Short answer: "Old person smell" is a mild, slightly greasy, stale scent that can develop with age. Part of it probably comes from nonenal, a compound released when skin oil reacts with oxygen. Clothes, bedding, furniture and a poorly aired home then hold on to it. Daily washing, frequent changes of clothes and bedding, and fresh air every day make the biggest difference.
It is a delicate subject. You may have noticed it when visiting a parent or grandparent, or you may be quietly wondering about yourself. The first thing to know is that it is normal. It is not an illness, and it does not mean someone has stopped looking after themselves. There are a few clear causes, which means there are also sensible things you can do.
What "old person smell" actually is
Everyone has a personal scent, and it changes over a lifetime. Researchers at the Monell Chemical Senses Center in the United States asked 41 young volunteers to rate body odour samples from three age groups. The volunteers could correctly identify only the oldest group, people aged 75 to 95. Yet that group's odour was rated less intense and less unpleasant than the samples from younger and middle-aged donors (Mitro et al., 2012, PLoS One).
In other words, the smell of older age is recognisable, but not necessarily strong or unpleasant. What people notice in real life is often a mix of body odour and smells that have built up in fabrics and rooms over time.
Cause 1: nonenal from skin oil
Skin produces a thin film of oil every day. In 2001, researchers at the Japanese cosmetics company Shiseido reported that certain fatty acids in that film, and fats that had already reacted with oxygen, increased with age. When those fatty acids break down, they release 2-nonenal, which has a greasy, grassy smell. The team found it only in participants aged 40 and over (Haze et al., 2001, Journal of Investigative Dermatology).
A later Japanese study found that the skin at the back of the neck gives off more 2-nonenal with age, in both women and men (Kimura et al., 2016, Journal of Chromatography B). However, a US study did not detect 2-nonenal at all, and found other compounds higher in older adults instead (Gallagher et al., 2008, British Journal of Dermatology). So nonenal is likely to be one part of the picture rather than the whole of it. There is more detail in what is nonenal?
Cause 2: sweat and skin bacteria
Body odour in general is produced by bacteria on the skin breaking down sweat, as nidirect, the Northern Ireland government's information site, explains. That is true at any age.
Some things can make it more noticeable. The NHS lists hot weather, being overweight, hormonal changes, conditions such as diabetes, kidney disease and liver disease, and certain medicines, such as antidepressants, among the factors that can make body odour worse. Practical difficulties count too. If getting in and out of the bath has become hard or worrying, people often wash less thoroughly, and the smell returns more quickly.
Cause 3: clothes, bedding and furniture
Skin oil does not stay on the skin. In one Japanese study, researchers measured nonenal in cotton T-shirts that men had slept in for three nights (Tatsuguchi et al., 2012, Journal of Japan Association on Odor Environment). Think about the fabrics that touch skin for hours and are washed less often than they might be:
- pillowcases and sheets;
- cardigans, jumpers and shirt collars worn several times between washes;
- the favourite armchair or sofa, especially the headrest and arms;
- coats, scarves and hats, which rarely go in the machine.
Cause 4: the home itself
Rooms with windows kept shut and plenty of soft furnishings, such as curtains, rugs and cushions, hold on to smells for longer. The person who lives there usually stops noticing, because the nose quickly gets used to familiar smells. A visitor notices straight away.
Causes at a glance
| Cause | Where you notice it | What helps |
|---|---|---|
| Nonenal from skin oil | Back of the neck, behind the ears, upper back, pillowcases | Daily washing with soap, with extra care in those areas |
| Sweat and bacteria | Armpits, groin, feet | Washing, drying thoroughly, deodorant or antiperspirant |
| Fabrics | Clothes, bedding, chairs | Frequent changes, warmer washes where the label allows |
| The home | Bedroom, sitting room, wardrobes | Fresh air every day, clearing out wardrobes now and then |
What helps
There is no miracle product, but a steady routine goes a long way:
- Wash every day with soap and water. Soap helps wash away the oily residue that carries the smell.
- Pay attention to the back of the neck, behind the ears, the chest and the upper back. These areas are oily and easy to miss in a quick wash.
- Wash armpits, groin and feet thoroughly and dry them well. The NHS suggests doing this at least twice a day.
- Choose natural fabrics such as cotton, wool and silk, and change clothes often.
- Change pillowcases more often than the rest of the bed. Twice a week is a good habit.
- Open the windows every day, even in winter, if only for ten minutes.
- Don't rely on masking. Perfume and air freshener cover a smell for a while but leave the cause in place.
For washing temperatures, oxygen bleach and soft furnishings, see how to get the smell out of clothes and the home. Some people choose a soap made with persimmon extract; does persimmon soap work? sets out what is and isn't known, and our comparison page gives a neutral overview of the options.
How to raise it with a parent
Starting the conversation is often the hardest part. A few things tend to help:
- Choose a quiet moment, in private.
- Talk about the laundry or the house rather than the person: "Shall I give you a hand washing the cushions and cardigans?"
- Offer practical help, such as a shower stool, a grab rail or help with heavy washing.
- Stay kind. This smell says nothing about how well someone looks after themselves.
When to see a GP
See a GP if body odour changes noticeably from how it usually smells, or if someone suddenly starts sweating much more than usual; the NHS lists both as reasons to get advice. It is also worth booking an appointment if other symptoms appear alongside the change, because it can have causes other than getting older. In the US, speak to your doctor.
Frequently asked questions
Is old person smell a sign of poor hygiene?
No. People who wash every day can still have it. Washing does help keep it to a minimum.
At what age can it start?
In the 2001 Japanese study, nonenal was found only from the age of 40. That does not mean everyone notices a change then; it varies widely.
Why don't older people notice their own smell?
Because the nose gets used to smells that are always around. That is true for everyone, at any age, and it applies to the smell of our own homes too.
Does deodorant help?
Deodorant and antiperspirant mainly help with underarm odour. The smell linked to skin oil comes from the neck, back and behind the ears as well, where washing with soap does more.