The author of the story kindly submitted here begins by writing, "I was Subject 26 in testing a living bacterial skin tonic, developed by AOBiome, a biotech start-up in Cambridge, Mass. The tonic looks, feels and tastes like water, but each spray bottle of AO+ Refreshing Cosmetic Mist contains billions of cultivated Nitrosomonas eutropha, an ammonia-oxidizing bacteria (AOB) that is most commonly found in dirt and untreated water. AOBiome scientists hypothesize that it once lived happily on us too — before we started washing it away with soap and shampoo." So what we are particularly talking about here is an early-phase human trial of a cosmetic product (which is regulated in the United States by the Food and Drug Administration under the Food, Drugs, and Cosmetics Act) which may or may not have the benefits claimed by the manufacturer. The trial is to find out if the new cosmetic does anything at all beneficial, without too much harm. Getting news coverage like this is of course public relations gold for the manufacturer.
I read most of the comments here before reading the article and then posting my later comment. A lot of the comments revolve around the issue of the health effects of "modern" human life. All epidemiological evidence to date suggests that living like a middle-class or wealthier person from a developed country is good for health. An article in a series on Slate, "Why Are You Not Dead Yet? Life expectancy doubled in past 150 years. Here’s why."[1] refers to the steady long-term upward trend in healthy lifespan in the United States. Whatever we are doing about washing our bodies or our hair so far doesn't have any harmful effect that isn't swamped by the generally helpful effect of all the other changes of modern life. Life expectancy at age 40, at age 60, and at even higher ages is still rising throughout the developed countries of the world.[2] The overall trends are so favorable to further improvement to general health that if the observed facts about people who are already born and conservatively projected current trends continue, we can expect that girls born since 2000 in the developed world are more likely than not to reach the age of 100, with boys likely to enjoy lifespans almost as long. The article "The Biodemography of Human Ageing"[3] by James Vaupel, originally published in the journal Nature in 2010, is a good current reference on the subject. Vaupel is one of the leading scholars on the demography of aging and how to adjust for time trends in life expectancy. His striking finding is "Humans are living longer than ever before. In fact, newborn children in high-income countries can expect to live to more than 100 years. Starting in the mid-1800s, human longevity has increased dramatically and life expectancy is increasing by an average of six hours a day."[4]
On evolutionary grounds, there is every reason to expect that human beings have haphazard adaptations through natural selection to survive to reproductive age despite a world full of microorganisms that were neither created nor evolved to benefit human beings, but rather just to survive and reproduce themselves. There is no evidence whatever that there are any large number of bacterial species or other microorganisms that are actively "beneficial" for human beings, rather than simply being well tolerated by human hosts. To live to healthy old age and greater enjoyment of the natural world and all its wonders, human beings may very well be better off continuing the human way of shaping their environments and culturally transmitting environmental interventions that lead to "unnaturally" good health and longevity.
AFTER EDIT, TO RESPOND TO QUESTION BELOW: Yes, I am saying there is weak or no evidence of "beneficial" bacteria for human beings. This is to be expected from the consilient findings of evolutionary theory. (Human beings have had to live in highly microbe-free environments, for various reasons.) I am specifically asking for evidence, from medical review articles, that there are well accepted "beneficial" skin microbes. Which are they? What is the evidence that shows the benefit?
The author of the article seems somewhat convinced by her personally experienced anecdote. It would of course take much more long-term study (not to mention more double-blind study designs) before we will be sure what is beneficial for human skin in particular and human health in general by way of applying bacteria intentionally to our skins. Suffice it to say that I am not afraid of washing my hands with soap nor afraid of washing my hair with shampoo. The book The Checklist Manifesto reports on an experimental study in a poor country of promoting hand-washing with soap, and how that showed evidence of improving health outcomes. Let's not throw out good hygiene with the bath water until more research has been completed on this interesting topic.
I believe you're conflating two issues. Few people argue against hand-washing with soap. The benefits are proven.
But where did you get the notion that washing the whole body with soap is beneficial or even benign? You've cited many studies, but they all deal with aging and not with skin flora.
Skin flora is complex. I know of no scientific study that has looked into whether skin flora or hygiene is improved by full body soap washing.
Full body soap washing began in the early part of the 20th century, following a steady marketing campaign with ads such as this:
At the time, people bathed little. When they bath more frequently, with soap, odour improved. Soap usage became widespread.
It seemed a reasonable inference that soap was the cause. Particularly since if you stop using soap, you get smellier, even if you bathe.
I believe this inference is wrong. I stopped using soap in 2011. For the first 2-3 weeks, I smelled worse. Then I smelled better. I have had practically no BO since, even in the most sensitive regions. Women have confirmed that I smell good, spontaneously. If you saw me, you would never know I don't use soap.
I'm using an N of 1, but it seemed like the bacterial balance of my skin improved. It also became less oily. I can only speak to my own example, but I have seen many reports from others who went through the same transition as me.
So I'll repeat: where is your evidence that full-body soap washing offers benefits? Are there any scientific studies that support your position?
My hypothesis is that full body soap makes us worse off and that we don't realize this due to the transition period. Our habit was begun by marketing and cemented by tradition. (our parents washed us when we were young)
Edit: I just noticed this sentence:
"There is no evidence whatever that there are any large number of bacterial species or other microorganisms that are actively "beneficial" for human beings"
This seems rather unsupported. Are you saying we do not require intestinal or skin flora?
Second edit: In response to your edit, I found this article:
"I stopped using soap in 2011. For the first 2-3 weeks, I smelled worse. Then I smelled better. I have had practically no BO since, even in the most sensitive regions. Women have confirmed that I smell good, spontaneously. If you saw me, you would never know I don't use soap."
Do you still wash your hair? Do you still shower (i.e. rinse) once a day? How do you wash after when you're especially dirty? (e.g. dirt, grease, etc.)
I'd be curious to hear about your hygiene routine in a little more details.
I shower every day. Sometimes twice if I've done something that made me sweat or it's a warm day and I want a cold shower.
I occasionally wash my hair with baking soda then apple cider vinegar. It was what other people doing the same thing use. Hair is very clean and soft after that.
The frequency of the hair wash depends on how my hair is. If I eat, sleep and rest well, it stays clean for a week or more. If I eat poorly it gets greasy faster and I wash it more.
I use soap to wash my hands after using the washroom and during food preparation, or when something major has dirtied my hands.
Otherwise, no soap on my body. Subjectively, odour improved in all the sensitive areas. I used to notice BO in my armpits and a few areas I won't name. Now I don't.
As I said, this improvement has been confirmed by spontaneous compliments.
Thanks for the link in answer to my question. A tip: if you know the title of an article (here, "Skin microbiota: a source of disease or defence"), and put that article title into a Google Scholar search, you will often find a copy of the article that is not behind a paywall (here, because it is also hosted on the Pub Med Central public access website). Now I have to read the full text of the article, and see what subsequent articles say on the issue.
Another anecdote, I had a very bad acne back in secondary school, I tried everything and I did not get better. Our of frustration I stopped all treatment and I stopped using soap in my face. At some point the acne fixed itself but I never got back to the soap. All in all I have been soap free in my face for 15 years, I do shave with hot water.
Just wanted to make N = 2: I haven't used soap or shampoo since 2010. My skin and hair feel and look great and nobody's ever said anything about my smell.
I honestly think I won't use soap or shampoo for the rest of my life.
Look, I'm not saying you stink, but you need to smell hobo-levels for people to speak up about something like this; a smell level way beyond what would have negative social repercussions.
What I'm saying is: even if you smell a little, not enough to put people over that (huge) threshold to bring it up to you (note the recurring 'Ask Abby' topic of 'how do I tell my colleague/spouse/friend they smell'), you'll still be known as 'that smelly guy'.
(again, not saying you smell, just that 'nobody ever told me' is not enough to believe you don't, and being falsely informed of this topic will have real consequences for people).
I've basically had the same experience that graeme has wrote about in his comments earlier: people have actually complimented me on my smell without knowing that I don't use soap, and I've been in a long-term relationship (3+ years) without me telling my partner that I'm not soaping and them not saying anything to me.
I think it's also important to point out that I still shower or bathe every day (and additionally after I work out), so I'm still getting clean.* I just don't use soap, just lots of water and scrub the hell out of my skin with a washcloth.
*Yes, here we could parse out what I mean by "clean" but you'll just have to trust me on this one.
Much of this discussion has been on soap, and for me personally using soap every day everywhere just dries out my skin, so I use soap daily only in 'strategic locations' (on a meta note, I can't believe I'm actually having a conversation about this). But what I wonder from all the people in this thread saying they don't use soap with a 'naturalism' based argument (if I'm understanding them/you on the reason correctly), do you also not use deodorant? Because you can wash/rinse 3 times a day, even with soap, but (sorry for gross visuals) armpit sweat is going to smell over the course of a day, especially the sort of sweat the comes from stress and not 'just' from being warm. And that smell comes from bacteria too, 'natural' bacteria.
Some studies claim it's not that bacteria are good, but that the lack of them causes an imbalance in our immune system, as they have evolved over millenia to co-exist with this huge diverse flora of bacteria. Apparently, if they're absent, immune me can run amok.
I read most of the comments here before reading the article and then posting my later comment. A lot of the comments revolve around the issue of the health effects of "modern" human life. All epidemiological evidence to date suggests that living like a middle-class or wealthier person from a developed country is good for health. An article in a series on Slate, "Why Are You Not Dead Yet? Life expectancy doubled in past 150 years. Here’s why."[1] refers to the steady long-term upward trend in healthy lifespan in the United States. Whatever we are doing about washing our bodies or our hair so far doesn't have any harmful effect that isn't swamped by the generally helpful effect of all the other changes of modern life. Life expectancy at age 40, at age 60, and at even higher ages is still rising throughout the developed countries of the world.[2] The overall trends are so favorable to further improvement to general health that if the observed facts about people who are already born and conservatively projected current trends continue, we can expect that girls born since 2000 in the developed world are more likely than not to reach the age of 100, with boys likely to enjoy lifespans almost as long. The article "The Biodemography of Human Ageing"[3] by James Vaupel, originally published in the journal Nature in 2010, is a good current reference on the subject. Vaupel is one of the leading scholars on the demography of aging and how to adjust for time trends in life expectancy. His striking finding is "Humans are living longer than ever before. In fact, newborn children in high-income countries can expect to live to more than 100 years. Starting in the mid-1800s, human longevity has increased dramatically and life expectancy is increasing by an average of six hours a day."[4]
On evolutionary grounds, there is every reason to expect that human beings have haphazard adaptations through natural selection to survive to reproductive age despite a world full of microorganisms that were neither created nor evolved to benefit human beings, but rather just to survive and reproduce themselves. There is no evidence whatever that there are any large number of bacterial species or other microorganisms that are actively "beneficial" for human beings, rather than simply being well tolerated by human hosts. To live to healthy old age and greater enjoyment of the natural world and all its wonders, human beings may very well be better off continuing the human way of shaping their environments and culturally transmitting environmental interventions that lead to "unnaturally" good health and longevity.
AFTER EDIT, TO RESPOND TO QUESTION BELOW: Yes, I am saying there is weak or no evidence of "beneficial" bacteria for human beings. This is to be expected from the consilient findings of evolutionary theory. (Human beings have had to live in highly microbe-free environments, for various reasons.) I am specifically asking for evidence, from medical review articles, that there are well accepted "beneficial" skin microbes. Which are they? What is the evidence that shows the benefit?
The author of the article seems somewhat convinced by her personally experienced anecdote. It would of course take much more long-term study (not to mention more double-blind study designs) before we will be sure what is beneficial for human skin in particular and human health in general by way of applying bacteria intentionally to our skins. Suffice it to say that I am not afraid of washing my hands with soap nor afraid of washing my hair with shampoo. The book The Checklist Manifesto reports on an experimental study in a poor country of promoting hand-washing with soap, and how that showed evidence of improving health outcomes. Let's not throw out good hygiene with the bath water until more research has been completed on this interesting topic.
[1] http://www.slate.com/articles/health_and_science/science_of_...
[2] http://www.nature.com/scientificamerican/journal/v307/n3/box...
[3] http://www.demographic-challenge.com/files/downloads/2eb51e2...
[4] http://www.prb.org/Journalists/Webcasts/2010/humanlongevity....