“Corn-free dog food is an important part of a healthy diet for your dog.”
Corn “can assault the sugar-controlling functions of both the liver and the pancreas, hence leading to medical conditions like dog obesity, pancreatitis, diabetes, and liver disease.”
■ There is no shortage of warnings on the Internet that corn is bad for your dog’s health. And the explanations given for the alarm can sound scientifically credible to people who are not scientists. But they’re not. Corn has been regularly included in commercial dog food for decades, and dogs are only getting healthier and living longer. Take a look at the buzz that passes for fact against the actual science.
Myth: Corn in dog food is just filler to add weight and volume and replace meat, which is much more expensive.
Fact: Corn is a rich source of linoleic acid, an essential fatty acid that dogs must get in their diets. It also contributes vitamins and minerals, along with some of the fiber dogs require. In addition, corn is a good source of the phytonutrients lutein and zeaxanthin, which are being investigated for potential health benefits.
Myth: Corn cannot be digested, or digested properly, by dogs.
Fact: It has been said that dogs are not able to digest the carbohydrates in corn (or in other foods, for that matter) because they lack an enzyme in their saliva called amylase that helps break them down. But dogs do secrete amylase. It comes from their pancreas rather than from saliva (in people, pancreatic amylase is much more important than salivary amylase), and it then passes into the upper portion of the small intestine where much of digestion takes place.
Some argue that because amylase does not enter the digestive process right in the mouth, the carbohydrates in corn (and other grains) cannot be broken down adequately. But that’s not true. A dog’s intestine digests corn just fine, and nutrients from corn then enter the bloodstream and travel to all the body’s tissues, where they fuel and maintain cells.
Granted, if the corn is wholly uncooked, it will not be highly digestible. But whole ground corn cooked via extrusion (the way most dry dog foods are made), has been shown to be 97 percent digestible by dogs. Dogs fed whole sweet corn kernals may pass small pieces of the outer hulls of the corn in their stool, but this doesn’t mean that the rest of the nutrients from inside were not absorbed.
Myth: Because dogs are carnivores, like their ancestors the wolves, they should simply not consume carbohydrates of any kind.
Fact: Dogs are not wolves and, more importantly, they are not carnivores. They thrive on a mixed diet of both animal foods and plant foods. Moreover, wolves don’t make for a good comparison to the lifestyles of today’s pet dogs. They live for only a few years in the wild — long enough to procreate and then die from illness or attack by other animals. In other words, what’s optimal for a wolf is not relevant to what’s optimal for our companion dogs, who generally live longer than a decade and sometimes closer to two decades. Finally, researchers have reported that dogs have genetic differences from wolves that are critical for starch digestion.
Myth: Because corn is rich in carbohydrates, it overwhelms the sugar-controlling functions of the pancreas, leading to dog obesity, diabetes, and other serous conditions.
Fact: Carbohydrates do not cause diabetes, either in dogs or people. They need to be monitored only in dogs (and people) who have already developed that condition. Carbohydrates don’t cause obesity, either. It’s caused by consuming too many calories and insufficient physical activity to burn them off.
Myth: A lot of dogs are allergic to corn.
Fact: Corn gets blamed for allergic reactions that include skin irritation, hair loss, tumors, blindness, deafness, and inflamed kidneys. But allergies to corn are rare.
Why would a corn allergy be uncommon? It’s because allergies to animal proteins — those present in meat, poultry, and dairy products — are much more apt to occur than allergies to a source of carbohydrates. Even animal foods rarely cause food allergies. Dogs who develop allergies tend to have them from allergens in the environment — pollen, dust, and mold, for example.
The takeaway: It’s fine for corn to be an ingredient in your dog’s diet. Corn even offers nutritional advantages in its mix of vitamins, minerals, and other nutrients.