Can Dogs Be Lactose Intolerant?

It’s no secret that dogs love human food. For many pet owners, it’s a constant battle to keep their pups out of the fridge and off the table.

Among dogs’ favorite treats is a stolen lick of ice cream or piece of cheese, but when it comes to milk and dairy products, owners should tread carefully, as dogs, like their humans, can be lactose intolerant.

Each dog's tolerance for dairy is unique, explains Dr. Rachel Barrack of Animal Acupuncture in New York City. Some can happily lap up a bowl of milk without the slightest issue, while for others, even digesting a small piece of cheddar will come with unpleasant gastric distress.

Luckily, milk is not an important part of a balanced doggy diet.

“Dairy products are not toxic to dogs; however, they are not necessary in their diet and may cause undue discomfort to your pet,” Barrack tells The Dodo. “Well-balanced dog food will contain all the calcium requirements your dog needs.”

While a puppy’s first food is her mother’s milk, once weaned, she no longer needs milk in order to thrive. “Just like in humans, dogs lose their ability to digest lactose as they age due to decreased production of a digestive enzyme called lactase,” Barrack explains. “As they grow, different dogs (and people) are able to tolerate dairy well, while others cannot.”

Puppies are born with higher levels of lactase, the enzyme needed to break down the sugars in milk, but those without access to their mother’s milk should never be given cow’s milk as a substitute, explains Barrack, as cow’s milk is higher in lactose than a dog’s.

If your dog suffers from a degree of lactose intolerance, the signs will be all too clear. Pups with difficulty digesting dairy may experience gastric issues including abdominal pain, gas, bloating, nausea, vomiting and diarrhea. Unfortunately, there are no dog-friendly lactose intolerance medications to help your pup with these unpleasant symptoms.

Besides the potentially messy results of giving your dog dairy products, there is one other important thing to consider before sharing human foods with a pet.

While dairy itself is nontoxic, certain ice cream flavors contain chocolate, raisins or macadamia nuts which can be harmful to dogs, notes Barrack. Additionally, pet owners should be cautious when it comes to frosty treats, as some frozen yogurts contain artificial sweeteners such as xylitol, which can also be toxic to dogs.

If your dog is a superstar when it comes to digesting dairy, Barrack recommends keeping the sharing to a minimum and sticking to simple flavors. “If your dog tolerates dairy products and you really want to share, stick with vanilla ice cream or very small quantities of cheese,” she says.

Otherwise, you don’t have to feel guilty about keeping the ice cream cone all for yourself.