First person · Aging well

Over 60? The real reason for “grandma smell” has nothing to do with hygiene

You can't smell it on yourself, and nobody will tell you. Japanese researchers found the cause in 2001, and women in Japan wash it away with a fruit.

A news anchor in a studio in front of a screen showing a street interview with an elderly Japanese woman holding a bar of persimmon soap — Tap to watch (1:16, sound on). A street interview in Japan, where the smell of aging has its own name, and a fruit that women wash with. (Photo illustration)

By Carol Whitaker, 64 · Reader story · Advertorial
Published October 3, 2026

What to know

“Grandma smell” comes from 2-nonenal, an oily compound skin starts making after 40. Japanese researchers identified it in 2001.¹
You can't smell it on yourself, and ordinary soap, made for sweat and dirt, slides right past it.
Women in Japan wash with fermented persimmon tannin. See the persimmon soap Carol uses.

Last Christmas my granddaughter Lily climbed onto my lap, pressed her face into my sweater, and said something I will never forget.

“Grandma, you smell like Great-Grandma's house.”
My granddaughter Lily, age 6

Everyone laughed. I laughed too.

Then I went to the bathroom, held my cardigan to my nose for a full minute, and smelled... nothing at all.

That scared me more than anything.

A child's drawing on the fridge that says My grandma smells like — Lily's school worksheet, still on my fridge. I covered the last word with a magnet. (Photo illustration)

If you're over 60, you probably know that feeling. Here's what I found out.

It isn't sweat. It isn't dirt. It has a name.

In 2001, researchers in Japan found an oily compound on the skin of people over 40 that wasn't there in younger people. It's called 2-nonenal.¹ Our own skin makes it as we age, and it builds up year after year.

In Japan it even has its own word: kareishu, the smell of aging. It has nothing to do with being clean, and it is nobody's fault.

Fast facts: 2-nonenal

An oily compound the skin makes as we age
Found on people over 40, not in younger people¹
Builds up year after year and settles into fabric
In Japan the smell has a name: kareishu

Why more showers never fixed it

2-nonenal is oily. Ordinary soap is made for sweat and dirt, so it slides right past it. Think of a greasy frying pan under the kitchen tap: the water runs off, the grease stays.

Water running off a greasy frying pan while the grease stays — Water and ordinary soap slide off an oily film. That's why the smell keeps coming back. (Photo illustration)

What women in Japan use instead

They wash with green, unripe persimmons, the kind that make your mouth pucker. That pucker is tannin. Fermented, it's called kakishibu, and it's one of the best-known answers to kareishu in Japan.

Here in the U.S., the one I use is called SAWUMI: a gentle bar with real fermented persimmon tannin pressed into it. Thirty seconds a day in the shower: neck, behind the ears, chest, back. Rinse.

And you don't have to take my word for it. They give you 60 days. If your pillowcase doesn't notice a difference, one email gets every penny back, and you don't send anything back.

See the Japanese persimmon soap I use (and check if it's in stock)

The SAWUMI persimmon soap bar next to a fresh persimmon — SAWUMI: real fermented persimmon tannin in a gentle bar. (SAWUMI)

Check availability →60-day money-back guarantee

That's the short version. If you want the whole story, including why you can't smell it on yourself and everything I tried first, here it is.

Why you can't smell it on yourself

Your nose is built to tune out smells that are always there. It's the same reason you stop hearing your refrigerator hum.

So the woman with the grandma smell is always the very last to know. And the people who love her are far too kind to say a word.

I asked my sister once: “Please, just tell me. Do I have that smell?” She said, “Of course not.” She couldn't even look at me.

A woman in her sixties checking the smell of her own sleeve in a hallway mirror — How many times a day do you do this? (Photo illustration)

A smiling Japanese grandmother holding half a persimmon in her kitchen — In Japan, the smell of aging is talked about openly. And handled. (Photo illustration)

Do you have it? The 10-second self-check

Tap the ones that sound like you

You've caught yourself smelling your pillowcase, sweater or cardigan.
Clothes smell “stale” after one wear, even fresh from the wash.
A room you sit in a lot smells different when you come back to it.
You shower every day and still quietly worry.
You're over 40.

If you checked two or more, you're not imagining it. Keep reading, because this next part is what finally made sense of it for me.

Carol's pickThe fermented persimmon soap I use every dayCheck availability →

Why it gets stronger after 60

Here's what the Japanese researchers found. As we get older, our skin makes more of a certain kind of natural oil. When that oil meets the air, it slowly breaks down, and one of the things it turns into is 2-nonenal.¹

That's why it creeps up so quietly. It isn't something you did. It's the same chemistry that happens to every one of us, and it builds a little more each year.

And because it's oily, it doesn't stay on your skin. It rubs off into everything you touch: your pillowcase, your favorite chair, the collar of your coat, the seat of your car. That's why it becomes the smell of a whole house, not just a person.

A lavender cardigan with a tag that says washed 3 times, still smells like Grandma — It settles into the fabric you wear most. (Photo illustration)

Everything I tried first, and why each one failed

Stronger soap. Made for sweat and dirt. It slides past an oily film.
Fancy scented body wash. Adds a scent on top. Underneath, nothing changes.
Deodorant everywhere. Made for underarm sweat, not the oil on your neck and back.
Longer, hotter showers. More water, same soap, same result.
Washing sheets on hot with bleach. Clean for one night. Then it comes back from your skin.
Perfume on my cardigans. Covered it for an hour. Then the two smells mixed.

A drawer full of soaps, sprays and deodorants with a note that says none of these worked — My bathroom drawer. Hundreds of dollars, and none of it was made for this. (Photo illustration)

None of it was wrong. It just wasn't made for this. Every one of those products was built for sweat, dirt or covering things up. Not for an oily compound your own skin makes.

Why persimmon tannin is different

Tannin is what gives a green persimmon its grip. In SAWUMI, that tannin goes to work in the lather: the company explains that it binds to the nonenal on your skin so it rinses away with the water, instead of being covered up.

That's also why it has to be real fermented tannin. Some soaps online look the same and smell like persimmon, but have almost none of it inside. A fruit smell does nothing for kareishu.

Green unripe persimmons on a branch in a Japanese garden — Green, unripe persimmons. The pucker is the tannin. (Photo illustration)

Unripe persimmons and a wooden vat of fermenting persimmon juice in Japan — Kakishibu, fermented persimmon tannin, has been made in Japan for centuries. (Photo illustration)

Here's the real one, made with fermented kakishibu

What happened when I tried it

Day 1. It lathered like a good, creamy bar. The scent was soft and natural and rinsed off completely. My skin didn't feel tight afterwards, which matters at my age.

Day 3. I noticed my bath towel smelled like a bath towel. Just clean.

Day 5. I did my pillowcase check. I held it to my face like I always do, and for the first time in a long time, that tight feeling in my chest wasn't there. It smelled like clean cotton.

A woman in her sixties fluffing a fresh white pillow on a made bed — The pillowcase check. It takes ten seconds. (Photo illustration)

Week 3. Lily came for the weekend. She fell asleep on my shoulder during a movie, and when she woke up she just said, “You smell nice, Grandma.”

I didn't say anything. I just held her a little longer.

A grandmother hugging her granddaughter close on the sofa — No more pulling back from hugs. (Photo illustration)

Check availability →Try it for 60 days. Every penny back if your pillowcase doesn't notice.

How to do the pillowcase check yourself

Ten seconds, once a week

Put a freshly washed pillowcase on tonight.
Use SAWUMI once a day in the shower: neck, behind the ears, chest, back.
After a week, hold the pillowcase to your face before you change it.
Then do the same with the collar of the cardigan you wear most.

Your pillowcase spends eight hours a night against your neck and hair. It notices what you can't. If it doesn't notice a difference within 60 days, you get your money back.

Questions I had before I tried it

Is this only for very old women?

No. 2-nonenal starts building after 40. Most women I've told about it are in their 50s, 60s and 70s.

Will it make me smell like fruit?

No. The scent is soft and natural, and it rinses off completely. After my shower I smell like nothing. Just clean.

My skin is dry and thin now. Is it harsh?

Not for me. It's made with olive oil, coconut oil, shea and glycerin, and it's sulphate free. It feels like a good, honest bar of soap.

Do I have to change my routine?

No. You use it instead of your regular soap. Neck, behind the ears, chest and back, about thirty seconds.

What if it doesn't work for me?

You have 60 days. If you, or your pillowcase, don't notice a difference, one email to help@sawumi.com gets every penny back. Nothing to send back.

A woman lathering an orange persimmon soap bar on her neck — Thirty seconds: neck, behind the ears, chest and back. (Photo illustration)

What I like, and the one thing I don't

It goes after the cause, not just the smell on top.
Real fermented persimmon tannin, not a fruit scent.
Thirty seconds, in the shower I already take.
Gentle on dry, thin skin.
60 days to try it, and my money back if not.
It's a bar, not a body wash. It took me a day to get used to a bar again.

Two women in their sixties laughing in a close hug in a kitchen — I don't think twice about a hug anymore. (Photo illustration)

I wish my mother had known

My grandmother had that smell, and I loved her for it. It meant her. My mother worried about it in silence for twenty years.

We know more now. We know what causes it, we know it's not our fault, and we know what women in Japan have used for generations.

Is it a miracle? No. It's a bar of soap with something in it that ordinary soap doesn't have. I can't promise it works the same for everyone; nobody can. What I can tell you is this: one bar, thirty seconds a day, and you check your pillowcase in a week. You have 60 days to decide.

Try the pillowcase check yourself

Check availability →60-day money-back guarantee

¹ Haze S, Gozu Y, Nakamura S, et al. 2-Nonenal newly found in human body odor tends to increase with aging. Journal of Investigative Dermatology. 2001;116(4):520-524.

This is a dramatized story based on what SAWUMI customers have told the company; names and photos are illustrative. Individual results vary. SAWUMI is a cosmetic soap and is not intended to diagnose, treat, cure or prevent any disease.

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