As people grow older, their bodies naturally undergo many biological and chemical changes. One lesser-known but increasingly discussed change involves alterations in skin chemistry that can lead to a distinct body odor often associated with aging. This scent is commonly described as musty, greasy, or similar to the smell of old books. Scientists have identified the primary cause of this phenomenon as the buildup of a compound known as 2-nonenal.

2-nonenal is produced through a biological process called lipid peroxidation, which occurs when fats on the skin’s surface break down over time. As the body ages, the skin produces fewer natural antioxidants, making it more vulnerable to oxidative stress. According to dermatological research published in journals such as The Journal of Investigative Dermatology, this decrease in antioxidant protection allows fatty acids to oxidize more easily, resulting in the formation of 2-nonenal. Unlike typical sweat-related odors, this compound is not water-soluble, which makes it particularly difficult to remove with standard soaps or regular hygiene routines.

Scientific studies show that the presence of 2-nonenal increases significantly with age. Research conducted by the Japanese Society of Anti-Aging Medicine revealed that approximately 69% of participants aged 40 and older had measurable levels of 2-nonenal on their skin, while the compound was virtually undetectable in younger individuals. This finding helps explain why age-related body odor is not simply a matter of cleanliness but rather a natural biochemical change associated with aging skin.

Experts from organizations such as the American Academy of Dermatology (AAD) and Harvard Medical School emphasize that while this odor is a normal part of aging, it can still be managed. Lifestyle choices play an important role in reducing oxidative stress in the body. Diets rich in antioxidants—such as those found in fruits, vegetables, green tea, and whole grains—can help support the skin’s natural defense mechanisms. Antioxidants work by neutralizing free radicals, thereby slowing down lipid peroxidation and limiting the production of 2-nonenal.

In addition to dietary changes, specialized skincare products may also help address age-related body odor. Studies published in The Journal of Cosmetic Dermatology suggest that skincare products containing persimmon extract are particularly effective. Persimmons are rich in tannins, which can bind to and neutralize 2-nonenal, reducing its odor on the skin. Unlike conventional deodorants that mainly mask smells, these products target the compound itself while promoting overall skin health.

In conclusion, age-related body odor is a scientifically recognized condition linked to changes in skin chemistry rather than poor hygiene. Understanding the role of 2-nonenal allows individuals to take informed steps to manage this natural process. Through a combination of antioxidant-rich nutrition, proper skincare, and targeted products, it is possible to minimize unwanted odors and maintain healthy, comfortable skin well into later life.