Just how do you go about proving this? Johan Lundström and his colleagues at the Monell Chemical Sense Center in Philadelphia collected the underarm scents of people in three age groups: 20-30 years old, 45-55 years old and people 75-95 years old. Then they had other young people (ages 20-30) sniff the armpit pads.
The researchers had the participants wear the same T-shirt to bed for five nights. The shirts and sheets had been washed with scent-free detergent and the participants washed with scent-free soap every night. They also agreed not to smoke, drink alcohol or eat foods that are known to cause body odors. Special pads were sewn into the underarms of the T-shirts to collect their body’s scent.
The people doing the sniffing rated the pads on pleasantness and intensity and had to guess which of two odors came from older participants. Then they were instructed to label all of the armpit pads by age category.
Although they had trouble distinguishing between the young and middle aged people’s pads, they were able to correctly determine which came from old people more often than would be randomly expected. Evaluators used words such as “earthy” and “mild, like stale water” to describe the odors of older people.
“These elderly odors were very distinct and easy to group together,” says Lundström. The study found that the armpit pads from old men were rated the most pleasant, especially compared with middle-aged men, although the odors from old women were rated behind those of middle-aged women.
Lundström and his colleagues concluded that if you associate the scent of old people with something negative, it is likely to have more to do with context than the actual odor.
The study was reported online May 30, 2012 in PLoS ONE.
This article was originally published in Pathways Residential Care Journal - Issue 4. To download this issue in PDF format, or past issues, visit our newsletter archives online at www.pathwayshealth.org/publications.