"Aging Odor" Soaps and 2-Nonenal: What the Research Shows

Soaps, body washes and sprays sold to remove “aging odor” often name one culprit: 2-nonenal. Some feature persimmon, green tea or charcoal. If you’ve started to worry about how you smell, here is what the research shows and where the marketing goes further than the evidence.

Myth: the science was made up for marketing

The chemistry comes from a 2001 study in the Journal of Investigative Dermatology¹. Researchers analyzed body odor from people aged 26 to 75 and found 2-nonenal, a compound with a greasy, grassy smell, only in people 40 or older. Its levels tracked with certain skin oils and oxidized fats that also rose with age. The authors suggested it may be involved in age-related changes in body odor.¹

So 2-nonenal is a published finding. But the study was small, and later research hasn’t settled how much it matters.

Myth: older people smell worse

In a 2012 study, 41 young adults smelled body odor samples from people aged 20 to 30, 45 to 55 and 75 to 95. They could pick out the oldest group, but they rated that odor as less intense and less unpleasant than the samples from younger and middle-aged donors.²

In other words, scent may change with age, but the study didn’t find it became more offensive.

Myth: these soaps are proven to remove it

Much of the research on removing 2-nonenal involves laboratory tests, such as extracts that capture the compound or protect skin cells in a dish.³ Lab results like these don’t show that a soap will change how you smell to other people. Look for studies in people, not just lab claims.

What does help with body odor

• Wash daily with a gentle cleanser, paying attention to skin folds, the scalp, behind the ears and the back of the neck.
• Change and wash clothing, bedding and towels often. Odor can cling to fabrics.
• Choose breathable fabrics if you sweat more at night or with hot flashes.

Our articles on odor-control body wash and why you might still smell after showering cover more steps.

When a new smell needs a doctor

A sudden or unusual change in body odor, breath or urine smell can sometimes point to a medical problem, a medicine side effect or an infection. Mention it to your clinician, especially along with other new symptoms like increased thirst, weight changes or fatigue.

Try: “My body odor seems different over the past few months, even though my routine hasn’t changed. Could a medicine or health condition explain it?”

Arms Up includes a Fresh Log and a zone-by-zone match. Use them to track products, fabrics and odor changes by body area, and bring the log to your appointment. See the book.