Dogs used to eat whatever scraps people gave them. The first commercial dog food was developed a little over 140 years ago by James Spratt, in the form of a biscuit. Spratt's dog biscuits were popular, and other companies also began to manufacture pet foods. At first, these foods were available only in feed stores, but by the 1930s they could be found in grocery stores as well. Canned foods were most popular, but the invention of the extrusion process to create dried food pellets propelled dry foods to the top spot in dog owners' hearts. Dry food was less expensive and easier to feed. Today, dog owners can choose from a wide variety of commercial canned, dry, frozen, and dehydrated dog foods.

What Type of Food Is Best?

Dogs are individuals, and different dogs do better on different types of foods. Whether you choose a canned, dry, or other type of dog food depends not only on your dog's needs, but also on your budget, what's most convenient for you, and how you feel about certain types of ingredients. Consider all these factors when you're choosing a food. Each type has advantages and disadvantages.

Dogs like the taste of canned food, and it may make you feel as if you're offering a substantial meal. It has a long shelf life until it's opened. On the down side, canned food is expensive, and it must be refrigerated after it's opened. Dry food is easy to scoop out, measure, and serve. It's less expensive than canned food and doesn't need to be refrigerated, even after it's opened. And dogs often like the crunchy texture. Dry food doesn't have much of a down side, although most dogs, if given a choice, will prefer canned food. There's nothing wrong with adding a little flavor to a dry meal by mixing it with some canned food. That can help you stretch your dog-food budget and satisfy your dog's taste buds.

More recently manufacturers have begun preparing frozen and dehydrated foods for dogs. Frozen diets are prepared fresh, made into rolls, cubes, or loaves, and flash frozen so they don't need artificial preservatives. The lack of heat processing preserves heat-sensitive vitamins and amino acids that would otherwise be damaged. The disadvantage is that you have to remember to thaw it before use (although many dogs are satisfied to just gulp it down frozen).

Dehydrated foods (which have all the water removed from them) are prepared at a temperature low enough to preserve the value of the vitamins, minerals, and other nutrients yet high enough to kill any bacteria. Just mix them with warm water, and they're ready to feed. Dehydrated foods have the long shelf life and easy storage of canned and dry foods. Rehydrated food must be refrigerated if your dog doesn't eat all of it at one sitting, but it's easy to prepare only the amount you need so he doesn't have any leftovers.

Popular, Premium, Natural, and Organic Foods

What do these terms mean? That's a good question. Lots of labels are applied to dog foods, but they don't always have a clear-cut meaning or government-approved definition. Dog food is often categorized as popular, premium, or generic. Popular foods are the national or regional brands that you find in grocery stores. They're made by well-known manufacturers that spend a lot of money researching canine nutritional needs and testing their foods by feeding them to dogs. One potential disadvantage of these foods is that their formulas can vary from batch to batch, depending on the cost and availability of their ingredients. Some dogs suffer tummy upset when their diets change, so this is a factor to consider in choosing a dog food. In general, popular foods aren't as digestible as premium foods, but they're of better quality than generic foods.

Premium foods are found primarily in pet supply stores. They contain high-quality ingredients that provide good to excellent digestibility and are prepared according to fixed formulas, meaning that the ingredients don't change. Some premium foods may contain organic or human-grade ingredients. Premium foods are expensive, but because of their higher digestibility you can feed less of a premium food than of a popular or generic food, which brings down the cost per serving.

Premium foods are often labeled as organic or natural. That definitely sounds good, but it doesn't have any real meaning. The term “natural” doesn't have an official definition. Instead, it is usually used to mean that a food doesn't have any artificial flavors, colors, or preservatives. The term “organic” simply refers to the way plants were grown or animals were raised (usually without the use of pesticides or fertilizers or only certain types of pesticides or fertilizers).

Currently, the United States Department of Agriculture (USDA) does not have any rules governing the labeling of organic foods for people or pets, although this will probably change in the future. Just because a dog food is labeled premium, superpremium, natural, organic, or gourmet does not mean that it actually has to meet any higher or different standards than other foods. Call the manufacturer — companies are required to provide contact information on their labels — and ask for specifics on what their claim actually means.

Generic Foods

Low-cost generic foods are attractively priced, but that's because they use poor-quality ingredients to keep costs down. The nutritional quality of generic foods is rarely confirmed through AAFCO feeding tests, and some may not even carry a nutritional adequacy statement. This is one of those instances in which you get what you pay for. In fact, because of the low level of digestibility, it's necessary to feed a lot more of a generic food than a popular or premium food to ensure that a dog receives adequate nutrition, so the savings are illusory.

Canine Health Foods

Nutrition plays an important role in overall health, and diet can be effective in managing certain illnesses. Certain diets, known as veterinary medical foods, are formulated to meet these needs and are available only from your veterinarian. Because they have specialized nutrient content, they're not appropriate as regular diets. Because a veterinarian supervises the use of veterinary medical foods, these diets are exempt from the AAFCO requirement that food labels include feeding directions. If this type of diet is prescribed for your dog, he may need to eat it temporarily or, in some instances, for the rest of his life. Conditions that may be helped by diet include cancer, diabetes, food allergies, or kidney or liver disease.

Don't Believe Everything You Read

You will often see foods that claim to promote “healthy skin” or a “shiny coat.” Be aware that this type of claim doesn't have any real meaning; any good-quality food will give your dog healthy skin and a shiny coat.

The Food and Drug Administration's (FDA's) Center for Veterinary Medicine (CVM) monitors the health claims made for foods. Manufacturers may not state on a pet food label that a particular food can treat, prevent, or reduce the risk of a certain disease. Health-related information on the label must be supported by research and approved by the CVM. That's why you're unlikely to see claims that a food will “improve” skin and coat or “prevent” dry, flaky, or itchy skin. Certain substances such as omega-3 fatty acids may indeed help control inflammatory skin disease, but they aren't currently recognized as essential nutrients for dogs, so dog food manufacturers that include these fatty acids in their foods can't make unqualified claims on the label regarding the benefits of supplementation.

Acceptable claims include those for dental diets, such as “helps control plaque” or “helps control tartar.” On the other hand, the label on a dental food may not claim to prevent or treat periodontal disease. Diets prescribed by your veterinarian to help treat a particular disease may not be labeled with drug claims, but the CVM does permit manufacturers to provide literature to veterinarians that will help guide them in using the product.