As people get older, subtle changes in natural body scent can become more noticeable. While the phenomenon has long been associated with aging, scientists say there is no single explanation for the familiar musty or grassy aroma that some people associate with older adults.

Part of the answer can be found in changes that happen on the skin over time. However, lifestyle, diet, medication, surroundings and even personal memories can influence how a particular scent is produced and perceived.

Aging skin experiences predictable biochemical changes that can influence natural body odor. Importantly, this does not necessarily mean someone has poor hygiene.

The chemistry behind changing body scent

One compound has received considerable attention in research into age related scent: 2 nonenal.

The molecule can develop when certain fats on the surface of the skin undergo oxidation. As skin chemistry changes with age, those reactions may become more likely, potentially contributing to a noticeable shift in body scent.

But researchers caution against treating 2-nonenal as the entire explanation.

Studies suggest levels of the compound may begin changing around middle age, but they do not necessarily continue increasing throughout a person’s life. Individual differences can also be significant.

Research from the Monell Chemical Senses Center further complicates the picture. In one study, participants evaluated underarm odor samples from people in different age groups. The findings suggested that odors from middle aged participants were rated less favorably than those from older participants.

The results indicate that age related scent cannot simply be explained by getting older. Instead, several biological and environmental influences may work together.

Lifestyle can make a difference

A person’s daily routine can also influence natural scent.

Certain medications and supplements may change sweat or body odor. Diet can have an effect as well, with foods such as garlic, onions, alcohol and some spices known to influence scent in certain people.

Clothing and laundry habits can also contribute. Fabrics can retain odors, while changes in how often clothing is washed or replaced may affect the way someone smells.

Skin care matters, too. As skin changes with age, maintaining a healthy skin barrier and keeping the skin clean and moisturized can help manage natural body scent.

These factors mean that age itself is only one part of a much broader picture.

Memory can shape what we think we smell

There is another fascinating element to the science of scent: perception.

Smell is closely connected with memory and personal experiences. A particular fragrance can remind someone of a grandparent’s home, older furniture, certain soaps or familiar household surroundings.

Those associations can influence how a person interprets a scent before they consciously identify its source.

That means the perception of an age-related smell may involve both chemistry and expectation. Two people could encounter the same scent and interpret it differently based on their experiences and memories.

When a change in scent deserves attention

Gradual changes in natural body scent are generally not something to worry about. However, a sudden or significant shift can sometimes be worth discussing with a health care professional.

A new scent accompanied by unexplained weight changes, fever, unusual sweating, changes in urination or other new symptoms may warrant an evaluation.

Rather than automatically attributing a sudden change to age, a doctor can determine whether a medication, health issue or another factor may be contributing.

Simple ways to manage body scent

There is no universally established treatment designed specifically to eliminate 2 nonenal. Still, everyday habits can help keep natural body scent under control.

Gentle cleansing, regularly washing clothes and moisturizing the skin can support overall skin health. Staying hydrated, maintaining a balanced diet and managing ongoing health concerns may also help.

Foods containing antioxidants, including berries, leafy greens and beans, have been suggested as another possible avenue, although more research is needed to determine whether they meaningfully reduce age associated scent compounds.

Ultimately, getting older does not automatically mean developing one specific smell. Body scent reflects a complicated mix of skin chemistry, sweat, the skin microbiome, lifestyle, environment and perception.