If you have ever been unlucky enough to get stuck on a poorly ventilated form of public transport just as a pack of high schoolers get on board after a long day, you will know that teenagers smell bad. It’s an objective fact. They stink.
We know that along with a whole host of developmental changes accompanying puberty, that distinctive teenager stench comes from a hormonal activation of sweat glands. The sweat combines with a unique microbial population to generate smells that are unique, to say the least.
But until now, the actual chemical composition of this distinctive body odor has been relatively unknown. A new study led by a team of researchers in Germany has for the first time compared the chemical composition of body odor between teenagers and infants, homing in on the exact compounds that make babies smell like flowers and teens smell like sweaty goats.
The research gathered together two cohorts – 18 infants aged between zero and three, and 18 teenagers aged between 14 and 18. Each subject slept for one night in a pre-treated cotton t-shirt with pads sown in under the arms. For 48 hours before the study night, each subject followed strict dietary and hygiene protocols, abstaining from perfumed cleaning products and refraining from eating strongly spiced foods.
The cotton pads were then analyzed using a variety of processes including gas chromatography-mass spectrometry and gas chromatography-olfactometry. From this data the researchers broke down the body odor into 42 distinct odor-active compounds.
In general the study found the chemical composition of body odor to be relatively similar between the infant group and the teenage group. However, some key quantitative differences were detected that are suggested to account for the notorious discordance in smell between the groups.
In the infants a compound known as α-isomethylionone was detected in significantly high volumes. This compound generates a violet-like odor. Another unknown “perfume-like” odor distinguished the infants from the teenagers. The researchers speculate these pleasant odors were possibly relics of perfumed detergents or cleaning products that may have persisted on the infants despite the 48-hour wash-out protocol.
The odor profile in the teenagers on the other hand was much more potent. High levels of compounds such as 4-Ethyloctanoic acid (described as smelling “goat-like”) and Dodecanoic acid (described as “wax-like”) were detected, alongside some novel compounds only found in the teenager body odor.
Two steroid compounds – 5α-androst-16-en-3-one and 5α-androst-16-en-3α-ol – were found only in the teenager samples. These compounds were variously described as having odors resembling sweat, urine, musk and sandalwood.
One of the big takeaways from the study is the speculation that the main reason infants smell better than teenagers is because of the absence of these particular steroid compounds. It is less an issue of babies smelling inherently nice but rather more that they simply don’t exude certain unpleasant smelling steroid compounds.
So there you go. That funky teenager smell is a real thing and they do smell a little like goats and urine.
The new study was published in the journal Communications Chemistry.
