Body odour doesn’t just tell you whether a person is taking a bath every day. According to a recently published paper in PLoS ONE journal, human beings can
The idea for the study ‘The Smell of Age: Perception and Discrimination of Body Odors of Different Ages’ came to the lead researcher Johan Lundstrom of Monell Chemical Senses Center, Philadelphia, US, when he went to a retirement home to give a lecture. He told Los Angeles Times that the smell there reminded him of a childhood smell when he visited the retirement home his mother worked at. Lundstrom decided to test whether such a smell actually existed in old people.
To get the smells, people from three age groups—20–30, 45–55, 75–95—were made to wear custom-made T-shirts with absorbent pads in the armpit for five days. Pads of people from each age group were placed in the same jar, so that the odours would get segregated by age. Forty-one volunteers (not the ones whose sweat was collected) then rated the odours based on parameters of intensity and pleasantness. For pleasantness, they were asked to make choices ranging from ‘extremely unpleasant’ to ‘extremely pleasant’; and for intensity, they had to choose from ‘no sensation’ to ‘strongest imaginable’. Additionally, they were given two odours and asked to choose which was from the older group.
The results were interesting. Most volunteers could identify the body odour of people in the 75–95 age group. They could also identify the odour of the other two age groups (20–30 and 45–55), but could not pinpoint which specific age group those odours belonged to. The results lend credence to the fact that there is something called the smell of old age. And that’s not just it. The volunteers actually rated the old-age smell more pleasant than the body odour of younger age groups.
The authors of the study wrote in their paper, ‘This experiment suggests that, akin to other animals, humans are able to discriminate age based on body odor alone and that this effect is mediated mainly by body odors emitted by individuals of old age.’