Why do babies smell so good?

Why we love that new-baby smell. Photo: Getty Images

If you’ve ever been seized by the urge to press your nose against a newborn’s head and take long, deep sniffs, hey, we hear you. The slightly sweet smell of an infant is one of the most wonderful scents in the world.

It’s so appealing, the fragrance brand Demeter even recently released a “new baby”-scented perfume, and cosmetics brands always use “baby fresh” to describe mild, pleasing fragrances.

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The universal appeal of new-baby smell begs the question: What exactly causes it? Turns out, no one knows. “One theory is that it comes from chemicals secreted from a baby’s sweat glands,” says Dr. George Pret. Since it only lasts a few weeks, it could be influenced by the baby’s metabolism, which changes when infants begin eating and drinking and no longer get their sustenance through a cord attached to their mom.

Another possibility: It stems from the whitish, waxy gunk (vernix caseosa) that coats the skin of a newborn who has just left the birth canal and made his entry into the world. It’s usually washed off immediately, but the odor might linger on the skin, says Preti.

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Whatever the cause, it appears to be all part of nature’s clever plan to make us instantly fall in love with these needy, totally dependent creatures. “The scent helps mothers recognise and bond with their offspring,” says Preti.

“Research shows that when a mother smells her baby, the pleasure center of her brain lights up.” Translation: Mother Nature wants mum to feel a sense of reward when she spends time with her bambino.

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New-baby smell isn't the only way evolution has primed us to want to love and nurture babies. “Big eyes, a rosy glow, rolls of fat, our brains are hard-wired to recognise these features as appealing, compelling us to become attached to newborns and want to help them survive,” says Dr. Helen Fisher, a biological anthropologist and professor at Rutgers University.

“A human baby is extremely vulnerable, and if we didn’t adapt to find them irresistible, we wouldn’t feel a pull to take care of them and they would die—and soon humans would die out, too.” Who knew a baby's scent (and its other appealing characteristics) were so integral to human survival?