Science of Pet Food Labels
Read Before You Buy - What is Your Pet Food Package Telling You?
For the conscientious pet owner, shopping for pet food can be frustrating and bewildering. Which is best for your pet's health? Is the pretty picture on the package indicative of the food inside? Or does the higher price mean higher quality? There is only one way to know, and that is to read the list of ingredients - but you have to know how to read them.
What is in a Name?
How a food is named is an indication of the amount of good ingredients it has, but this can get very tricky. That's why the names that are given to pet foods is watched closely by the agencies that regulate pet foods.
The rules for naming go like this:
The ingredient list must be printed in order of most to least amount of the ingredients present, so when "chicken" is the first ingredient in a food, "ground yellow corn" the second, and "corn gluten meal" the third, you can be sure that by weight, there is more chicken than ground yellow corn, and more ground yellow corn than corn gluten meal.
If the food begins with the meat ingredient in the name, then the product must have at least 95 percent of that meat. Beef Dog Food, for example, would have to meet this rule.
If the product has the words dinner, entree, platter, or formula, the ingredient named needs to be at least 25 percent of the product. Using the previous example, now changed to Beef Dog Food Dinner, the food goes from 95 percent meat content to anywhere from 25 to 95 percent content. If there is a combination of meats, such as a Chicken and Fish Entree, the product must have a combined 25 percent of both meats, but more chicken than fish, since chicken is named first. The amount of the meat in these cases would be indicated by their place on the ingredients list.
The word with on the package has another rule - this one requiring an even smaller amount of the meat named on the label: 3 percent. For example, Dog food with Beef need only have 3 percent beef to meet the required amount.
The word flavor added to the name has the least amount of meat. For these products, only a detectable amount of meat needs to be present to use it in the name of the product. That beef dog food, when renamed Beef Flavored Dog Food, becomes a food that is very low in beef, but which tastes and smells like beef because of the addition of meat broths.
By-Products, Fillers, and Splitting
Generally speaking, a by-product is a part of the animal that is not normally intended for human consumption. This can include the lungs, spleen, kidneys, brain, livers, blood, bone, stomachs, and intestines of meat animals, and the necks, feet, undeveloped eggs, and intestines from poultry. By-products do not include hair, horns, teeth, or hoofs. In many cases, by-products are high in nutritional value and are not at issue.
Fillers, on the other hand, are not only be used to replace higher quality ingredients, they may also be biologically inappropriate for your pet and may lead to health and weight problems. For example, cats should not be eating foods with corn in the ingredients, and in fact should have as little filler as possible in their foods, since cats are meat- and not vegetable-eaters.
Conversely, many experts agree that fillers are a necessary ingredient in dog foods, since the total nutritional food value must include a combination of fats, proteins, carbohydrates, minerals, and vitamins. Fillers can be nutritious when done right, but done wrong, fillers can lead to obesity and high blood sugar. This goes back to reading the ingredients list. The trick, again, is knowing the good fillers from the bad fillers. Healthy amounts of corn and rice can be good for your dog; corn syrup, and MSG (monosodium glutamate) are never good. Look for foods that list the fillers low on the list so that you know your dog is not getting an unhealthy amount of fillers.
Splitting is a term used for when the same ingredient are listed in several guises within the first five ingredients so you will believe you are getting more (or less) of that ingredient than you really believe you are. For example, a cat food may have fish broth as the first ingredient, corn gluten meal as the second, fish as the third, and animal fat preserved with ground yellow corn as the fourth. It looks as if fish is a big part of the food, but this is a corn-based product.
Check out the Nutritional Analysis
All pet foods are required to meet minimum standards for protein, fiber, fat, and moisture. These minimums are based on an as fed basis and include the moisture used for processing. For dry foods, dry matter percentages can be calculated by taking 100 percent minus the amount of moisture in the food (10 percent on average) and dividing the percentage listed by the percentage of dry matter.
For example, a dry food with 10 percent moisture is: 100 - 10 percent moisture = 90 percent dry matter. Taking 20 percent protein and dividing it by 90 gives you 22 percent protein on a dry matter basis. You can also use this formula to calculate the amount of fiber and fat in the food.
Make Sure it is Complete and Balanced
The Association of American Feed Control Officials (AAFCO) requires all foods to meet standards for nutritional adequacy. This is necessary for a product to be labeled as complete and balanced. The label should also tell you which life stage the food is meant for, such as growth stages for young pets, maintenance, or senior stage.
Feeding Instructions and More
All pet foods should have a general guideline printed on the package for feeding your pet. This is based on body weight and age, generally. Additionally, the package will list the companies that manufacture the food and distribute it. Most companies will list an address or phone number so that you can contact them in case of problems, questions or complaints.