New Scientist, 03 July 1999
smell from an old lady's armpits can raise your spirits, a scientist in
Pennsylvania claims. Her work also suggests that in contrast, the scent
of a young child does nothing to improve your mood.
using animals have shown that smell is vital for conveying information.
Rodents can detect and transmit fear through smell, for instance, and
animals often identify a high-ranking member of a group by its smell. A
recent study has shown that people can distinguish the body odour of
both happy and fearful people (This Week, 1 May, p 25). But the impact
of body odour on people's moods has hardly been explored at all.
Chen of the Monell Chemical Senses Center in Philadelphia hoped to find
out more. So she recruited 30 volunteers in six different categories:
girls and boys aged between three and eight, young adult women and men
in their early twenties and elderly women and men in their seventies.
The volunteers all gave samples of their body odour by strapping a
gauze pad under each armpit and keeping it there for 10 hours.
participants were not allowed to use any perfumes or deodorants, or eat
strong-smelling foods, in the four days before the samples were
collected. They could shower, but only with unscented soap and shampoo.
Odours were also collected from the homes of all the donors and
combined into a neutral control smell.
Chen then asked 308
university students to complete a 36-part questionnaire that assessed
how positive their mood was. Then they smelled the gauze pads from one
of the six categories of people -- without being told what the smells
were. After this, the students answered the questionnaire a second
time, this time with the questions shuffled around.
had inhaled the samples taken from old women's armpits responded
significantly more positively, Chen found. "Old women had an uplifting
effect," she says. The smell of young men, on the other hand, produced
a depressive effect. In general, the smell of older people improved
mood, as did smells from females, Chen will report in a future issue of
the journal Physiology and Behaviour.
Jeannette Haviland, of
Rutgers University in New Jersey, who also worked on the project, says
it's possible that hormones make the body odour of young people signal
aggression. But hormonal changes may make the odour of older people,
especially women, signal that they are approachable. Alternatively, it
could be that women in their golden years are generally happy, and that
their odour can transmit this mood. "The airborne chemicals that we
collected from them -- "l'eau de grandmère" -- may indicate that
state," says Haviland.