Most people expect their skin to change with age. Fewer expect their body scent to change too. Yet many adults notice a new odor sometime after 40, even though their shower routine is exactly the same.
The short answer
One compound researchers associate with this change is 2-nonenal. It is an unsaturated aldehyde often described as greasy or grassy. A landmark study detected it in the body odor of adults aged 40 and older, while a later study also found that skin emissions of 2-nonenal increase with age in both men and women.
Where does it come from?
Your skin naturally contains lipids—oils that help support its barrier. As the body ages, some of these lipids can oxidize. That process can form compounds including 2-nonenal. This is different from the familiar odor created when bacteria break down sweat.
Why does it seem persistent?
Because the compound is associated with skin oils, the scent may cling to the body and transfer to collars, sleepwear, towels or bedding. That is why simply applying more deodorant or fragrance may not address the whole issue.
What can you do?
A useful routine starts with consistent full-body washing, fresh clothing and clean fabrics. Persimmon-based soap is a popular targeted option because persimmon contains tannins—plant compounds that can interact with odor molecules during cleansing.
The goal is not to scrub harder. Gentle, regular washing and good fabric care are usually more sensible than over-washing, which can leave skin uncomfortable.
When to ask a professional
Aging odor develops gradually. A sudden, strong or unexplained change may have another cause, so it is worth discussing with a healthcare professional.
Sources: Haze et al., Journal of Investigative Dermatology (2001); Toyoshima et al., Journal of Dermatology (2016). Educational information only.