Body odor has been a subject of interest since olden times. The attention body odor still gets is fascinating especially when an intriguing study titled 'The Smell of Age: Perception and Discrimination of Body Odors of Different Ages' by Dr. Johan Lundström and colleagues, Monell University, Philadelphia, shows that the smell of older people is 'less intense and less unpleasant than body odors originating from Young and Middle-age donors'. Dr. Lundström shares more details of his study with Medindia.
Q.In the study conducted, did the weight of the person have any impact on body odor?
AdvertisementA. No, subject groups were matched for general health, which included the BMI. It was not clear in the paper since it fell within the general screening category. However, it is something we routinely do.
Q.Under warm temperatures, people who weigh more tend to sweat more, would the amount of sweat secretion change the impression of body odor?
A. Yes, the more you sweat the more body odor you tend to emit. Also, if a person is obese and has skin flaps, body odor accumulates under the 'flaps' and becomes a breeding ground for bacteria.
Q.What were the selection criteria for participants of the study who were asked to evaluate the odors?
A. The general health requirements are described in the article. A state of good general health, good olfactory senses, no history of head injury and non-smokers were our selection criteria. Fifty percent of our subjects were students from UPENN or DREXEL University and the other fifty percent were representatives of the local population, which is predominantly African-American. We did not add race or ethnicity as part of our criteria because that would have been too many experimental factors.
Q.During the study, what kind of diet was prescribed? Did you experiment with the diet to see how that might affect body odor?
A. Volunteers were asked to refrain from eating spicy food and foods that we know would affect a person's body odor such as garlic, asparagus, certain spices and of course food additives.
Q.On an average day, people use perfumes, talc, deodorants, how do you think that would alter the results of your current study on body odor?
A. We have data (yet to be published) demonstrating that the chemosignals are not affected by deodorants and perfumes, however an antiperspirant might. In this case, allowing people to use perfume of their choice would have biased the data since these tend to be age-dependent preferences.
Q.Why were sexual preferences a factor?
A. Previous studies (see studies by Dr. Charles Wysocki and Dr. Ivanka Savic) have demonstrated that sexual preference does affect not only odor preference but a person's body odor itself.
Q.Three age groups were selected, all of them were adults, if the comparison should be between body odor of old people to that of infants (most of them have lactic smell) how would the results fare?
A. I believe that the discrimination performance would be even greater since infants tend to have a very characteristic odor.
The study conducted by Dr Johan Lundström does make interesting reading and can be accessed at http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0038110