How Much Should You Feed a Dog?

More than 50 percent of dogs in the United States are overweight, yet one of the best ways to keep them healthy is seemingly quite simple: feed them the right amount of dog food. 

However, according to Cailin Heinze, a board-certified veterinary nutritionist, a preoccupation with how much to feed our pets has led to a common mistake in the way we feed them.

“The first thing most pet owners do wrong is focus on how much volume to feed rather than paying attention to calories,” Heinze tells Mental Floss. Although pet food packaging is required to include caloric content in its feeding guide, most brands provide cup-based measurements. So if a pet owner switches dog food brands, they likely won’t recalculate the volume based on the new diet’s calorie count. They’ll just continue feeding however many cups a day they have been. 

“I can’t tell you how many clients have a pet that has gained or lost dramatic amounts of weight, and lo and behold, they were feeding a diet that was 420 calories a cup, switched to a diet that was 320 calories per cup, and fed the same amount because ‘Oh, I’ve always fed two cups a day,’” she says, “without appreciating that dog food can range from 200 to 600 calories per cup.”

In fact, “in a perfect world,” Heinze says, we wouldn’t use cups at all: “We should all feed by grams because it’s much more accurate. Are you accurately measuring two-thirds of a cup? Most don’t.”

When calculating the right caloric amount of food, “it’s absolutely dependent on the dog.” Size is a common factor, but so is breed, age, and energy level, which can be tricky to estimate. 

Heinze recommends asking your vet to perform a Body Condition Score—a management tool to assess animal nutritional status—at your next visit. From there, you can evaluate your pet at home. Pet owners should also weigh their dogs frequently so they can make subtle adjustments in food. 

“It’s one thing if you find out that they’ve gained a pound this past month so that you can just remove a few kibble a day to get them back on track,” Heinze says. “That’s much easier to do than waiting for the annual checkup and finding out they’ve gained 10 pounds and you’re now trying to get 15 percent of their body weight off.” 

Of course, it’s not just about how much pet food you should be feeding your dog. Treats—from commercial options or dental chews to pieces of banana, table scraps, or the milk from your cereal bowl—add up. Those items should account for less than 10 percent of your dog’s daily calories. Unfortunately, Heinze has found most pet owners are oblivious to not just the number of calories in treats, but how many treats they’re doling out.

“If you have a Great Dane, you’re probably OK, but if you have a Shih Tzu and you’re giving them a tablespoon of peanut butter in their Kong every day, that’s a high percentage of their daily calorie needs you’re ignoring.” 

Tracking your dog’s food in this way might seem overwhelming, but Heinze assures her clients that the payoff is worth the initial investment in a new feeding strategy. “It’s not what most pet owners are used to doing,” she says, “but once you get in the habit, it’s absolutely doable. And your dog will be healthier for it.”