We’ve all noticed it.  The room that Granny Jean sleeps in when she comes for her week long visits continues to be inhabited by her smell long after she has gone home.  Or what about the elderly couple you stand behind in the line at the pharmacy.  In fact you could be blindfolded and be able to identify what decade of their life that that couple is experiencing.  Most would describe the odor the same- not unpleasant, but distinctive for sure.

There are many theories as to why this old person smell is a very real thing.  Some are linked to the lack of ability of the elderly to take care of their basic hygiene needs.  Older folks also tend to be colder.  They have their heat running more which leaves their living environment stuffy.  Additionally, because they don’t sweat  much they often re-wear their clothing- getting several days out of an outfit. As we age we produce less saliva.  That leads to dry mouth and a breeding ground for bacteria which can be very odiferous.  Finally the smell of medicine is, for obvious reasons, often prevalent on the skin of the elderly.

Though all these things may be legitimate contributors to what we think of as “old person smell,” scientist have found a much more specific and equally significant offender.  It is a chemical compound called 2-nonenal.  It comes from a breakdown of the secretions from skin glands.

This finding was discovered by a sensory neuroscientist named Johan Lundström of the Monell Chemical Senses Center in Philadelphia. He and his group of researchers analyzed the secretions in people aging from 26 to 75.  The findings were that in the subjects over 40 years old there was an increase in 2-nonenal, and it increased exponentially with age.  (http://healthland.time.com/2012/05/31/old-person-smell-really-exists-scientists-say/)

Just remember that next time old Uncle Fred comes to town, it’s not his fault he smells that way. It’s his 2-nonenal!