Lots of fibs have been told about felines through the ages. For example, consider the popular notion that it’s supposedly healthy for cats to drink cow’s milk.

The truth is that most cats are lactose intolerant and can’t break down the sugars in milk, says Joseph Wakshlag, DMV, an assistant professor of clinical nutrition at Cornell University College of Veterinary Medicine. Kittens will — and should — drink the milk from mother cats. But once they are weaned, other milks, such as cow’s milk, are not recommended for feline diets. “Much like (some) humans, cats don’t have the enzymes to break down lactose,” Dr. Wakshlag says. “Evolutionarily, it’s not part of what cats need in terms of nutrition.” Furthermore, he adds, it can add fuel to the fire if a cat already has an upset stomach. “It’s the last thing you want to give a cat with a GI disturbance,” he says.

As with most popular myths, there’s usually some grain of truth. Over the years, farmers would sometimes put out saucers of milk for kittens. However, it would be a supplement to a meat-and-tissue diet, since the cats would catch mice in the barn, Dr. Wakshlag points out.

The spreading of myths about feline health is akin to a game of “telephone” in which someone says something and others pass it on and on. “They’re just like urban legends,” says Arden Moore, author of The Cat Behavior Answer Book (Storey 2007) and editor of Catnip magazine. “No one bothers to figure out if it’s fact or fiction,” Moore says. “They figure, ‘I’ve heard that. It must be true.’”

Sometimes the myths are harmless, such as the common belief that cats are aloof creatures — perpetuated by such fictional characters as the Cheshire Cat in Alice in Wonderland. But sometimes the tall tales can cause harm. When the myths deal with feline health and nutrition, owners like you need to take extra steps to verify what you might have read on the Internet or heard from your grandparents.

Fact or Fiction?

Here are common assumptions to help you test your cat-telligence:

Cats Always Land on Their Feet

Fact: Cats do have a “superior righting reflex” and a flexible spine. They can instinctively fall feet first, but they may also end up with broken bones from a fall, says Moore. She advises owners to check screens on windows and ledges to prevent cats from falling from high buildings.

Spaying or Neutering Will Cause a Cat to Gain Weight

Fiction: There is little scientific evidence tying the act of spaying or neutering to weight gain. The primary reason that cats gain weight is inactivity, which is more prevalent in housebound felines, Wakshlag says. However, the fact that Tomcat is no longer on the prowl — looking for love, so to speak — may reduce its overall activity level.

Pregnant Women Shouldn’t Own Cats

Fact: It is true that some cats are infected with a disease called toxoplasmosis. It’s possible for this disease to spread to humans through contact with cat litter boxes, thereby harming unborn babies. However, says Wakshlag, pregnant mothers can avoid handling cat litter. They can make sure to wash their hands thoroughly and keep them away from their mouth if they come into contact with cat waste.

Cats are Nocturnal
Fiction: Even though they have keen eyesight, cats cannot see in total darkness, according to Moore. The truth is that cats are most active in the early morning or early evening. “In the wild, cats did most of their hunting at dawn and dusk,” Moore says.

Garlic on Food Will Keep Fleas and Worms Away

Fiction: Garlic and onion have the potential to cause anemic conditions in cats, says Wakshlag. To date, no one has ever been able to prove that garlic will keep worms or fleas away.

Debunking Cat Myths

Your best bet is to exercise caution before trying out old wives’ tales on kitty. Ask your veterinarian about any myths that you’ve heard, or check out reputable cat health and research websites, such as the ones run by the Morris Animal Foundation or the Winn Feline Foundation. There is also a website run by the American Association of Feline Practitioners for veterinarians with a specialty in feline medicine. Catnip magazine, sponsored and reviewed by experts at Tufts University’s School of Veterinary Medicine, also has content available online.

Few, however, have addressed what is perhaps the most common cat myth query of all time — do felines have nine lives?

“They have but one, although they seem to be able to get themselves out of trouble quite often,” Moore says. “We only wish that they had nine lives.”