Why Do Older Adults Have a Distinct Smell? Exploring the Reasons Behind It

A change in body odor with age is linked to a compound called 2-nonenal, skin changes, and medicines or difficulties with hygiene.

2-nonenal

Japanese researchers (Haze et al., 2001) found 2-nonenal, a compound that increases with age and gives a greasy, grassy odor. It’s produced by the breakdown of fatty acids on skin.

Other factors

• Skin changes.
• Medicines and medical conditions (diabetes, kidney disease).
• Incontinence.
• Poor hygiene due to mobility problems or dementia.
• Dry mouth and dental problems.

Respect

Body odor changes with age are normal and can be handled kindly.

What helps

Regular washing with gentle soap, clean clothes and bedding, treating health issues.

Caregivers

Offer help with bathing.

See a doctor

If the odor changes suddenly.

2-nonenal

Research from Shiseido scientists in Japan, published in 2001, identified 2-nonenal, an unsaturated aldehyde with a greasy, grassy smell, in the body odor of people over 40. It forms when omega-7 unsaturated fatty acids in skin oils break down through oxidation. Skin antioxidant levels fall with age, and oil composition changes, leading to more oxidation. Later studies found that the presence of 2-nonenal may not fully explain “old person smell,” and other compounds also change with age.

Other factors

• Slower skin renewal, and skin dryness, which hold odors.
• Medications and health conditions: diabetes, kidney disease, liver disease and infections can change smell.
• Dental problems, dry mouth and dentures that are not cleaned.
• Urinary incontinence, which is common with age.
• Reduced mobility or vision, making bathing and laundry harder.
• Dementia or depression, which can reduce self-care.
• Smoking and strong foods.
• Decline in sense of smell, so people may not notice odors on themselves. Smell loss affects about half of those aged 65 to 80 and over 80% of those over 80.

Respect

Not every older person has a noticeable smell. Many older adults smell no different from younger ones. Body odor varies by hygiene, health, environment and genes. Be tactful when bringing up the topic.

What helps

• Regular bathing with gentle soap, and washing skin folds.
• Fresh, clean clothes daily and regular bedding changes. Wash with hot water and add vinegar or baking soda to remove odors.
• Moisturize dry skin.
• Daily oral care, denture cleaning and dental checkups.
• Prompt treatment for incontinence and UTIs.
• Air out the home, and clean carpets and furniture.

Caregivers

Offer help in a kind, private way. Create a bathing routine, install a shower chair and grab bars, and use no-rinse cleansers when showers are hard. Ask the doctor to review medications.

See a doctor

A sudden change in body odor, such as a fruity, ammonia or foul smell, can point to diabetes, kidney failure, liver problems or infection and should be evaluated by a doctor.

Perceptions and aging skin

Odor changes with age are real but often smaller than people assume. A 2012 study in Chemical Senses by the Monell Chemical Senses Center found that young and middle aged volunteers rated the smell of people aged 75 to 95 as less intense and less unpleasant than the smell from middle aged people. The compound 2-nonenal was proposed in Japanese research as an age related scent, but studies since have not consistently confirmed it as the main cause. Skin dryness, reduced sense of smell in older adults, incontinence, smoking, medication side effects and certain illnesses can add to smell. Bathing too often can also dry skin. Regular laundering of clothing, a clean living space, oral care, treating skin infections and check ups help. Sudden odor shifts can signal diabetes, kidney failure or infection and should be checked by a doctor.

Based on data from the Monell Chemical Senses Center and the National Institute on Aging