Teen sweat has distinct chemical make-up with notes of musk and urine

Teenagers appear to produce chemicals in their sweat that lead to body odour with notes of urine, musk or sandalwood. Being aware of these chemicals could lead to more effective means of odour control, such as better deodorants.

The chemical compounds in sweat are volatile, meaning they easily turn into gas, which we perceive as smells. The hormonal changes that occur during puberty are associated with an increase in body odour.

Helene Loos at the Friedrich-Alexander University in Germany and her colleagues looked into how body odour changes between early childhood and adolescence.

The team recruited 18 children aged up to 3 years old and 18 teenagers aged 14 to 18. They all washed with a fragrance-free gel before going to sleep with cotton pads sewn into the armpits of their clothing.

Next, the researchers extracted the chemical compounds absorbed by the pads and used a technique called mass spectrometry to identify them. They then used a process called gas chromatography and a trained assessor to detect odorous chemicals. “The human nose is used as a detector,” says Loos.

Overall, the chemicals responsible for the two groups’ body odour were similar, but those collected from the teenagers contained higher levels of several carboxylic acids, which the assessor described as “cheesy”, “musty” and “earthy”.

The researchers also identified two steroids that were exclusive to the teenage samples, which smelled of “urine and musk” and “sandalwood and musk”, respectively. The chemical differences between teenage and infant body odour may be why infants are generally considered more pleasant smelling, they write.

Further research into the scents we produce at different ages may help scientists develop more effective means of odour control, says Loos.

But Andreas Natsch at the fragrance manufacturer Givaudan in Switzerland points out that the study only evaluated body odour over one night. “The more pungent odours of adults develop upon emotional or physical stress,” he says.