Paper or plastic? If you asked a cat, they would say plastic 90% of the time (the missing 10% is because the appeal of hiding in a paper bag should not be underestimated). Have you ever set your groceries down only to come back to a kitchen that has been transformed into the meeting place for all of the plastic bag lovers in your home? The sound of little sandpaper tongues sliding along sleek plastic fills the air as you think to yourself “What is going on.”
The good news: your cat is not crazy. Plastic bag licking is a common habit among cats. The bad news: there’s no definite answer as to why cats lick plastic bags. But have no fear, our collections of vets have come together to create a list of the most likely reasons why cats lick plastic bags.
Perhaps the most obvious answer to the great plastic bag licking debate could be: because they smell good! Yes, we are serious. Plastic bags are traditionally composed of ethylene or ethene polymers and are made of one of three basic types of plastic: high-density polyethylene (HDPE), low-density polyethylene (LDPE), or linear low-density polyethylene (LLDPE). Grocery bags are traditionally made of HDPE. HDPE is incredibly absorbent which allows for the plastic grocery bags we use while shopping to absorb the smells of the objects that they carry. Don’t believe us? Try placing a rotisserie chicken in a bag for 20 minutes and then removing it and placing that plastic bag somewhere your cat can get it. We bet that your cat will probably wander over and give it a lick within 10 minutes.
Plastic bags are often treated with something called stearates. Stearates is a salt of ester of stearic acid. Stearic acid is a saturated fatty acid that can be found in animals, vegetables, and oils. Stearic acid is white and has the ability to float on water. Stearic acid has been verified to be of low concern based on experimental and modeled data provided by the EPA. Additionally stearic acid is nontoxic. This fatty acid can taste exquisite to your kitty.
Many believe, our vets included, that cats lick plastic bags because the created sound sounds like little rodents. To be more precise, our vets believe that this sound mimics the unique sound of rodents scurrying in leaves or grass. This action is similar to that of you playing ambient sounds such as thunderstorms or rain that you find calming and evoke positive feelings. The thought of catching some mice evokes positive feelings for cats.
Plastic bags are undeniably bad for our planet. Standard plastic bags are not biodegradable, plus, tens of thousands of whales, birds, and turtles are killed every year from plastic bag litter. With the amount of plastic in our landfills and oceans growing by the day, scientists have been searching for a plastic bag alternative for years. Enter corn plastic. Corn plastic, also known as PLA, has been adopted by some big names like Wal-Mart. Corn plastic is as the name implies made of corn – usually, a variation called Number 2 Yellow Dent that is traditionally used to feed animals. Your cat probably doesn’t care if you’re for or against corn plastic, she just likes it when you bring home plastic bags from Wal-Mart because they taste good.
Pica is a term used for the behavior of eating non-food materials. Pica can happen to any cat and is sometimes seen more frequently in cats who were weaned too early. Some cats with pica will suck on items whereas others will eat items completely. Most commonly, cats with pica suck on soft items like wool, fleece, or stuffed animals, but some cats do focus on other items like plastic grocery bags. Pica can be caused by a multitude of avenues; if you suspect that your cat is suffering from pica talk to your vet today.
Most plastic bags are made with slip agents to reduce the friction in the material; these slip agents are often made of beef tallow. Tallow is very nutrient dense because it contains conjugated linoleic acid, antioxidants, fat-soluble vitamins, and omega-3 fatty acids. If you’re wondering what tallow is, the Ultimate Paleo Guide provides an excellent comparison. “Pork is to lard as beef is to tallow.” So your cat may be licking your plastic bags for that yummy beef fat.
The Unknown Answer
Vets from around the world are still scratching their heads in question as to why cats lick plastic bags. Is it one of the reasons we listed above; or is it something different altogether? We may never know. Our veterinarians have made their best guesses, and we’ll continue to search for an answer. In the meantime be careful of letting your cats play with plastic of any kind. Swallowing plastic can be harmful or deadly; additionally, suffocation and strangulation are also concerns where plastic is concerned for your cat. Make sure that your cat is being safe around plastic at all times.