levels of ash can negatively affect a food’s digestibility. [12]

How To Determine What’s in the Food?

All food consists of protein, fat, fiber, moisture, and ash. Protein, fat, and digestible carbohydrates are the nutrients providing the calories (energy).  

Enter the information from the "Guaranteed Analysis" (or typical analysis / nutrient analysis) and the "Calorie Content" on the food label and the cheat sheet will do the math so you can compare any type of food.

We need to know both the calorie breakdown (%) where the calories come from with regards to protein, fat, and carbs, and the grams of each for each 1,000 calories fed. I show you how to simply determine this.

• My ideal food would be the following percentages.

• 45-50% of calories from quality protein (animal based)

• 35-44% of calories from fat

• 6-20% of calories from carbohydrates (Closer to 6% the better)

Using the nutritional information provided we can quickly determine how close those numbers are to what’s actually in the food using the Pet Food Math Cheat Sheet. The Pet Food Math Cheat Sheet can also uncover errors and potentially misleading information. (e.g. high “ash” content, high fiber content, high fat content, and carbs, etc.)

.

We want to two things, the actual minimum amounts of protein, fat, and carbs with regards to the total number of grams per 1,000 calories/kcal. This will show us how the food fits into the nutritional profiles. Then we need to determine the calorie breakdown for protein, fat, and carbs.

“The best way to analyze any food is the way professional food scientists and formulators do—by looking at where the calories come from. In other words, they analyze foods on a caloric basis” [3] To compare foods we need to know what percentage of calories come from protein, fat, and carbohydrates, and how many grams (g) of protein per 1,000 calories the food provides. To determine this we need "Guaranteed Analysis" and the "Calorie Content" to run the calculations.

Percentage of calories from protein, fat, and carbs in various foods.

Note that the percentage of calories is not the same as the "guaranteed analysis" %.

• Amount of protein, fat, & carbs?

  • Low, Medium, or High

• Calorie Breakdown

  • protein, fat, and carbs

Protein

Protein content is all over the board. (Not to mention the quality of the protein) There are two numbers (actually three) with regards to amount of protein. The first is the grams of protein per 1,000 calories (kcal). The second is the percentage of calories the protein provides. The third number is the protein digestibility number which companies almost never tell us.

After doing my own homework I came to the conclusion that words and numbers are of equal value when choosing a food.

"There are a number of commercial foods available today that are advertised as being more economical to feed while still providing superior nutrition. However, it is important for pet owners to know that to produce a low-cost product, ingredients that are of lower quality, and thus lower cost, must be used. Therefore a cheaper product is probably going to be a lower-quality food, even though the guaranteed analysis panel may not reflect this. In addition, when considering the price of a pet food, the actual cost of feeding the animal must be calculated, not just the cost per unit weight of the food. Most low-quality, cheap ingredients have significantly lower digestibilities than the ingredients used in premium foods. A greater quantity of a food with low digestibility must be fed to an animal to provide the same amount of nutrition as found in a food with higher digestibility and nutrient availability.” [5]

Below are two foods and each meets the nutritional adequacy standard for adult food. The cost, ingredients, and guaranteed protein levels were current at the time of this comparison.

Food A

(39 ingredients) Whole grain corn, meat and bone meal, corn gluten meal, beef fat naturally preserved with mixed-tocopherols, soybean meal, poultry by-product meal, chicken, egg and chicken flavor, whole grain wheat, animal digest, salt, calcium carbonate, potassium chloride, mono and dicalcium phosphate, L-Lysine monohydrochloride, choline chloride, MINERALS [zinc sulfate, ferrous sulfate, manganese sulfate, copper sulfate, calcium iodate, sodium selenite], VITAMINS [Vitamin E supplement, niacin (Vitamin B-3), Vitamin A supplement, calcium pantothenate (Vitamin B-5), pyridoxine hydrochloride (Vitamin B-6), Vitamin B-12 supplement, thiamine mononitrate (Vitamin B-1), Vitamin D-3 supplement, riboflavin supplement (Vitamin B-2), menadione sodium bisulfite complex (Vitamin K), folic acid (Vitamin B-9), biotin (Vitamin B-7)], Yellow 6, Yellow 5, Red 40, Blue 2, garlic oil.

• Minimum protein guarantee is 21% and 59 grams of protein per 1,000 calories.

• I estimate 44% of the calories are from carbs.

Food B

(22 ingredients) Beef, Chicken, Beef Liver, Chicken Liver, Chickpeas, Sweet Potatoes, Ground Flaxseed, Coconut Oil, Salt, Kelp, Broccoli, Spinach, Beets, Carrots, Tomatoes, Cranberries, Oranges, Apples, Cherries, Blueberries, Strawberries, Mixed Tocopherols (a preservative).

There is a huge difference in cost and I believe in quality between these two foods. Food B actually costs more then 25-times the cost of food A. More on that later. Food A looks to derive a lot of protein from plant and not animal sources. Food A does not list what animal sources are in the food but instead lists mystery meats which is considered low quality. In addition to having a lot of carbs, food A lists a synthetic amino acid, and artificial colors. For more information on pet food ingredients go to Dog Food 101.

Food B reports over 80% of the protein is from named animal sources. Food B is low carb and contains no synthetic ingredients, or artificial colors, and is minimally processed. Food B gets all it nutrients from nature and not the science lab. (No synthetic amino acids, vitamins, minerals, etc.) Although food B lists 35% protein it actually guarantees less protein then Food A (21%) when you compare grams of protein per 1,000 calories. (I’ll show you how to uncover this information like a nutritionist quickly and simply) In reality I believe food B actually provides a much greater amount of usable (quality) protein a dog will be able to digest and use compared to food A. I suspect food A has a low digestibility and dogs eating food A will leave a demonstratively large pile on the lawn in comparison to food B.  

[1] Case, Linda. Dog Food Logic - Making Smart Decisions For Your Dog In An Age Of Too Many Choices. Dogwise Publishing.

[2] https://todaysveterinarypractice.com/nutrition-notes-treatment-of-obesity/

[3] https://www.ncbi.nlm.nih.gov/pubmed/11991408

[3] Brown, Steve. Unlocking the Canine Ancestral Diet: Healthier Dog Food the ABC Way. Dogwise Publishing

[4] https://www.nomnomnow.com/learn/dog-nutrition-basics/how-to-read-dog-nutrition-labels

[5] Case, Linda P.; Daristotle, Leighann; Hayek, Michael G.; Raasch, Melody Foess. Canine and Feline Nutrition: A Resource for Companion Animal Professionals. Elsevier Health.

[6] https://www.petfoodindustry.com/blogs/10-debunking-pet-food-myths-and-misconceptions/post/8087-update-can-petco-be-petcoached-to-be-petsmarter

[7] https://www.petfoodindustry.com/blogs/10-debunking-pet-food-myths-and-misconceptions/post/6572-pet-food-nutrition-its-not-just-about-high-protein

[8] https://www.nomnomnow.com/obese-dog-weight-loss

[9] https://justinshmalberg.com/blog/2018/4/17/senior-dog-nutritional-requirements

[10] https://todaysveterinarypractice.com/nutrition-notes-treatment-of-obesity/

[11] Small Animal Clinical Nutrition, 5th Edition Hardcover – Michael S. Hand (Editor)

[12] Case, Linda P.; Daristotle, Leighann; Hayek, Michael G.; Raasch, Melody Foess. Canine and Feline Nutrition: A Resource for Companion Animal Professionals. Elsevier Health.

[13] Applied Veterinary Clinical Nutrition. Wiley.

[14] Brown, Steve. Unlocking the Canine Ancestral Diet: Healthier Dog Food the ABC Way . Dogwise Publishing

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