You might think a trip to the groomer to get rid of some of that fur will help your dog chill out in the heat of summer. But it turns out that’s a myth.

A summer shave can actually make it harder for your dog to cool down. It can also get your pooch sunburned and aggravate his allergies.

“About 90 percent of vets say, ‘Don’t shave,’” says Bernadine Cruz, DVM, a veterinarian at the Laguna Hills Animal Hospital in California, and a member of the American Veterinary Medical Association.

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Here are four reasons not to shear your pup in summer:

1. Your dog’s coat helps keep him cool. A dog’s coat provides natural air conditioning. How? Dogs have tiny muscles connected to their hair shafts that allow the hairs to stand up and catch a breeze, which cools the dog, says Sonja Olson, DVM, an emergency veterinarian at Blue Pearl Veterinary Partners. The mechanism is similar to how humans get goose bumps, she says. The double coats of some northern breeds — Akitas, Huskies and Malamutes, for example — help insulate them from the summer heat. 

2. Fur is a natural sunscreen. The coat protects canine skin from direct contact with sunlight and UV rays that can cause sunburn and skin cancer. Dogs that have been shaved and breeds that don’t have much hair, like the Chinese Crested, actually need a dog-safe sunscreen — one that doesn’t contain zinc or PABA — on their backs and other exposed areas, Olson says. Talk to your vet about which sunscreen to use.

3. All that shag keeps allergens away. The fur acts as a natural barrier to dust mites, pollen and grasses that can cause skin allergies in dogs. Shaving the coat puts a dog’s skin in direct contact with the world, which may cause a breakout, Olson says.

4. The fur might not come back, or might grow in unevenly, after a shave. In most cases, dogs’ coats grow back completely normally, says Robert Schick, DVM, a board-certified veterinary dermatologist with Blue Pearl. “But there’s always a chance it won’t come back,” he says.

In some situations, though, there can be pros to shaving your dog, says Schick. If your dog has bad flea allergies, a summer shave might make it easier to spot fleas and could help a topical flea medicine spread more easily around the skin. “That would be a bonus,” he says.

And a dog with a very dense coat and severe inflammation from skin allergies might do better with a shave so that medicated shampoo can reach the skin, Cruz says. “In that case, I say go ahead and shave — but keep the dog out of the sun,” she says.

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Keeping Fido cool

Worried about how you’ll keep your pooch comfy without a summer shave? Here’s what to do when temperatures rise.

Remove excess fur. Brush your dog regularly and use a de-shedding tool like a FURminator to thin out the undercoat, Cruz says. “That’s good for the skin and coat,” she says.

Belly up. If you have a dog with a thick coat, you can have a groomer shave only her belly. That way, your dog can find a cool surface like a tile or stone floor and lie on it to cool down, Olson says. Leave the fur on her head, neck and back where the sun beats down, she says. And that fur that grows between your dog’s paw pads? Don’t trim it. It offers protection from hot sidewalks.

Don’t walk when it’s blazing hot. Keep summer walks short, and take them in the morning or evening to avoid the scorching sun and hot pavement, Olson says. Midday walks can put your pup at risk for heat exhaustion. “Even taking a stroll around the block at lunchtime might be too much.”

“Be smart about the heat,” Olson says. “Shaving your dog’s coat isn’t the answer.”

Allie Johnson is an award-winning freelance consumer writer with a degree in magazine journalism. She lives in Georgia with her husband and two dogs.