Dr. Norman Swan (2:16)

And today it's why do we wash our hair? And the question comes from Steve.

Norman Swan (2:20)

Steve says, I was talking with my partner and we got onto the subject of shampoo. I was wondering about the scientific side of using shampoo and conditioner on hair. How should a person use it effectively? Does it matter if you have oily, normal or dry hair? How often should we shampoo and condition our hair. What a fun rabbit hole this has been to go down.

Dr. Norman Swan (2:39)

And it just plays to your strength here. So tell us all about the history of shampoo, or as some would say, champoo shampoo.

Norman Swan (2:46)

Exactly. So it seems that cleansing of the body and cleansing of the hair is something that has been part of cultures around the world for quite a long time. The Mesopotamians did it, et cetera.

Dr. Norman Swan (2:58)

But she and may well have spread to the west from the eas.

Norman Swan (3:02)

This is it. So shampoo. Shampoo, as you said, probably came to Europe or the UK via India. And the word comes from Sanskrit. So an early shampoo was boiling soap berries, which was called sapindis. And then when colonisers, colonial traders got to India, they noticed this practice and it was called shampoo because shampoo comes from the word for like, massage. And then it sort of became like the way you would massage your scalp to clean your hair. And they brought it back to Europe and they called it shampoo because it was a bastardization of the word shampoo. And then that is really where this origin of this, not just the word, but also the practice came from.

Dr. Norman Swan (3:44)

And they reckon the origin of the word in Sanskrit goes right back to chapati, which is well known to be the. You know, the.

Norman Swan (3:50)

The bread.

Dr. Norman Swan (3:51)

The bread that you get because it means to press, to knead and soothe, and then chapati, chapo champu in Hindi. And so that's one of the linguistic derivations that sought to exist.

Norman Swan (4:02)

I mean, all of our language comes from proto Indo European, which really, its seat was India. So that makes perfect sense that we would keep borrowing words from Indian languages. Also, in researching this, I found a whole book. It's called A History of Personal Hygiene and Purity, which kind of touches on stuff we've spoken about before. You and I now have quite a long and storied history of talking about cleanliness. On whatsat rash, we talked about skipping your shower in January. We talked about conventional versus natural deodorants in March. And really it's the same tradition of whether or not we're being sold a big scam or whether or not we are simply being kind to the nostrils of those around us. And I feel like this question about shampoo and conditioner really kind of plays into the same place.

Dr. Norman Swan (4:51)

Partly, yes. And one of our colleagues who used to present the Drive show on ABC Radio, Sydney, Richard Glover, he's not washed his hair for months.

Norman Swan (5:01)

Ah, A no pooer. There's this thing called the no poo movement, which has nothing to do with dietary fibre and everything to do with the last syllable of the word shampoo, where people opt out of using commercial shampoos or even any kind of, like, soap on the head at all.

Dr. Norman Swan (5:19)

Yeah. And, you know, theoretically, there's lots of reasons why people would say that. One is they believe that the chemicals in shampoo are potentially toxic. Another is that you are affect the microbiome of the scalp, which is probably true. There's a microbiome on the scalp which is specific to the hair follicles as well as the skin, and that could be affecting the health of the scalp and risk to the environment because of rinse off plastics. And in fact, in some states in Australia, they have banned shampoos which have plastics in them for scrubs and what have you. Because you're rinsing off microplastics into the environment.

Norman Swan (5:55)

Exactly. So there's lots of different reasons why people might opt out, but I think I don't have hard data to back this up. I am guessing that the majority of Australians probably do use a commercial shampoo and conditioner in the shower, at least, I don't know, once a week or so. So maybe we should talk about what is actually in these products and what they're trying to do to our hair.

Dr. Norman Swan (6:15)

So there's detergents which break down surface tension in water. They get into grease and allow it to be soluble in water and remove skin scales, fat from the hair and scalp. Then there are foam agents which allow the shampoo to form suds. And this is partly a marketing thing. It's got nothing to do with cleaning your hair. It's to convince you that you're actually using shampoo on your hair. And then the conditioners which leave the hair soft and smooth to replace the fat that's been removed by the detergent. There's thickeners to thicken the shampoo, opacifiers to make the shampoo opaque as opposed to translucent, because, again, people think that that's more like a real shampoo. And there are other agents, like sequestering agents to prevent soap scum from forming on the hair and scalp. When you've got hard water fragrances to give it a nice smell, preservatives to stop microbial and fungal contamination of the shampoo before and after opening, which is where you get parabens in shampoo. And if you read on the label, many shampoos now say 0% parabens. And then you've got all the additives, you know, blueberry, BlackBerry, God knows what else they Stick in shampoos. It's about the shampoo feeling luxurious and making your scalp feel better. And then the conditioner is actually to fix up some of the problems created by the shampoo.

Norman Swan (7:37)

I want to roll my eyes and be like, oh, like idiots who are buying this stuff. Like, I'm too smart. But I love a good. Love a good shampoo. I love a good sudsy foam. I love it when they're a little bit, like, sometimes they've got, like, a little bit of, like, a pearlescent quality to them. It does feel a part of the experience, especially if you are like, it's hard to spend less than 15, 20 bucks on a shampoo, even just the ones at the supermarket. If you're spending good money on it, you sort of want it to feel like a little bit of a spa experience.

Dr. Norman Swan (8:07)

But some of the consumer organizations have done studies of these shampoos, and the cheaper ones are as good as the ones that are more expensive. I mean, you've got all these fancy things in them. They're not necessarily doing your hair any good. Then there's a whole technology around conditioners.

Norman Swan (8:21)

Conditioners are actually way more chemically interesting than I expected them to be.

Dr. Norman Swan (8:25)

Yeah, they give a positive charge. So there's a positive charge to counteract the negative charge of the hair. And the positive charge of the conditioner attracts the hair to the conditioner particles. And so the conditioner gets deposited on the hair, particularly in parts of the hair that's exposed to the sun and the weather. And apparently damaged hair attracts the conditioner more than intact hair. So you reduce the static electricity that you might get in your hair. It seems to smooth out the cuticles at the bottom of the ha hair shaft, which gives you that smooth feeling for both the hair and the scalp, making combing and brushing much easier.

Norman Swan (9:08)

So we do the washing with the shampoo. It introduces a bunch of problems that we then treat with a conditioner because we've taken the oil out of the hair. I suppose the question is, do we need to wash our hair? We can get into the no poo movement and all of the motivators for that in a second. But if this is something that our ancestors have been doing across cultures for hundreds, if not thousands of years. We wash our bodies, we cleanse ourselves. We do get dirt and grime and stuff build up on our surfaces. Why wouldn't we wash it?

Dr. Norman Swan (9:39)

Well, that's my view, but I think that you want to be careful about how chemically oriented you go, because some of this stuff you put on your hair will be absorbed, and we don't know the effect of that.

Norman Swan (9:51)

So what I'm hearing you saying is that, yes, there's chemicals in these shampoos and conditioners. Maybe we're trading with caution here. So let's talk about what the concerns that have kind of motivated this no poo movement and whether there is actually anything to it or how much weight to put on it.

Dr. Norman Swan (10:05)

I guess, like a lot of these things in terms of toxins in the environment, there's just not been enough research to know truly what the risks are. And therefore, a lot of people go into risk avoidance, which is really the precautionary principle that you and I talked about all the time on Corona cats, which is, if you don't know the risk of something and there's no harm in removing it, well, why not remove it? And that's part of what drives the no poo movement of not washing your hair. But equally, you know, there's a whole social aspect to this as well.

Norman Swan (10:35)

So when we did our showering episode, Norman, we heard stories of people who had given up using, like, commercial body washes or whatever, or just didn't shower anymore, and that they'd sort of talk about going through, like, a stinky phase and then getting to sort of like their body sort of like shedding or recalibrating or something like that. Similarly with the natural deodorants or not wearing deodorants at all, that you sort of go through a phase where your body stinks because it's getting used to not having those chemicals on them. And when I'm looking at people talking about the no shampoo movement, it's the same kind of story again. Like, I quit shampoo, and this is what happened next. And the first week or so, their hair's greasy and oily, and then it gets better and their body gets back into equilibrium again. Is this true?

Dr. Norman Swan (11:20)

Yeah, I think that's right. I think that's what people talk about anecdotally.

Norman Swan (11:23)

What would be happening here?

Dr. Norman Swan (11:25)

Well, a feedback mechanism, I'm speculating now, is a feedback mechanism to the sebum production from the hair follicles. So the hair follicles produce fat called sebum, and you are shampooing, and therefore you are rinsing away the sebum. And quite possibly what you're doing by that process is actually increasing the production of sebum from your hair follicles, which continues after you've stopped shampooing, which makes your hair greasy. But then the Feedback loop settles it back down to a normal production of Sebum. Therefore, it settles down.

Norman Swan (11:58)

So, Norman, I guess we love an N equals one study here on what's that rash where we've got just one person. Anyway, Shelby has sent me a highly scientific Instagram video.

Dr. Norman Swan (12:07)

Oh, yeah, totally reliable.

Norman Swan (12:09)

Shelby Trainer, our producer, sent me this Instagram video of a woman who's going, this is what healthy hair looks like. One year, no poo. And she's just sort of like tussling her hair and she's got long hair. Because this is the other thing that I have noticed a lot with this trend with no shampoo is it's often blokes who are like, I don't shampoo my hair anymore. And I'm like, congratulations, your haircut is three inches long. Like, well done. I guess this is me saying it. I also have quite short hair, but when I've had long hair, you really want to trust that you're going to be able to put a brush through that thing. Like, you can't risk not being able to take care of your hair. Anyway, this woman has what I would call mermaid length hair and it looks very healthy and not very oily at all. So maybe, maybe they're all right. Maybe this is fine. No shampoo for life.

Dr. Norman Swan (12:55)

Did Rapunzel use shampoo?

Norman Swan (12:56)

That is an excellent question. I've never asked her personally, but maybe.

Dr. Norman Swan (13:00)

Having handsome knights climbing it up, climbing.

Norman Swan (13:02)

Up there, you know what it takes. You might fall down. This is highly scientific. We need to give Steve, poor Steve, who's asked this question, we need to give him something to actually go on that's scientifically based here. Is there any health benefit from washing your hair or is there any health benefit from not washing your hair? Please, Based in science.

Dr. Norman Swan (13:23)

Based on science. We don't know.

Norman Swan (13:26)

It is hard in a space which is so commercialised and it's very, very hard to find, even just kind of like top line information that isn't sponsored by like Pantene or Herbal Essences.

Dr. Norman Swan (13:36)

Well, that's right. And some people wash their hair once a week. And I personally wash my hair every.

Norman Swan (13:41)

Day with shampoo and conditioner.

Dr. Norman Swan (13:42)

Oh, no, I never use conditioner. What Shelby said. It's a shame the audience can't hear Shelby in her ears saying, men. Yeah, no, I just have a quick smear with paraben free cheap shampoo and rinse it out.

Norman Swan (13:57)

Are you one of those blokes that uses like a 7 in 1 body wash and it's just one bottle of something that you Squirt all over your whole body and just call it a day.

Dr. Norman Swan (14:04)

My habits in the shower will go to my grave with me.

Norman Swan (14:10)

You gotta keep something back from the audience. You just gotta leave them wanting more.

Dr. Norman Swan (14:14)

That's right. So the answer for Steve is if you've got a healthy scalp, you don't have dandruff, you don't have psoriasis, you're probably not doing yourself any harm if you decide you're going to wash your hair at a much lower frequency than otherwise or even not at all, according to some people who are. No poos.

Norman Swan (14:29)

Absolutely. And I think probably best to get your advice from a dermatologist and not from the marketing copy put out by shampoo and conditioner companies.

Dr. Norman Swan (14:38)

What's in the mailbag?

Norman Swan (14:39)

So in the mailbag, which is where you can send your questions thatrashbc.net au send us your questions. Send us your feedback. There are two hayfever. N equals one studies Norman. Well, N equals one questions.

Dr. Norman Swan (14:52)

I suppose one comes from Stephanie.

Norman Swan (14:54)

Stephanie says my husband is Australian and grew up here, but we now live in Europe. It turns out his hay fever functions equally well in both hemispheres. So sadly he did not have the same luck as Norman. You mentioned Norman when we talked about hay fever. Our episode that came out a couple of weeks ago that you don't get hayfever anymore in Australia, even though you got it as a boy in Scotland. Anyway, Stephanie says one sure fire way to prevent him from having symptoms. Are you ready for this?

Dr. Norman Swan (15:21)

Yeah. What is it?

Norman Swan (15:22)

Play rugby.

Dr. Norman Swan (15:23)

Oh really?

Norman Swan (15:24)

He never has symptoms so he rubs.

Dr. Norman Swan (15:27)

Himself through the grass. It's like a dog sort of rolling around in the grass.

Norman Swan (15:31)

Stephanie says he never has symptoms during or after a game, regardless of how long he spends outside. Even though rugby's a winter sport, it is played almost all year round here with an extra break because it gets too cold. Nobody wants to play on a frozen pitch. Yet if we go on a not so strenuous outing during summer, he's miserable and suffering within minutes. And it's not a matter of location. The home pitch is right next to a lake and if we are there just to enjoy the weather, hayfever. If he plays rugby completely fine. What is going on here?

Dr. Norman Swan (16:02)

Well, you can only speculate here, exercising and high throughput through the airways that you might just be expelling the spores at a high rate. The other theoretical aspect with Stephanie's husband is that exercise has an anti inflammatory effect on the immune system and therefore that might be part of it. Oh, the Other is that it's a form of immunotherapy that he's getting in amongst the pollens and that's affecting his immune system and dampening it down. But it's obviously a very temporary effect because if he's not doing exercise, he's getting his hay fever.

Norman Swan (16:36)

Maybe he just doesn't want to go for a walk with his wife Stephanie.

Dr. Norman Swan (16:41)

I'd walk a long way with Stephanie, I'm sure.

Norman Swan (16:45)

By the lake and everything.

Dr. Norman Swan (16:46)

Yeah, sounds very romantic.

Norman Swan (16:48)

Sorry that we can't give you a more definitive answer, Stephanie, but that is a true medical mystery. I very much enjoyed that one.

Dr. Norman Swan (16:54)

Yeah, rugby is immunotherapy.

Norman Swan (16:56)

Well, our other email comes from Sue Ellen who says, I suffer from hay fever every year from late February to sometime in May. And I have accidentally discovered that taking fish oil tablets at maximum dose during particularly harsh times helps a lot. There's significant relief for my eyes and nose and I'm assuming it's the anti inflammatory properties. I was taking fish oil initially because I wasn't eating enough fish and what a difference it made to the lighter stages of this issue. I highly recommend it. Norman, your response please? Because I feel like I have heard you poo, pooing fish oil in the past.

Dr. Norman Swan (17:30)

We're in a no poo episode. No, there's no question that fish oil at the right dose, which is probably higher than they recommend on the packet, does have anti inflammatory effects on the body. So it does affect the immune system. The skepticism about fish oil is whether or not it prevents coronary heart disease, heart attacks and so on. And there the evidence is pretty light on. And the better the study done on fish oil to prevent coronary heart disease, the less likely it is to do so. But there is no question that in higher doses it does have an anti inflammatory effect.

Norman Swan (18:04)

Well, there you go, Sue Ellen. Keep on knocking back those tablets, I guess. Thank you so much for your emails and keep your questions coming. Thatrashbc.net.au See you next week.

Dr. Norman Swan (18:14)

See you then, Sam.