As Our Skin Sags With Age, So Do Our Bones

Enlarge this image toggle caption Nate Lavey/NPR Nate Lavey/NPR

Dr. Howard Langstein does face-lifts for a living, and he's the first to say that there are some facial droops that even repeated nips and tucks won't fix.

"If you simply pull the skin tight, it has a pretty unnatural look," says Langstein, a plastic surgeon at the University of Rochester. "The look we're born with -- cherubic face, puffy cheeks -- that's the look of youth."

To figure out why so many people with face-lifts look "windswept" instead of youthful, Langstein and a colleague, medical resident Dr. Robert Shaw, collected three-dimensional CT scans of the skulls of about 60 adults. The idea was to look deep beneath the sagging skin and soft tissue, and focus instead on the underlying bone. When they grouped the scans according to age -- young, middle age, and 65 and older-- and took careful measurements of the various dimensions of the face, a pattern emerged: It's not just skin that droops with age, they discovered. Facial bones shift and wither with time, too.

Enlarge this image toggle caption University of Rochester Medical Center University of Rochester Medical Center

"We saw changes around the eye, and then in the cheek area and in the jaw," says Langstein. "And if you think about it, it kind of makes sense. When people age, the eyes appear hollow, deep-set. And, in fact, that's what we found. The cheek bones right beneath the eye socket descend somewhat and come back in. As a result, they don't give as much support to the lower eyelid."

The same was true of the jaw, he says. "If you think about the aged face, there's sort of a lack of definition in the jaw line. And that's what we saw in the CT scans." As the jawbone became thinner, the chin receded, so that the scans of the oldest people looked a little slack-jawed.

"It's one of those things that, in retrospect, you sort of say, 'Duh, I should have known that!' " says Langstein. "Nothing stays the same on the body. Everything ages."

The Skeletal Evidence

Langstein could have asked David Hunt. Hunt works as a physical anthropologist at the Smithsonian's Natural History Museum in Washington, D.C., where he oversees the roughly 30,000 human skeletons in the Smithsonian's collection.

When you see that many bones, Hunt says, you get a pretty good sense of how bone changes over time. He points to one classic-looking skeleton, dangling from a stand in his lab. With its chiseled jaw and perfect teeth, the skeleton is clearly a young adult, he says. In our high-flying 20s, our insides, as well as our outsides, look their best.

Enlarge this image toggle caption Nate Lavey/NPR Nate Lavey/NPR

Hunt says a 20-year-old's bone is "really pretty stuff. It's smooth, and it's solid, and it's hard, and it's dense." But bone is not just a hunk of calcium; it's alive and constantly, throughout life, being eaten away and rebuilt, bit by bit. In fact, every dozen years or so, each of us has a whole new skeleton. That's good, Hunt says. And bad.

By middle age, the texture of that bone is rougher. Eye sockets start to sink, the jaw recedes. You can get all the exercise and drink all the milk you want, Hunt says, and you're still going to get some bone loss in your face, simply from aging.

"Nothing stops it," he says. But the guy who's seen 30,000 skeletons does have some tips for how to slow down that facial bone droop: Hang on to your teeth.

Hunt olds up a skinny, toothless jawbone that looks like the yellowing, withered-away blade of an old ice skate.

"Mainly what you're seeing here is the impact of tooth loss," he says. "The body takes away those no-longer used sockets where the teeth used to be."

Hunt says that thanks to decades of better dental care, antibiotics and fluoride, the teeth and skulls of baby boomers look a lot younger than those of our grandparents in middle age. Yet another reason to keep flossing -- and smile.