The body odor in older adults is often compared to old oil, dry grass, aged books, or clothes stored away. This phenomenon can emerge from middle age, primarily linked to 2-nonenal, a compound that forms when the skin's natural lipids oxidize, much like cooking oil exposed to air.
In younger individuals, skin regenerates rapidly and effectively limits oxidation. As people age, these protective mechanisms diminish, and the composition of skin lipids changes, facilitating a greater production of 2-nonenal. A 2016 study, which analyzed gases emitted from the skin's surface, observed an age-related increase in this compound in both men and women.
Doctor Sonal Choudhary, a dermatology lecturer at the University of Pittsburgh, states that the change typically becomes more noticeable after age 40 and is often evident from age 50. However, its intensity varies significantly among individuals, influenced by genetics, skin type, diet, current medications, health status, and living environment. Factors like sun exposure, tobacco use, and poorly ventilated areas can also intensify the lingering scent.
According to Danielle Reed, scientific director of the Monell Chemical Senses Center, 2-nonenal readily adheres to skin, clothing, and bedding. While washing can partially reduce it, complete elimination is difficult as the body consistently produces this compound. Individuals with this odor often do not perceive it themselves because the change occurs gradually, allowing the brain to adapt and disregard the familiar scent. This phenomenon is akin to a homeowner being unaware of a particular smell in their living space, while visitors immediately notice it.
A study published in PLOS One indicates that humans can identify older age groups based on body odor. In an experiment evaluating samples from three age cohorts: 20-30, 45-55, and 75-95, 41 volunteers most accurately identified the older group. Interestingly, samples from this group were perceived as milder and less unpleasant compared to the other two.
Therefore, the characteristic scent in older adults is not synonymous with an unpleasant odor; rather, it represents a natural bodily change, much like graying hair, dry skin, or wrinkles.
To mitigate this odor, older adults are advised to use mild cleansing products, change clothing, wash bedding regularly, and ensure rooms are well-ventilated. Harsh scrubbing or strong detergents should be avoided, as aging skin is often thin and vulnerable. While soaps containing persimmon extract might help lessen the scent, large-scale research has not yet confirmed their capacity to completely eliminate 2-nonenal.
If body odor undergoes a sudden, unusually strong change, or is accompanied by unexplained weight loss, fever, excessive sweating, skin lesions, or altered urine, individuals should seek medical consultation rather than attributing it solely to age.
By Ngoc Ngan (Source: HuffPost, PLOS One)
