The smell of old people

When most people talk about “old people smell,” they’re complaining about something unpleasant. But in a new study, scientists report that the scent of the elderly isn’t that bad. In fact, it’s rather pleasant, at least compared to the intense odor of a middle-aged man. Volunteer judges used words like “earthy” or “mild” to describe the elderly scent.

Psychologist Johan Lundström of the Monell Chemical Senses Center in Philadelphia led the new study. At his laboratory, Lundström and his team study how the brain helps a person detect chemicals through tasting or smelling.

In the new study, the scientists enlisted the help of men and women who didn’t mind sharing their scents. The participants were divided by age into three groups of 12 to 16 volunteers. One included people 20 to 30 years old. A middle-aged group included people 45 to 55 years old. The oldest recruits were 75 to 95 years old.

For five nights, each participant showered with odor-free soap before bed. Every night, they put on the same T-shirt — one with absorbent pads sewn in the underarm area. The people slept in beds with linens that had been laundered with fragrance-free soap. And throughout the experiment, no one smoked or consumed beverages or foods that would impart a smell to the body.

After the last night, the armpit pads were collected and sniffed by other volunteers, all 20 to 30 years old. They rated the pads’ pleasantness and smell intensity. Scientists also asked these sniffers to group the pads by how old they thought the wearers had been.

The sniffers had a hard time identifying a difference between scents of young or middle-aged individuals. But they fairly easily figured out which pads had been worn by senior citizens.

“These elderly odors were very distinct and easy to group together,” Lundström told Science News.

The old men’s odors were actually rated the most pleasant of all the male odors, Lundström and his colleagues reported, especially when compared to the intense smells of middle-aged men. Middle-aged women’s smells were rated more pleasant than those of elderly women.

The recipe for body odor is complicated and scientists don’t know the exact ingredients. In general, glands in the skin produce chemicals, and bacteria that live on the skin add to this mix. These ingredients also interact and change as a person ages, further altering the smell. But even if scientists don’t completely understand the process, our noses seem to.

Power words

biology The study of life.

behavior The way in which an animal or person acts in response to a particular situation or action.