Updated - Feb 28th, 2022
When we think about corn, we conjure up visions of corn on the cob, sweet corn slathered in butter and seasonings, and of course, popcorn – one of the most popular snacks at the movie theatre.
Corn, in various forms, has made its way into almost everything we eat. It’s an ingredient in sweeteners, sodas, processed meats, sauces and condiments, and yes, even in dog foods. But does that mean it’s a healthy snack or good for your pup? Let’s find out!
Corn is both a grain and a vegetable!
Whether corn is a vegetable or a grain depends on when it’s harvested and how it’s used. This also determines its nutritional value.
- Corn as a grain or cereal: Fully matured and dry, we consider corn grain or cereal, just like wheat, barley, or rice.
The edible portion of cereals is the seed head that’s typically ground into flour and cornmeal, or processed for products like corn syrup. Corn has the fattest seed head of the cereals with the highest sugar content. However, corn is not a dominant source of nutrients compared to the other grains considered cereals.
Products like popcorn, cornmeal, corn oil, cornstarch, corn syrup, and cornflour come from the cereal or grain version of corn.
- Corn as a vegetable: Fresh corn, the vegetable version, gets harvested when the corn is still soft and has high water content. We serve up the vegetable as corn on the cob, sweet corn, and mixed with other vegetables. It’s a starchy vegetable that offers some important nutrients.
Let’s look at some of those now.
Nutritional benefits of corn
Corn is a starchy source of energy that is high in fiber, carbohydrates, linoleic acid, and omega-6 fatty acids. It’s also high in antioxidants and an excellent source of potassium. Corn also contains some phytochemicals like carotenoids – believed to reduce the risk of chronic diseases. Let’s look closer:
- Fiber is vital for moving food through the digestive system and improving stool quality.
- Potassium is an essential mineral for good kidney function. It also supports efficient heart function, muscle function, and a healthy digestive system.
- Linoleic acid and Omega-6 fatty acids keep your dog’s skin and coat healthy.
- Carbohydrates are starches that produce energy by converting to glucose (or natural sugars) your dog’s body can use. Those sugars can be a problem for dogs with dental disease, obesity, or diabetes.
This sounds okay, right? Well, corn may have health benefits as human food, but it’s not as nutritious as you’d think for your dog.
Whole fresh corn kernels have insoluble fiber. The hull of the kernel is hard for your dog to digest, so it doesn’t digest completely as it moves through the digestive system. That’s why you see corn in your dog’s poop after a treat of corn from the table.
It still moves the food through the digestive tract, pulling food along with it, but the nutrients from the kernel of corn aren’t being absorbed if it comes out the same basic way it went in.
So in reality, the only thing your dog benefits from whole corn is the carbohydrates and the fiber.
That being said, corn is used in a lot of inexpensive dog foods and has gotten a bad rap in recent years. Let’s look at why corn can be beneficial in dog food.
Are dog foods containing corn bad for my dog?
Dog food formulators and manufacturers design it for a balance of essential nutrients your dog needs to be healthy and happy. Corn is typically used as a grain, meaning it’s processed into cornmeal, corn gluten meal, etc. Processing corn makes it more digestible for your dog. When processed for use in dog food, it acts as a binder, forming a gelatinous substance that allows a balance of all the meat, fats, vitamins, minerals, and carbs to stick together when they go through the extrusion process of making kibble.
Cost of corn is another benefit of using it in dog food manufacturing. Corn is inexpensive as a carbohydrate or even a protein (plant rather than meat) to make some dog foods more affordable. Sometimes it’s used excessively as a replacement for more expensive ingredients like meat proteins.
This is where corn has gotten a bad rap. Many pet parents believe that any corn in dog food is bad, but it really isn’t. There is a benefit to adding it, especially in prescription diets that need a highly digestible carb to bind with the beneficial ingredients used to support the recovery of a health issue. The corn used in these diets has been ground or processed, making it easily digestible for your pup and less likely to upset your dog’s stomach.
The benefit of corn in dog food is about what’s in the bag
The Guaranteed Analysis is your key to what’s in the bag. It lists all ingredients by order of their volume or representation in the formula. The first ingredient takes up the most weight (or represents the largest volume of ingredients) in the dog food formula, and so on, down the line. This is where the presence of corn makes a difference.
When you look at the Guaranteed Analysis, or ingredient panel, everything listed before the fat makes up most of the food. Usually, it will be the protein source (chicken, beef, etc.), the carb source (corn, potatoes, rice, barley, etc.), any meat meals (this is just the meat without the water), and the fats (fish oils, chicken oil, corn oil, or flaxseed oil, etc.). If corn is listed before the protein source, you know there will be more corn in the food than meat. That wouldn’t be a good use of corn or the healthiest diet for your dog.
If the ingredient panel listed whole corn, it’s actually fresh corn they ground prior to cooking the food for higher digestibility.
If it’s listed after the fat, that means the manufacturers used the corn as a filler – meaning there’s no nutritional value – or as a binder for the ingredients in the food. Additionally, due to all the controversy surrounding the use of corn, wheat, and soy, most commercial dog food manufacturers moved away from using them.
Is corn low on the glycemic index?
The Glycemic Index is a tool used to measure the speed foods raise blood sugar. The higher the score, the more likely that food will raise blood sugar to an unhealthy level.
Many believe corn is low on the Glycemic Index, but remember we’re talking about dogs who are smaller than us pet parents and possess different digestive systems. So let’s look at typical ingredients in dog food and see where corn ranks.
- Corn Meal (69)
- Brown Rice (55)
- Corn (53)
- Barley (25)
- Chicken (0)
- Beef (0)
As you can see, it’s not that low, and when processed, it ranks very high.
So corn is present in some dog foods for valid reasons and provides some nutritional benefits; it just depends on where corn’s listed on the Guaranteed Analysis that determines if that diet is truly healthy for your pup. If your dog has diabetes, or is overweight, the Glycemic Index ranking shows corn may not be the best choice for your dog’s health.
Are some dogs allergic to corn?
Dogs will show intolerances to some dog foods. But, more often than not, according to some studies done at Tufts University, the allergens affecting your dog are usually the proteins, and not the carbohydrate or grain source. And only 10% of dogs show a true allergy; most symptoms associated with skin problems are really food intolerances.
However, common allergen lists do include corn, but it’s listed below the animal proteins, dairy, and eggs.
If you think your dog may be allergic or have an intolerance to corn, your veterinarian can narrow down the symptoms to the allergen source to give some relief to your fur baby.
Signs of food intolerance are:
- Excessive Itchiness especially around the paws, ears, face, and belly areas.
- Inflamed skin in the same areas
- Red eyes that may have some discharge
- Hair loss, including patches of hair pulled out (hot spots)
Signs of food allergy are:
- Itching of the paws, ears, face, and belly
- Swelling of the face
- Chronic ear infections
- Weight loss
If you change your dog’s diet and see any of the above symptoms, talk to your vet. Note that sometimes it takes up to 12 weeks of eating a new food before any intolerances show.
Puppies have different nutritional needs than adult dogs, so offering new food may not be in their best interest. Their immune systems are still developing. As a result, they are more susceptible to gastrointestinal symptoms or upset tummies. Always talk to your vet before offering a new food to a puppy.
Corn as an occasional treat
With everything about corn laid out on the table, the research is clear: it’s not toxic, and letting your dog eat a small amount of corn causes no harm. In fact, there may be a few health benefits to offering it as a tasty occasional treat to your dog.
When considering treats, keep in mind that treats should only be 10% of your dog’s daily calorie intake. So their diet will comprise 90% of nutritionally balanced dog food, and 10% treats.
Let’s look at the best ways to offer corn to your dog.
No corn cobs
Corn cobs are the biggest danger when considering feeding corn to your dog. Many dog parents will toss a leftover corn cob to their pooch to snack on the leftover corn pieces. This is not a good idea!
Dogs will enjoy the tasty pieces of corn left on the cob, but the cob is NOT digestible. If your dog takes a chomp of the cob, they risk choking on it, or even worse, an intestinal blockage. This is especially true for large dogs known to take huge bites off their food and gulp them down. But it’s also hazardous to small dogs because their mouths and digestive tracts are so narrow. Any intestinal obstruction in your dog’s digestive tract requires an immediate vet visit, x-rays or an ultrasound to locate the obstruction, and possibly surgery to remove the cob.
Signs of cob ingestion are:
- Loss of appetite
- Abdominal discomfort
If you want to give them corn on the cob leftovers, scrape the cob with the blunt side of a knife to release the kernels. Give them the loose kernels rather than the cob itself. Remember, it’s best if no oils or seasonings were used on the corn.
Sweet fresh corn
Sweet corn is a great occasional snack if it’s served cooked and plain with no added salts, seasonings, or oils. Remember that your dog cannot completely digest it, but they love the taste.
Canned corn is sweet corn. If canned with no salts or oils, it’s fine as an occasional treat for your dog. Use small amounts because of the carb and sugar content.
Don’t give your dog corn if there’s diabetes or obesity problems unless it’s approved by their veterinarian.
Popcorn is the dried or cereal version of corn. If air-popped and offered with no oils or seasoning, it’s fine too. Just watch for any choking hazards and remove the unpopped kernels.
The internet is full of DIY dog treat recipes that include corn. Here are some tasty ones I found:
So, can dogs eat corn? The quick answer is yes, corn is not toxic to dogs, but it also offers very little nutritional value. As an occasional small treat, it’s fine, but anything more makes the starch and sugar content unhealthy for your pup.
The bottom line: with so many great fruits and veggies out there offering real health benefits to your dog, why waste that 10% treat allowance on something that your furry friend doesn’t really need?