For months now, somebody has asked us the same question — most days, several times a day. In the DMs. In the comments. In the customer service inbox.

"Do you make a persimmon soap?"

That's the polite version. More often, it's "you NEED to make a persimmon soap," sometimes with a link, sometimes with a screenshot of a bar we don't sell.

So months ago, I did what I've done for thirteen years whenever someone tells me there's a better soap than ours: I went looking. Because if persimmon soap really was better, the answer was obvious — we should make one. I read the research. I read the ingredient lists. I read the claims on the boxes, and then I went hunting for the studies behind the claims.

I came out the other side of that rabbit hole with a decision: no. We won't be making one.

And then we did what small businesses do with decisions like that. We made an ad about it.

Thirty-odd words. And last week, those thirty words made a lot of you very angry.

About That Ad

Can I say something about ads first?

When you're the founder of a small soap company, you have to put your shame to one side and get in front of the camera. I didn't start this business to appear, uninvited and repeatedly, in your feed. Believe me, I'm sorry about that part. But it's how a small Melbourne soap company survives in 2026, so there I am, wedged between your niece's baby photos and someone's air fryer.

Here's the thing about an ad, though. An ad is a conclusion with the workings torn off. Months of reading, compressed into a sentence. And when we compressed "the smell persimmon soap targets is real, but the evidence for the soap is thinner than the marketing," what a lot of you heard was "the smell isn't real."

That's on me.

Several of you told me to look up 2-nonenal. Some of you named the study. One of you said we'd lost her as a customer. And a few of you sent me research, which I've now read too.

So here are the workings. All of them.

The Smell Is Real. You Were Right.

It has a name — 2-nonenal —, and it has been solid science since 2001, when researchers writing in the Journal of Investigative Dermatology identified it in human body odour and showed it increases with age (Haze et al., 2001).

What happens is this. From around 40, the mix of your skin's natural surface oils changes. A fatty acid called palmitoleic acid increases, the skin's antioxidant defences ease off, and when that oil oxidises on the surface of the skin, it produces 2-nonenal — an aldehyde with a slightly greasy, grassy smell. It's oily, and it doesn't dissolve in water. That's why a quick rinse doesn't shift it, and why it can linger in fabric and bedding. Later lab work found it can even bond chemically to proteins (Ishino et al., 2010). It is a stubborn little molecule.

None of this is anyone's fault. It isn't poor hygiene. It happens, to some degree, to virtually everyone lucky enough to keep having birthdays.

If our ad read to you as denying any of that — I'm sorry. It's real, it has a molecule, and the researchers who found it did careful work.

So Does Persimmon Soap Actually Fix It?

Now, the part I went looking for months ago, and looked at again this week.

First, the honest kernel: persimmon tannin is real chemistry. Tannins are large plant polyphenols, and in laboratory studies, they can bind reactive aldehydes like nonenal. That's the truth inside: "it removes the smell rather than covering it up", and I won't pretend otherwise. One commenter suggested a green tea spray — same family of chemistry, and the lab work on green tea catechins is real too.

Then I went hunting for the human evidence, because a test tube is not a shower.

In the major medical databases, a search for persimmon and body odour turns up papers on test tubes, textiles, ammonia gas and animal feed. Not one published trial of a persimmon bar on human skin.

The strongest thing I found came from one of you. A reader sent me a study I hadn't seen: a small Japanese trial from 2012, in which twenty men aged 43 to 75 washed for four weeks with a soap containing a polyphenol blend drawn from oolong tea, green tea, tiencha and astringent persimmon — and the nonenal on their skin reportedly decreased (Tatsuguchi et al., 2012). That's a real result. I won't wave it away. It is the strongest card in the persimmon deck.

But look at it the way you'd want any claim about your health looked at. One study. Twenty people. A tea-and-persimmon blend, not the persimmon bars actually on the market. Published in a specialist odour-research journal that the major medical indexes don't cover. In science terms, that's a promising start — not settled proof.

And there's a question hanging over every rinse-off product: a bar of soap is on your skin for maybe twenty seconds before it washes away. How much tannin stays behind to keep working? On the published evidence, nobody knows.

What's Actually In These Bars?

This was the part of the rabbit hole that surprised me most.

I pulled the ingredient list of the biggest persimmon brand's flagship body wash. Have a guess what the first two working ingredients are.

Sodium C14-16 olefin sulfonate. Cocamidopropyl hydroxysultaine.

Synthetic detergents. The same family of surfactants used in the commercial body washes we've spent thirteen years talking about — with persimmon extract added, alongside synthetic preservatives and thickeners. The bar versions from the same brand list their base simply as "soap material." Which oils? Not disclosed.

The claim on the box says the bar eliminates nonenal "97%, compared to 35% for regular soap." So I went looking for the trial behind that number. Who ran it? Who reviewed it? Where was it published? I can only read what's published — and I could not find a study anywhere that produces that number.

I've looked long and hard at these labels, and I'll say plainly what I concluded months ago: I cannot understand how they're better than the soap we already make. When a product's entire pitch is what's in it, you're entitled to know what's in it.

Australian Natural Soap Company team hand-pouring golden olive oil soap mixture during the handmade soap-making process in Melbourne, Australia."

The Part Nobody's Ad Account Will Say Plainly

The smell lives in your skin's own oils. So looking after it mostly comes down to lifting those oils away — gently, thoroughly, regularly. That is not a hero ingredient. That is soap, doing what soap has done for a few thousand years. It's also the same cleansing action a persimmon bar relies on for most of its work.

And no soap — ours, theirs, anyone's — is once-and-done. Your skin keeps making those oils, so the smell reforms. The job is daily and whole-body: chest, back, behind the ears, the places a quick shower misses. Which makes the real question very simple: can your skin happily tolerate your soap every single day, everywhere?

That's the job we built ours for.

• Cold-pressed from more than 80% pure plant oils — predominantly Australian-grown.
• Palm oil-free.
• Cured for four to six weeks — the slow way, which keeps the naturally occurring glycerin in the bar instead of stripping it out.
• No synthetic detergents. No sulphates.
• Scented with pure essential oils, or not scented at all.
• Home compostable packaging.

Gentle enough for every day, all over — which, for this particular job, is the entire point.

If Persimmon Soap Works For You — Wonderful

Truly. Skin is personal, and nobody knows yours better than you do. If a persimmon bar has earned its spot on your shower shelf, keep it there with our blessing. Our quarrel was never with persimmon, and it certainly wasn't with you.

What We Still Won't Do

We won't call it "old people's smell."

Because that phrase isn't science. It's marketing. The chemistry above is a normal part of skin ageing, in the same category as needing reading glasses, and "old people's smell" takes something universal and turns it into something to be ashamed of. Shame is very good at selling things.

I know a bit about putting shame to one side. I do it every time I film one of those ads. What I won't do is turn around and sell shame back to you — about skin that is simply getting older, and doing what everyone's skin does.

You were right about the molecule. We could have said it better. This is us saying it better.

Real soap. Real respect.

References: 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, 116(4), 2001. — Ishino K., et al. "Lipid Peroxidation Generates Body Odor Component trans-2-Nonenal Covalently Bound to Protein in Vivo." Journal of Biological Chemistry, 285(20), 2010. — Tatsuguchi I., et al. "Preventive effect against the aged men's body odor by the soap containing polyphenol." Journal of Japan Association on Odor Environment, 43(5), 2012.