We know why cats knead. But here's why humans love it so much.

Max Branch's seven pet cats turn his Brooklyn, New York, home into a biscuit-making factory every day, working hard at their jobs kneading away.

Cat owners and cat lovers on Instagram and TikTok have long recognized cats' impeccable dough-working skills − specifically, how the animals press their paws into their favorite soft surfaces, appearing to knead bread or biscuits. Cats first knead as kitten when they're suckling on their mother, said Wailani Sung, a cat behaviorist who helped make the 2022 Netflix documentary Inside the Mind of a Cat. But most cats continue to knead blankets and pillows for the rest of their life, to the delight of humans.

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"In some ways, a pet is like a little alien you have in your home," said Branch, whose cats are all foster-fails. "And this is a strange behavior that ends up being endearing in its oddity."

Experts say humans are rightfully obsessed with this feline behavior because it looks so cute and so serious at the same time. On social media, videos of cats wearing baker's hats and pressing their paws into pillows and blankets have garnered thousands of likes.

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Why do cats knead?

Kittens knead their mother's mammary glands, or breasts, while nursing, likely to aid the release of milk. Animal experts call this process "milk let down," said Sung, who is based in Walnut Creek, California. Adult cats make the same motion, and appear laser-focused as they press one paw after the other into a soft surface, with their toes and claws extending during each push.

Many owners say their cat is "making biscuits" when they do this, Sung said.

"The repetitive motion of their paws − I swear, if we could put a piece of dough underneath their paws, they could knead it," Sung said.

Cat owners can encourage kneading behavior by providing soft fluffy blankets and other cozy surfaces, Branch said.

"Anything that kind of mimics a mom cat's belly," he said.

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Kneading likely calms cats, or signals a happy kitty

Grown cats likely knead because it's a feel-good behavior, and their owners feel the positivity too, Branch said.

"We find it appealing because it is something they typically do when they're very happy, or when they're looking for comfort from us, which are the primary reasons we have pets," Branch said.

Adult cats can knead into a pile of laundry on the couch when they're feeling anxious and are trying to calm themselves, Sung said. Other cats may only knead when they feel comfortable and secure, in which case kneading signals they're happy, she said.

"We think that for adult cats, part of the behavior is it's a comforting experience," Sung said. "They're having flashbacks of, 'Oh, when I was a kitten I was kneading, and it felt good.'"

Kneading could also help spread cats' scent from the scent glands on their paws to their favorite surfaces, Sung said.

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Max Branch fostered John Junior, but the cat was never adopted due to his health issues. These days, John Junior loves to be around people and knead his paws into them, including while they're asleep, Branch said.
Max Branch fostered John Junior, but the cat was never adopted due to his health issues. These days, John Junior loves to be around people and knead his paws into them, including while they're asleep, Branch said.

Some cats will hold a corner of a blanket or pillow in their mouth while kneading their paws into the surface, another indication that the behavior stems from when they suckled on their mother's teat, Sung said. Some cats, like Sung's white and gray cat Olly, also drool while they knead.

"They look very blissed out and happy," Branch said. "The fact they also look very busy is pretty cute."

Ouch! Cats also knead their owners

Some cats also knead into their favorite people.

Sung's lynx point Siamese named Jaz liked to knead into Sung's throat while she slept, and Branch's "toxic extrovert" cat John Junior kneads into people's cheeks, he said.

But the intensity is your cat's way of showing "that they feel comfortable with you and that they see you as part of their family," Branch said.

Just remember to trim your cat's nails to avoid unwanted scratches, Sung said.

"They're so intense about it, like, 'I got to make the biscuits, I got to!,'" Sung said. "That's what people laugh about, because it's a cute behavior and they are so intense about it."

This article originally appeared on USA TODAY: We've all seen a cat 'make biscuits.' Here's why humans love it so.