During an extended period of travel last year, my husband and I lent our house in the Ozarks to an older couple who were having work done on their own house.
We returned after a month away to a spotless house and two hostess gifts. But there was also a distinctive smell in the air: slightly stale and sweet, like the musty first whiff of strawberries in a cardboard box.
I wiped countertops and mopped floors. Still, the odour remained. Not terrible but strange and cloyingly human. Late that night I guiltily Googled, "Do old people smell?"
The answer I found was yes. Then no. And maybe …
I mentioned my question to a group of women writers, ranging from 40 to 70, and got drastically different responses. The younger women said yes, there's an odour associated with aging. But to the older women it sounded like ageism and a few took offense.
At 52, I felt a little prickly about it myself, but also in need of information. If there was anything I could do to improve my personal scent, now and in the future, I wanted to know. So I consulted two scientists from a renowned research lab and ran into the very same split.
Johan Lundstrom, a 46-year-old biologist with the Monell Chemical Research Center, says his studies confirm what Japanese researchers found in 2001: An unsaturated aldehyde called 2-nonenal is more concentrated on the skin of older people, often producing a distinctive grassy, waxy or fatty odour.
His study — admittedly small — used samples from the underarms of people from the ages of 20 to 95 and presented them to 41 participants who ranked them on intensity and unpleasantness. In addition, Lundstrom and his co-authors found that "participants were able to correctly assign age labels to body odours originating from old-age donors but not to body odours originating from other age groups."
But George Preti, a 74-year-old analytical organic chemist, also with the Monell Chemical Research Center, says his studies did not match the results found by either the Japanese group or Lundstrom's team. Preti's team used upper back and forearm samples and submitted them to gas chromatography and mass spectrometry, concluding that "no method of analysis" revealed the presence of 2-nonenal in older subjects.
"Old people actually smell less than younger ones," Preti said. "Unless you go to a nursing home, where there are hygiene issues in the mix, you're not going to find this musty, unpleasant odour everyone is talking about."
"I know what George told you," Lundstrom said. "He's wrong. His study was too narrow. He's just sensitive about this topic because he's old," he said in a tongue-in-cheek manner.
Universally, studies show that in blind "smell tests," the odour of middle-aged men is judged to be the worst — more offensive than samples from younger individuals and older ones. (Middle-aged women, despite all our fears to the contrary, smell the best.) Chemical analysis bears this out, with lower levels of sebaceous secretions in the very young and very old.
Lundstrom's study affirmed the existence of "old people smell" but stated that on average participants found it "neutral" and "not unpleasant." He believes the odour is perceived as negative largely due to context. It's similar, Lundstrom says, to the smell of fresh manure: Smelled in a stable, it's perceived as natural. But in one's bedroom it becomes disturbing and bad.
"In the Japanese study, when researchers did not tell participants what the odour was, they rated it as 'inoffensive,'" Lundstrom says. "But when they said it was from an old person, it was rated as 'nasty.'"
The bias in Japan is clear. They have a name for older person odour — kareishu — and it has a definitively negative association. A Japanese company called Mirai Clinical sells a US$16 persimmon soap bar that promises to eliminate the "offensive" smell.
Preti distrusts the science of the 2001 study. "I was 57 when the original Japanese study came out and I remember being quite offended," he said. "The group they sampled as being 'old' included people in their 40s. That's insane."
Lundstrom endorsed the Japanese findings but was leery of the industry around kareishu; he said expensive creams and soaps will not provide a fix.
"Smell has a very large subconscious component," Lundstrom said, "so masking it will not do any good. Each odour binds to a particular chemical receptor in the nose and this information will travel even through heavy perfume."
Instead, he's advised his own aging parents to stay active, air out their house frequently and wash linens and clothing regularly, even if they don't appear dirty. Other factors are harder to control, such as genetic predisposition and general health.
Preti — despite his conviction that older people smell less and better than younger ones — made many of the same recommendations.
The scientists agree that people with chronic diseases are more likely to give off odour, no matter what their age. Preti attributed this more to diet, metabolism and self-care, Lundstrom to the possibility — which he is in the process of investigating — that ongoing inflammation leads to odorous cell decay.
"Yes, that's actually somewhat reasonable," Preti said affably when presented with Lundstrom's theory. "We didn't talk about inflammatory disease, and all the subjects in my study reported they were healthy."
Both researchers mentioned that the sense of smell tends to decrease as people age, so systems of self-monitoring — such as breathing into cupped hands, or sniffing under our arms — often fail around the seventh decade of life.
"I am confident there is less odour in a healthy 80-year-old than a healthy 30-year-old," Preti went on. "But when you introduce disease or disability it gets more complicated. Believe me, I take care of someone who has had a series of strokes. That is a very different thing."
Nonenal and its sweeter-smelling cousin, nonanal, are aldehydes that were discovered in the 1920s. They've been used in small concentrations by the scent and flavour industries ever since.
"Nonanal, which is also found on the skin of older people, is called aldehyde C-9 in the perfume industry, and it was one of the magic ingredients that made Chanel No. 5," says Craig Warren, an odour consultant and former vice president and research director of the fragrance science division of Internationals Flavours and Fragrances.
"It's possible you find these aldehydes more in Japanese populations than in Americans," he said. (Preti also proposed that Japanese subjects might have higher levels of nonenal from eating fish.) "But I'm almost 80 years old and I've spent my life in odour research. If someone told me I had a particular smell I wouldn't take offense, I'd want to do something about it."
A new method for odour masking may provide the key. Warren works with an Illinois-based company called Belle Aire Creations that has developed technology to bind a chemical masking product with a distinctive odour, forming a larger molecule that is non volatile — meaning it will no longer escape from a surface and into the air.
"Nonenal would be a perfect candidate for this malodour masking technology," Warren says. "But to my knowledge no one is asking for a product to counteract this smell. The market is not driving a need."
It's possible that the topic is too sensitive for an American company, Warren says. The manufacturers of feminine hygiene spray have received complaints of sexism, so health and beauty corporations may be leery of provoking older consumers.
For now the best advice for combating age-related odour is simply to take care of yourself and your home: exercise, stay healthy and hydrated, eat clean food, open windows, launder clothing and sheets.
And don't worry about it.
I recently stopped by the home of the friends who had stayed at my house to return a few things they'd forgotten. They made tea and as we talked I noticed the same funky, sweet strawberry smell. But in their homey, pillow-strewn living room, it did not bother me.
Context, I thought. In that respect, Lundstrom was right.
Written by: Ann Bauer
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