Few parents would describe the odors emanating from their teenage children as reminiscent of sandalwood. But one of the distinct components of teen body odor is a compound that causes that warm, woody scent, according to a small new study that compared the smells of teens with those of infants and toddlers.
Unfortunately, that’s exactly where the good news for teenagers (and their parents) ended. Although there were many similarities between the chemicals coming from the teenagers and young children, the differences tended to favor the younger children, whose body odor samples had higher levels of a flower-scented compound. Adolescents, on the other hand, produced a compound that smelled like sweat and urine and had higher levels of substances described as smelling like cheese, musty and “goat-like.”
The authors of the study, which was published in the journal Communications Chemistry on Thursday, did not go so far as to say that the results proved that teenagers smelled worse than babies. But the differences they documented “may contribute to the less pleasant body odor in teenagers,” said Diana Usienko, who conducted the study as part of her doctoral research at the University of Erlangen-Nuremberg in Germany. (She is now a researcher at RISE Research Institutes in Sweden.)
Body odor is a complex mixture of airborne chemicals, many of which are produced when sweat and sebum, an oily substance normally secreted through hair follicles, are broken down by skin microbes or react with other compounds in the air. The differences in smell between young children and teenagers probably stem from puberty-induced changes in sweat and sebum production, the researchers said.
The study was based on samples from 18 young children, aged 3 years or younger, and 18 teenagers who had gone through puberty. To collect the body odor samples, the scientists sewed small cotton patches to the armpits of T-shirts and suits, which the children and teenagers wore during the night. (Participants were asked to refrain from using scented hygiene products and from eating highly aromatic foods, such as onions and garlic, for 48 hours beforehand.)
In the laboratory, the scientists extracted and analyzed the chemical compounds that had permeated the patches by collecting samples from several children in the same age group.
Odor samples from young children contained most of the same chemical components as samples from teenagers, the researchers found.
But there were two compounds, both steroids, that were present only in the adolescent samples. Sweat glands that aren’t activated until puberty secrete precursors to these compounds, which skin microbes convert into said steroids.
Characterization of fragrances is difficult. “There is no universal consensus on how to describe odors,” said Helene Loos, who is a fragrance and odor researcher at the University of Erlangen-Nuremberg and an author of the new paper.
Odor experts at the university had previously developed a standard vocabulary for characterizing the odors of different compounds, with an initial focus on food aromas. “We have now extended this language of taste to substances that appear in body odors,” Dr Los said.
Careful sniffs of the teenagers’ steroids revealed that one of the compounds smelled of sandalwood and musk. The other also had musk-like qualities, with the unfortunate additions of sweat and urine-like scents.
The teenagers also had higher levels of compounds called carboxylic acids. They included musty, cheesy and goaty substances – as well as some with less offensive aromas, variously described as earthy, fruity or waxy.
Carboxylic acids are contained in sebum, which also contains other compounds that can be converted to carboxylic acids by microbes or various chemical processes. Sebum production increases during puberty.
The researchers think that, combined, the two musky steroids plus the higher levels of carboxylic acids may explain why teenage body odor can be bothersome to some people.
“I think it’s difficult to determine that one smell is always pleasant for everyone and to say that another smell is always unpleasant for every person,” Ms. Owsienko said. “So that’s an assumption on our part.”
