I stayed out of a lot of trouble as a teenager because my mother has the nose of a bloodhound.
She could tell whom I had been hanging out with, what we had been doing and where we had been as soon as I walked in the door.
Surely, this was some kind of super human power? Perhaps my mother made a deal with an unknown entity to ensure she always knew what I was doing?
Nope, it's just science.
In fact, it's the same reason why so many of the guys you went to high school with smelled so badly. I used to think, "Surely, they can't possible not realize they reek."
Apparently, they do not realize they reek -- because teenagers can't smell sweat.
Researchers from Aarhus University in Denmark tested dozens of odors on 410 people under the age of 50.
Adolescents were less likely to smell sweat, cigarette smoke and soap -- but their noses were hyper sensitive to junk food and ketchup.
While people of all ages could detect powerful smells like gasoline, coffee and fish, it was adults who could pinpoint herbs, spices, and basic foods like bread and lemon.
Numbers-wise, 97 percent of older people could detect cigarette smoke, and 92 percent could detect sweat. Meanwhile, 10 percent of younger people couldn't identify those smells.
However, when it came to junk food, the youth truly shined: 81 percent could pick out cola while only 72 percent of adults could.
Meanwhile, 10 percent more of young people could find ketchup and 64 percent of teens could identify cotton candy while only 39 percent of adults could.
In addition, 58 percent of younger people could detect marshmallows while only 32 percent of adults could.
This may explain why teens don't realize just how disgusting their rooms smell -- they may need to become accustomed to odors over time before they are able to register them.
Alexander Fjaelstad, the lead author and assistant lecturer at the university's Flavor Institute, said,
Our findings in adolescents are in line with the hypothesis that children may lack odor-specific knowledge which accumulates throughout life. Though odors are potent triggers of autobiographical memories from as far back as the first decade of life — and in a way closely linked to memory — the ability to name odors is an acquired skill that takes years to master.
Side note for the teens: Febreze-ing your clothes isn't going to mask your smoke smell, either.