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Anna Crist

student researcher , University of Oregon

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Purell now, Bacteri-ell later?

The hygiene hypothesis, the idea that “too much cleanliness prevents the development of a well-balanced immune response”(Sironi and Clerici, 2010), has received a lot of support and also criticism. It has recently been challenged by the hypothesis of “early immune challenge”, which states that a lack of appropriate immune stimulation during early childhood might account for the increased development of allergies in industrialized countries (Kramer et al, 2013). This proposal places less emphasis on excessive hygienic practices and focuses more on the insufficient exposure to specific environmental microbes, particularly those from non-urban environments, as the reason behind the rise of atopic disease. While different, both hypotheses point to the beneficial health affects of some microbes.

What do you think is the reason for increased allergy levels in industrialized countries? Do you think that a concoction of the “right” microbial species in the form of a lotion, drink, or inhalant (aka "Bacteri-ell") could be a future replacement for natural exposure to beneficial microbes?
Instead of using hand sanitizers like Purell, do you see a future where people from some regions of the world are unsanitizing their hands with “Bacteri-ell”?

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    Apr 30 2013: As many people have brought up, we know very little about microbes and even if we did, it's not as simple as "good" microbes and "bad" microbes. This makes me skeptical that developing a single product like "Bacteriell" would be useful for the kinds of services we are hoping it would deliver (ex. reduce certain types of chronic diseases). Additionally, the premise of the argument seems to be that young kids need exposure to microbes. It's unclear whether "adding" microbes to your skin later in life will prove effective. Such a product would thus need to be catered to young children and probably wouldn't be analogous to Purell, but more like a supplement for babies in skin cream form.

    To address a point that's been raised several times--the nature lover in me wants to advocate for more time outdoors. We should be reconnecting with nature instead of producing synthesized and probably sub-par replacements. On the other hand, I had the privilege of growing up where I had almost constant access to the outdoors; my parents could send me outside without worrying that I would be unsafe. The reality is that most people in the US (and increasingly the world) live in cities, and with the wealth gap increasing, parents may not have the luxury of bringing their children out to the wilderness everyday. Because of this, my tendency is to lean toward a city planning solution over a commercial product. Emerging concepts of eco-cities take sustainability into account with city design. However, the focus is still on limiting impacts rather than being proactive about conservation. Most plans for parks or green areas focus on recreation and aesthetics over maintaining some kind of ecological diversity, both at the macro-fauna level and the microbial one. This kind of a focus could serve several purposes, including providing a place for kids to be exposed to microbes as well as reducing biotic homogenization. Any thoughts on this? Or existing examples?
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      Apr 30 2013: I agree with you Mika. I'm not so sure about adding "Bacteriell" alter on in adults will help to reduce certain diseases. In a mean while, we need more time and research on studying skin and human microbiome. I love outdoor activities. I exposed myself with nature most of the time when I was young. I think this definitely is one of the reason I rarely get sick. I think most of the reasons people live in the cities don't want kids to be outside because the severe air pollution in the city. After get used to Eugene extremely clean air, every time I went back to Taipei, Taiwan, I got skin and eye allergies. So my personal experience kind of tell me that my microbiome on my body has changed probably throughout these several years I lived in Eugene.

      I like your idea about city planning solution in the big cities. We all know city parks / gardens are really important to kids live in cities. To add on that, maybe a small area of "educational" ecosystem (include microbials) right beside the the park or gardens so that both parents and children are more willing to reconnect with the mother nature.
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      Apr 30 2013: The connection to natural areas within cities, or even constructed parks, is something I find very interesting. I also like the idea of looking to exposure in natural environments as a way to built strong immune systems through exposure to a variety of organisms found here. As a few other people have said below, until we know which microbes benefit our health I think looking to the Earth's natural environment, which we've evolved with over a long period of time, is currently the best bet for building strong immune systems in young people.
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    Apr 30 2013: Many people in this conversation have pointed out that it would be a better idea to encourage people to stray away from the use of antibiotics, rather than introduce themselves to microorganisms more frequently. While this is probably a good idea, the focus of the question is whether or not it is possible to develop immunity to microorganisms if you weren't exposed to them at a young age. We don't know enough about microbes at this point to be able to determine whether applying a culture of bacteria to ourselves would result in positive or negative outcomes, however the idea is a step in the right direction. Once we have determined which microbes have definitively positive influences on humans, it would be a good idea to allow ourselves to be exposed to them regularly. It may be hard to keep the organisms alive in a way that mimics purell, because nutrients may become limited quickly. In what other ways could we expose ourselves to these organisms, without having to worry that the culture will die?
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      Apr 30 2013: I agree that it would be hard to keep microbes in a lotion (they are already hard to culture in a lab as it is.) I mentioned to Ben Story that maybe humans themselves could be "microbe donors." Maybe without going so far as fecal transplants... But maybe children could just come in contact with people who are known to have a more diverse "microbe cloud" (and we had a future way to test this), say those who live on farms, and they could be exposed to the helpful microbes that way (which happens to a certain extent anyway, this would just be more deliberate and have more science behind it.) Also, using animals as carriers could be another way. Making sure children are taken to petting zoos with animals who are known to have beneficial microbes (like frogs!) :)
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      Apr 30 2013: Thinking about other ways to get exposure to microbes I kept thinking that the best ways to increase people's environmental exposure would be one that was sort of lo tech and easy and cheap to do. I was imagining something along the lines of a petting zoo, in fact it could just totally be a normal petting zoo. A place where children would be exposed to a variety of microbes naturally through no extra action of their own. Sticking to this basic approach is definitely less exciting than the development of some sort of bacterial concentrate to simulate natural exposure, but I think it would be far easier than isolating exactly which microbes someone needs to be exposed to in order to develop properly and extracting from the concoction the ones deemed unnecessary.
      The most challenging part of this would probably be the public health front of it in convincing parents to let their kids be kids and get dirty. I think in general that the best approach to solving problems like this is to utilize a natural approach as much as possible if it is effective, and I think that in this case that a traditional exposure regime would be the safest and most effective plan of action.
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    Apr 30 2013: Let your children eat dirt and for God's sake stop worming then. We evolved covered in dirt and with our gut full of parasites. You should only bother them if they start to bother you.
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      Apr 30 2013: That's why my grand kids and I always eat all of our meals off the floor, I've never had allergies and if it was good enough for me growing up then it's good enough for them LOL!

      God Bless

      - Todd C.
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      May 1 2013: This is excellent advice, Peter!
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    Apr 30 2013: I'm going to have to play the devil's advocate for this question.

    Although, studies support this theory, to me the premise alone seems a little unrealistic. I know very few people that use Purell (or similar) products on a very consistent basis, that one could consider over use. The moment a user's hands dry and they touch something (a book, a door handle, a railing, a chair, etc...) the bacteria living there are immediately transferred to the skin. Essentially, even a handshake would completely reverse the bacteria massacre that said individual had just preformed. It seems unrealistic that anybody could have sterile hands 24/7.

    I would also like to bring up an alternative hypothesis.that perhaps the disruption of skin microbiota is not significant in the development in these allergies. In the specific study cited by Anna, the researchers looked a particular antimicrobial chemical, Triclosan. They correlated its presence with allergic reactions. Although this revelation supports the conclusion reached by the authors, it doesn't rule out one basic alternative. Perhaps the Triclosan itself is causing an increase in allergies by aggravating the immune system. Studies have shown Triclosan to cause allergic reactions in some individuals.

    This conclusion would tie in well with another hypothesis, the pool chlorine hypothesis. The pool chlorine hypothesis suggests that an increase in time spent in chlorinated pools is correlated with an increase in asthma rates. The authors of this hypothesis suggest that is the chlorine per se that is causing the asthma.

    I believe that perhaps this is a similar situation to that involving Triclosan and that it is not the lack of microbes that are causing the problems, but the Triclosan itself.

    -Bhutani, T.; Jacob, SE. (May 2009). "Triclosan: a potential allergen in suture-line allergic contact dermatitis".
    -Campbell, L.; Zirwas, MJ. (Dec 2006). "Triclosan". Dermatitis
    -http://en.wikipedia.org/wiki/Pool_chlorine_hypothesis
    • Apr 30 2013: I agree with Ben, I don't think people are over using Purell or any other antibacterial substances, nor do I think we should cut down on using them or the cleanliness methods we have been taught. For example if people in food service started washing their hands less, I think many more people would get sick then the amount that would build up a stronger immunity. I think one of the biggest reasons people are getting sick more often is due to overuse of antibiotics. whether it's a doctor prescribing an antibiotic for a viral infection or a parent giving a child medication for something their body can fight on their own, people's immune systems are getting weaker. Instead of looking at adding bacteria to a person with a weaker immune system, maybe we should start by decreasing the medication use and then we will see a decrease in people with so many allergies and other serious conditions.
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        Apr 30 2013: I don't think that anyone is advocating that people in the food service industry start washing their hands less. I agree with your point that antibiotics is a contributing factor, however I think that it is a lack of early exposure to microbes that can cause lasting health consequences.
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          Apr 30 2013: I agree, we need exposure to all kinds of microbes at an early age so that our body's natural immune responses can be become stronger. It would be so cool to one day have the research and knowledge about what microbes are vital to be exposed to at an earlier age. If we could obtain this knowledge, we could facilitate exposure in people that were born with compromised immune systems, such as premature babies or cesarean births.
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          Apr 30 2013: Yes! Exposure to the microbial environment is extremely important in development of a child's immune system. Microbes naturally found in soil may be linked to releasing serotonin, changing a persons mood.
          http://www.medicalnewstoday.com/releases/66838.php
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          Apr 30 2013: Noel, that is very interesting! There may be a link between immune system imbalances and mood disorders.
        • Apr 30 2013: That is probably very true Eleni! I am not against exposing people to more microbes. I am exposed to all kinds every day at my little zoo of a home! I'm also thankful I have Purell and antibacterial soaps to use after exposing myself to these other microbial environments because it keeps me from getting sick. I think people go from one extreme to the next when things are discovered so my fear is if it's pushed that we are "too clean" and need more exposure to bacteria that people will start being a lot less clean.
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      Apr 30 2013: Thanks everyone!
      Ben- What I think you are missing that Eleni and Ashleigh pointed out is that exposure to microbes at an early age is what is important. I am certainly not trying to suggest that people have sterile hands because of overuse of Purell, "Bacteri-ell" is just a play on words. I am proposing that a lack of exposure to certain key microbes at an early age, due to an overall less natural environment in industrialized regions, is the cause behind increased frequency of allergies. You raise an interesting point that a handshake could reverse a lack of exposure to certain microbes. Maybe people who have a more complete "microbe cloud" (in the words of Jonathan Eisen), could serve as "microbe donors" to children who don't have access to the mrobe diversity in nature, such as that you would find on a farm.

      Your idea that chlorine and Triclosan themselves are the cause of allergies is definitely something to consider.

      Asleigh: Your comment is exactly what I am getting at! :) My idea definitely relies on our future ability to gain the knowledge you mentioned.
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    Apr 29 2013: Studies have shown that not just humans, but all mammals have microbes on their skin in the order of trillions, with thousands of different species. Also, studies have shown that when we have a more biologically diverse set of microbes, then we have a better immune response to many different pathogens and antigens. But I doubt that our bodies would be ready for an onslaught of microbes in gel form.
    We do need more helpful microbes on our skin, and in our gut, but disrupting the biodiversity by adding selected microbes we think are most important could upset our body's ecosystem. It could become, in a sense, like an invasive species problem on our skin.
    This is a good idea, but may be better used as a medical treatment for those with problems associated with possible "microbe deficiency." Or maybe it would be better for people to take more trips out into the country and get to know the ecosystem that surrounds the artificial one we made.

    Check out this Nature article on allergies and microbes. There's some good background on the subject here.
    http://www.nature.com/nm/journal/v18/n4/full/nm.2723.html
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      Apr 30 2013: Good point! I did not think about the alteration of microbiome on our skin. I guess it might substitute for probiotic.
  • Apr 29 2013: According to the National Institute of Health it was found that from 1988-1994 more than 50% of Americans from ages 6-59 were sensitive to at least one allergen. However, a similar study done in 1980 found rates 2-5 times lower. The reason for this large increase in allergens is thought to be the more sterile lifestyles we now live. By disinfecting everything around us, we are severely limiting the amount of bacteria we are exposed to.

    Being exposed to different bacteria at a young age is very similar to receiving a vaccination. A vaccination works by stimulating an individual's immune system in order to develop an immunity to a pathogen. Our bodies immune systems are formed by being exposed to seemingly harmless substances around us, such as pollen, animals, foods, etc. When we do not receive these "vaccinations" of harmless substances at a young age, it can result in allergies later in life when they are finally encountered.
    Exposure to certain germs and allergens at a young age are important in the development of our immune systems. Without these exposures our bodies will be unable to fight off everyday substances later in life.
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      Apr 30 2013: Julia,
      That is a fantastic summary of the hygiene hypothesis and why it really seems like it is addressing the newer early immune hypothesis with its premise. It got me to thinking though, since so much of both hypotheses are based on early exposure and the conditioning of our immune systems for the rest of our lives, I have to wonder if there is any hope to the strategy of introducing the missing agents later in life in order to cure allergies or other auto immune diseases. I bet that if the supplementation of microbes, like with the "Bacteri-ell" discussed by Anna, was done early enough while the immune system was still plastic, it would be possible to avoid the development of autoimmune diseases including allergies. If this window of developmental plasticity is missed though, I don't think that this sort of treatment would be effective.
      I would love to know if there is any evidence that autoimmune diseases can be treated in this way later in life though, it isn't something I really follow so it wouldn't surprise me if there were some new developments since last I heard about the general theory.
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        Apr 30 2013: Thanks for your input! In my head I imagined parents lathering up their children with Bacteria-ell lotion, instead of trying to keep them germ-free with sanitizing agents like Purell.

        Support for the “hypothesis of early immune challenge” comes from a study by Douwes, et al (2008) which found that children raised on farms were not afflicted with asthma and neurodermitis as much as children who were raised in cities. This observation was even associated with contact of pregnant women to animals and soil, suggesting that prenatal exposure to certain microbes is also important in disease prevention. I thought this was really interesting!

        I am out of time right now so I will get back to you about adult studies I found! Or maybe someone else can contribute to that part of your comment.
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          Apr 30 2013: I guess the main thing that had me confused about the early immune challenge was how it was really differentiated from the older hygiene hypothesis. You said in the intro that "[The early immune challenge hypothesis] places less emphasis on excessive hygienic practices and focuses more on the insufficient exposure to specific environmental microbes," but wouldn't this lower exposure to microbes be a direct effect of the hygiene hypothesis. I guess it seems like the main differentiation between the two is where the microbes are coming from then, be it urban or rural areas, but I still feel like I'm missing some larger point of distinction between the two.
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        Apr 30 2013: I was also confused about the difference between the two at first. This quote, which I also mentioned to someone else, will hopefully help clear things up a little.

        "The risk of developing allergies is not necessarily caused by a lack of bugs and parasites in the environment per se, but rather by a lack of certain organisms that have, over the course of evolution, trained our immune system to be more tolerant.” (Rook et al, 2009)

        The first part (up until "per se") describes the hygiene hypothesis, or the idea that not being exposed to enough microbes *in general*, due to more sanitation, causes us to be more prone to certain diseases. Whereas the second part of the quote is more along the lines of the "early immune challege" hypothesis, the idea that lack of exposure to SPECIFIC bacteria is the cause of increased allergies. It's definitely a subtle difference, but I hope this helps!
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          Apr 30 2013: I was wondering that as well, and that clears it up for me at least. I think the early immune challenge hypothesis sounds more plausible, as i suspect that certain distinct specific microbes are what make the difference- however, it's possible that so many different specific microbes are needed that this nearly replicates the hygiene hypothesis. I suppose it depends on where one draws the line between "many many specific microbes" vs "a general diversity of microbes," however, with that said, i imagine more than a few denizens of our microbiome are innocuous or at least have no noticeable effect on human immune response.
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    Jon Cox

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    Apr 30 2013: "What do you think is the reason for increased allergy levels in industrialized countries?"

    It's a little off topic but one interesting reason is that back in the day, in the U.S. anyway, we chose to plant species of trees in our cities that happened to release very little pollen into the immediate atmosphere. Well 50 or 60 years ago we began planting more and more species in our urban environments that happen to produce LOTS of pollen. In addition to this, because they do not drop seedpods or fruit and are thus less "messy", male trees (some species produce flowers with both male and female parts while other species are made up of individuals which are either male OR female) are often very popular, and guess what male trees might make lots and lots of.... POLLEN. Our choice of landscaping in the last half century or so has greatly contributed to our allergy troubles.

    Here's a good article about it: http://www.nytimes.com/2010/04/06/opinion/06ogren.html
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      Apr 30 2013: Interesting point Jon! I think this is a very good explanation for increases in allergies in industrialized countries. I would think that we'd start to develop an immune response to this increased pollen. Now I know that 50-60 years in the evolutionary scheme of things, but seeing how quickly microbes can develop resistances to antibiotics (penicilin comes to mind), I would think that our own immune systems could adapt as quickly. I know that we do have many more cellular processes than prokaryotic organisms, which may be accounting for our increased time to develop allergic resistances?
    • May 1 2013: I agree. I believe that the increase in allergies in industrialized areas is due to multiple factors, not just the over-cleansing-of-bacteria. True, much has been pushed forth in terms of understanding the micro-biome, but I believe that a combination of ingesting pesticide/genetically-altered foods over multiple years, planting habits in industrialized societies, AND over-cleansing of our micro-biome have contributed to the increasing rate of allergies. I bet if we tackle this problem directly, we'll discover many more factors that have added to this condition, which exist at multiple scales, from the super-micro to the super-macro.
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        May 1 2013: Poor air quality is another major contributor. So yeah there are tons of reasons! And thinking about what Mario said about evolution of resistance to allergens in our immune systems, we should keep in mind that humans have rewritten the book when it comes to evolution thanks to medicine and technology, etc. Natural selection pretty much doesn't apply anymore. Being susceptible to pollen allergies doesn't decrease our chances of surviving and reproducing. Maybe it did in the past, but not anymore. A genetic mutation COULD arise that makes a person immune to pollen, and maybe this happens already, but they will not be more likely to survive and reproduce than anyone else.
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    Apr 30 2013: I suppose that it is possible for a probiotic product to be developing that would artificially inoculate our microbiome with the right microbes. My main concern is, how do we know what the right microbes are? We currently know so very little about microbial biodiversity. Even though thousands of species of microbes live in and on our bodies, even though we ARE part microbe in a sense, there is a lot we do not know. Is there a possibility that someone will attempt to develop a probiotic product (aka Bacteriell) and that without adequate knowledge of microbial ecology, it will be woefully ineffective, or even detrimental to our health? We have to tread carefully here.... there's a lot of potential in this idea, provided some pharmaceutical company isn't too hasty.
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      Apr 30 2013: Excellent point! My hope is that will be able to gain this knowledge in the future. It would definitely be scary if someone tried to make this product without adequate research beforehand!
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      Apr 30 2013: I love your point! Yes, there is a great potentiality of microbes that can influence our health. Before knowing the effect the bacteria on our body, we cannot make many microbe products in our food. In china, many yogurts state that it includes probiotics that are good for gastrointestinal function or have some other benefits. But can we make sure they are only good for our health, no detrimental effects or other influences?
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    Apr 30 2013: Thanks for all the great input! Here are the links to the two studies I referenced in the conversation starter. I had a glitch when uploading the talk so I didn't include them.

    1. Manuela Sironi, Mario Clerici, The hygiene hypothesis: an evolutionary perspective, Microbes and Infection, Volume 12, Issue 6, June 2010, Pages 421-427, ISSN 1286-4579, 10.1016/j.micinf.2010.02.002.
    (http://www.sciencedirect.com/science/article/pii/S128645791000050X)

    2. A. Kramer, S. Bekeschus, B.M. Bröker, H. Schleibinger, B. Razavi, O. Assadian, Maintaining health by balancing microbial exposure and prevention of infection: the hygiene hypothesis versus the hypothesis of early immune challenge, Journal of Hospital Infection, Volume 83, Supplement 1, February 2013, Pages S29-S34, ISSN 0195-6701, 10.1016/S0195-6701(13)60007-9.
    (http://www.sciencedirect.com/science/article/pii/S0195670113600079)
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    Apr 30 2013: It really is an understatement when we say microbes are important for the proper functioning of ecosystems, let alone us. Not only do they supply vital supporting ecosystem services with carbon recycling and nitrogen fixation, they also help build stronger immune systems in humans.

    Sadly, many of us only view microbes as pathogens, and not accomplices to a healthy lifestyle. The rise of allergies in industrialized countries could be due to the over use of antibiotics and cleaners that exterminate microbes. Thus, a child growing in an industrialized country may become more susceptible to allergic diseases than one growing up in a developing country due the lack of natural immune system development.

    Surely we can take probiotic supplements, but does that reverse the poor immune system of adults? Maybe those who would prosper most from a “Bacteri-ell” would be children.

    Exposure to microorganisms and other antigens (proteins from the exine of pollen, animal proteins, and foods) at an early age acts as a natural vaccination. Our body’s ability to produce antibodies and defend itself is a remarkable process. Bacteri-ell is already around us, we just need to be exposed to it at the right time.
    • Apr 30 2013: The point that most people only know bacteria as pathogens is a major issue for many things, but personal health and immune system function especially. I think a product like Bacteri-ell could have huge impacts on public perception however.

      Despite the potential benefits, I find that strategy ironic. I the same way fake tans or daily vitamins can be sold, Bacteri-ell would too. Create a solution to problem, then let the consumer create the problem for them self... the irony stemming from the good intentions to turn a profit.
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        Apr 30 2013: I never really thought of it that may. Maybe Bacteri-ell may become the norm when we recognize the importance of our microbial cloud.
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      May 1 2013: I do agree with the idea that too much cleanliness actually decreases the ability of immune response. According to a medical investigation in German, children in rural areas are less likely to suffer from allergies than children from urban areas. This is because rural children have more chance to get contact with nature. When they play with mud, their skin will contact with diverse microbes in the soil. The development of human’s immune system depends on external stimuli. Immunological strength is proportional to the contact with outside environment. The more chance of contact with the outside stimuli, the stronger the immunological strength will be. Thus, rural children’s immune system will establish its understanding of diverse bacteria from childhood, resulting in certain diseases resistance. Most children will not get skin allergies easily. I am not sure the applicability of “bacteri-ell” substitute that you pointed out. However, I think this is a good starting point, since people already did a good job on putting lactic acid bacteria and yeast into yogurt. In order to increase our immune response, I think people should increase their contact with nature resources, and do not pursue too much cleanliness by over-use antibiotics. What is more, educate the public that microbes are not always doing bad things and lead them to a better lifestyle to live with beneficial microbes.
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    May 1 2013: In case folks have not seen it yet here is a greatTEDxEugene talk by Brendan Bohannan on the human microbiome: http://www.youtube.com/watch?v=Dfy2qYfUWE0
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      May 1 2013: I really liked the part at the end when he tells us that we need to be "affiliated with the ciliated" Good talk!
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    Apr 30 2013: I found a program through The Human Food Project that works to analyze different microbes found in participants' guts and associate them with different lifestyle patterns (ie vegetarian, c section, pet owner etc.). You send in a sample as well as a lifestyle questionnaire and they send you back a list of the bacterial community in your gut and how it compares to other incoming samples. I thought this was an interesting way to gain more widespread samples of the microbial gut for scientists while involving the public and raising awareness about the diversity and importance of microbes.

    http://humanfoodproject.com/americangut/
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      May 1 2013: This is the best thing ever. If they could crowd source it or something and do the sampling for free by mail I bet it would be extremely popular and would glean a lot of cool information about the biodiversity and person to person differences of human microbe ecosystems! I for one would love to know what lives in my mouth and intestines but the $99 price tag is kinda prohibitive. It's all about priorities I guess. I'm tempted to do it.
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    Apr 30 2013: You said "Do you think that a concoction of the “right” microbial species in the form of a lotion, drink, or inhalant (aka "Bacteri-ell") could be a future replacement for natural exposure to beneficial microbes?" and I find that this sort of a product would be impossible. I say this because our bodily immune systems are built little by little, not i huge strides. Pushing that many bacteria into your body at once will not help your immune system, it will devastate it, even if they are mostly beneficial microbes.

    A better question would be: Could there be a series of drinks in which a person is exposed to all the bacteria that could strengthen the bodies natural processes and it immune system?
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      May 1 2013: That is a great point, Clinton. Our immune system is something we develop slowly over time. Slow exposure to different microbes, whether pathogenic or not, allow our bodies to properly function and build up necessary immunities we need to survive. Even though biomedical technology is currently doing amazing things and new, unimaginable medicines are being created, I don't think there would be a way to subject the body to a "bacteria-elle" without doing serious damage to the overall immune system. The immune system cannot be built up instantaneously, and it could be very dangerous, even life threatening, to expose the body to an exorbitant number of (possibly foreign) microbes at one time.
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      May 1 2013: I liked this idea as well and thought that a variety of drinks could be interesting new way to shape our microbial community for the type of life style we want to live. But in reality I do not think anything will ever be as unanimously effective as nature can be on developing this community
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        May 1 2013: The point isn't to replace natures role, the point is to fill in a role nature should play, but can't. Not everyone has the time to take their kids hiking and camping that often, so this would be able to counteract the effects of not being able to.
  • Apr 30 2013: I think this is quite a brilliant idea, however I would change a few things. Instead of having 1 general kind of "Bacteri-ell" maybe there are multiple kinds, one general kind can have microbes that have been proven to have positive effects, with a cocktail of microbes that can vary based off the specific kind and what the desired affects are, for example the bliss microbe mentioned by Jessica green in her TED talk on bioinformed design. (http://www.ted.com/talks/jessica_green_good_germs_make_healthy_buildings.html).

    As well an answer to the original question of strengthening the immune system, this could be done by applying a different kind that could have trace amounts of microbes that are detrimental and are required to build a strong immune system, those being ideal for children as discussed by so many previously in this conversation.

    Although there may be probiotics in existence that do what I have discussed I feel as if in time as we grasp a better understanding of microbial diversity, alongside new methods of analyzing the human micro-biome, that we will have options like this "Bacteri-ell" as opposed to needing to receive the resistance first hand.
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      Mario R

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      Apr 30 2013: This seems like a really cool idea Benjamin! It only makes sense that our bodies would have a carrying capacity for microbes though. One questions that I can think of, what happens if the microbes start to become so abundant that they start to compete for the available resources that our bodies offer? Would this lead to a decrease in certain microbe species, and an increase in other microbe species as they do compete for? Maybe that would be the point of making multiple concoctions of microbes? This way they may be less likely to start competing with each other, or if one species does out compete another, the out competed species could be reintroduced with a different "Bacteri-ell" concoction.
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        Apr 30 2013: That's a really good point... It is really difficult for us to predict how our current microbiomes would respond to regular probiotic exposure! I'm not even sure how we would go about studying that kind of interaction... in vitro research could never replicate the complexity of a complete, functioning microbiome, and there is so much diversity (beta diversity??) amongst people, let alone between species, that the applicability of animal models would be questionable.
      • Apr 30 2013: That's a great point. I feel as of we would need a lot more research dedicated to the microbial diversity of humans, and to test the products unfortunately the only thing I would suggest would be testing the products on a closely related species. Maybe chimps, however that raises the question of does genetic or phylogenetic similarities correlate to microbial similarities.
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      Apr 30 2013: I mentioned this to someone else, but I was also wondering about the necessity of different kinds of "Bacteri-ell" Maybe "Bacteri-ell" would have to be tailored to the individual (maybe his and hers? haha.) However, maybe there is an ideal universal combination for our "microbe cloud." Obviously, we aren't very close to having this knowledge at this time. Thanks for bringing up this point!
      • Apr 30 2013: No thank you for this idea! Haha, yes we have much to learn about microbial diversity especially in relation to our personal biome.
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    May 1 2013: While it is disturbing that microbes are so under appreciated in globalized society, it is heartening to see microbiology reversing that trend. Given the historical aversion to germs and the strong cultural association that we have with things we can't see and sickness, I am happy to see more research into positive aspects of microbes.
    As far as a product to help ensure a healthy microbiome on our bodies, I would be concerned about the leaving curve of the product. An earlier comment mentions Johnathon Eisner's talk on microbiomes in which he attributes his development of type-1 diabetes to having a compromised microbiome. He also notes how the human microbiome influences our health and resiliency in other ways. With that in mind, my concern is that by developing a creme or lotion for promote microbe growth, we could disrupt peoples' microbiomes further. Just as early ecology (think introduced species) has had disastrous effects, I think adding a bunch of new microbes to a complex ecosystem could potentially do more harm than good (in some cases, anyway). So, while the idea of appreciation one's microbiome as another organ of our body (I think Eisner said that in his talk, too) is a really important step to take, I don't think that means that we should necessary slather ourselves in bacteria lotion without first better understanding how our microbiome works, and what it needs to be healthy. Is more bacteria always better? How can we nourish the microbiome we already have?
  • May 1 2013: I think in cetain level of future bacteri-ell help to strengthen or rebuild human micro biome, but the replacement may not happen. Because a significant level of microbes are encoded by the individual human DNA and there are some deviation among individual human being. It means my micro-biome is not same as yours. Then, if someone introduce a "generic bacteri-ell" to a individual, it may cause to destory his or her own micro-biome which would be worse than weaken biome.
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      May 1 2013: This has been my biggest problem with this bacteri-ell. By bring in a generic singular bacteria we aren't doing that much, since we would only be adding a single microbe like kimboucha. This isn't enough to establish a healthy microbiome. First off i don't know how this one bacteria would be able to out compete the established community of 1000s of bacteria. Then even if we did establish a bacteria, why is this the best bacteria? It could actually be causing problems with some people microbiomes. You would need a variety of different bacteria for establishing in different gut environments based on what the normal diet of the person is. This is the most logical way to create universal microbes that could help establish healthy communities.
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    May 1 2013: I think that if our society ever decides that exposure to microbes is a good thing most people would simply stop using sanitizer on certain things or try to run into particular microbes "naturally". I can totally see, however, a new health trend to be ingesting certain microbes in a very expensive bottle.
    We already encourage pro-biotic ingestion of things like kombucha and yogurt that are marketed as being full of different strains of things that are good for you.
    However popular culture still rails against the idea of not washing everything. In one episode of "The Office" Dwight is laughed at for this propensity for people sneezing on him to "increase his resistance".
    There are examples of relatively famous people actually believing in exposure to germs creating resistance. One example is Yvon Chouinard (He started Black Diamond Gear and owns of Patagonia clothing company . In an interview he says he used to encourage his kids to not wash their hands after playing outside, yet nobody is calling him crazy due to his success in life. Perhaps one day all of society will feel the same way he does, but I have a feeling it is going to take a long time before anything like that happens.
  • May 1 2013: I think the idea of "Bacteri-ell" is interesting, but I'm not sure how it would pan out. Although it is possible true that we have been over-cleansing our bacterial make up of each of our micro-biomes, they have also been discussing that each individual's micro-biome is unique to them. That means that all of the bacteria that is floating on the surface of my skin, although may consist of the similar kinds of bacteria, is in fact unique to me, just like my genetic make up. As a result, I find it hard to imagine them finding a way to mass produce a product which interacts with everyone's bacterial make up in the same way. Although it could be possible - they have found that people who are dog owners often share nearly identical bacterial micro-biomes. (http://www.npr.org/blogs/health/2013/04/18/177746969/bacteria-on-dog-lovers-skin-reveal-their-affection?utm_source=NPR&utm_medium=facebook&utm_campaign=20130418) Not only that, but "Bacteri-ell" must function similarly to natural exposure, with all the good bacteria that we want, almost like a screening effect. I find it hard to see how we can mass produce a product that can imitate the manner in which the natural world interacts with our micro-biome.
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    Apr 30 2013: I read one article that suggested increased allergies also stem from the fact that families are becoming smaller and smaller, and thus children are exposed to less bacteria to which siblings would normally expose them. I happen to be an only child, along with three of my best friends, and we all have terrible allergies compared to any of our other friends who have multiple siblings. On top of this, hyper-sanitized homes and bodies prevent the body’s immune system from strengthening at an early age. It is easy to make the analogy to weight lifting—your body won’t become stronger unless you expose it to some resistance. However, it is important to consider that people’s bodies might react to different microbes differently. A community of microbes that might help one person’s immune system might cause harm to another’s. The idea of a product containing microbes meant to help expose people and strengthen their immune system is very interesting and has great potential for the future. It may just take some trial and error to determine which microbes would universally benefit its consumers without major side effects. Also, it may be important to note that such a product may not benefit older age groups whose bodies did not become used to microbe exposure at an early age.

    http://www.sciencedaily.com/releases/2007/09/070905174501.htm
    http://www.mayoclinic.com/health/hygiene-hypothesis/an02114
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    Apr 30 2013: To add another personal anecdote, I do not have allergies of any kind and I am a huge fan of Purell. I, too, am rarely ever ill. I'm not sure if I was a particularly "germy," dirty kid but I did spend a lot of time around animals. Of course, personal anecdotes dont necessarily represent the norm, but still one has to wonder.

    Honey is absolutely amazing in terms of it's healing powers. I volunteer at a marine mammal hospital and we use honey to treat shark bite wounds on the seals and sea lions by spreading it over the wounds. I have personally seen several cases where absolutely massive injuries almost disappear within a week. We use it because it is cheap, but maybe hospitals should start using honey instead of powerful antibiotics? I don't know much about how honey ranks with traditional antibiotics in terms of microbe killing power, but maybe it works so well because it leaves some good microbes left?

    I think its important to remember that while antibacterials can do harm, but they can also do incredible healing.
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      Apr 30 2013: A particular powerful aspect of using honey is that it can used to abed the allergies that are often associated with over sterilization. There is a catch though, the honey needs come from local bees so that it is produced with local pollen. Consuming the honey builds the immune response so that allergies aren't so severe!
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      May 1 2013: I work in a deli and have at least five pretty bad burns from various HOT things I clean at my job. I apply honey immediately after getting burned and virtually receive no visible scar. I'm not sure why this is, but I agree with you about honey. It's amazing!
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    Apr 30 2013: Our bodies are teaming with microbes and from the research that we now know each of us seem to have our own set of microbes covering every inch of our bodies. Culture, community and genetics may all affect the different microbes that support our bodies. Every human has been living in a symbiotic relationship their entire lives, but no one knows it due to the fact that microbes are microscopic. Advertisements and media portray most microbes as pathogens that can cause serious illnesses. When in reality they are the key to life, as we know it. Our society over uses antibacterial cleaners but as fascinating as an idea as “Bacteri-ell” sounds I would hope that it is only used for specific medical needs. The thought that people would have to wake up in the morning to apply microbes to increase there immune system would be a horrifying. Enjoying the world around us and increasing our immune system naturally seems like the best cure.
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    Apr 30 2013: Going back to a point that was brought up a couple of hours ago--that industrialized countries need more interaction with nature to acquire these microbes-- I totally agree! The hygiene and early immune challenge hypotheses could be joined with a myriad of others acting as metaphors for how far removed much of Western civilization is from the natural world.

    To me, this is less an issue of discovering, making, and selling a bacterial concoction that humans currently lack. This is not addressing the root issue, and pushing us further away from it if anything. The root issue is that many of us never spend real time in a forest, around animals, wild plants, or most importantly, any of their microbes! Reconnecting with the microbes many of us currently lack could be solved through a reconnection with the natural world, which many of us also lack. This would not only make us healthier individuals in the sense of microbes, but also through the many other ways that nature has been proven to make us happier people.
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    Apr 30 2013: In our haste to tout antibacterial products, let's not forget the amazing benefits sanitization provides us as well! Do we really want a world where surgeons don't have to sterilize their hands or run their instruments through an autoclave before performing an operation? Where sushi chefs are free to touch as they please? Joseph Lister, Ignaz Semmelwies, and Lupe Hernandez performed a great service to society with the inventions of antiseptic and antibacterial hand washes.

    I question the argument that overuse of antibacterials causes a rise in allergies. For one thing, antibiotic agents have been around for a very long time. Honey is a natural and very effective antimicrobial that humans have been in contact for at least 8,000 years and was used by the Ancient Egyptians as an embalming agent.

    Furthermore, there is a big question of correlation vs. causality. It could be that our overly sterile lifestyle is causing an influx of allergies, or it could simply be that globalization and market integration have allowed people access to foods that they have not eaten before and thus discover new allergies. Food allergies are also very affected by ancestry. Lactose intolerance (or 'tolerance' as my high school bio teacher liked to say) evolved from a rare mutation that allowed humans to digest mammalian milk. Humans are the only mammals that consume another mammals milk as adults, and the majority of the worlds population is naturally lactose intolerant. Due to this one genetic mutation, a portion of the population can digest lactose. Lactose 'tolerance' has a distinct clinal distribution (geographic pattern) that shows the evolution of this gene occurred in Europe and North America, coincidentally the regions more recently inhabited by humans, and not in Africa and Asia where the earliest human populations came from. Approaching from a more anthropological perspective, we see there may be a simpler explanation for food allergy prevalence.
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    Eun Min

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    Apr 30 2013: Microbes were thought to be bad and dirty, pathogen. Although we have found that many microbes are good and necessary for the whole ecosystem, not only for human, some people still think microbes are pathogen; it reminds me of a rotten apple in a barrel. I do not know that not exposure to certain microbes causes or increase allergy levels, which might be related.
    As Jonathan Eisen said in the video that probiotic, poo-tea and fecal transplant, microbes are used to treat unhealthy animal. I guess bacteri-ell might come out the market soon or similar one; it is good way to get good microbes! Maybe we can buy a can of good microbes; we can sort microbes, which are necessary and help our health, and culture them and put in a can although culturing microbes are hard! Then, we can put the microbes directly on our body or put on a bed to last longer, growing them on your own bed!
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      Apr 30 2013: Thanks for pointing out the practicality of "Bacteri-ell"! One of the problems I thought of is exactly what you pointed out: microbes are hard to culture! We already have trouble with creating cultures of bacteria, would we really be able to maintain them in "Bacteri-ell?" Can you think of yet another method we could use to expose people to helpful microbes (besides poo-tee and fecal transplant...)? I was thinking that another possible medium could be animals. Maybe petting zoos with animals that definitely have helpful microbes on them (e.g. frogs!) that people could take their children to. :)
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        Apr 30 2013: Animals can do that too, but I worry about the stress what animals get and safety issue. I guess we can select an individual who is healthy and test what kind of microbes the healthy person has by collecting microbes from the person and sequencing the microbes if there is a pathogen. If not, we can let the person wear a shirt for a day and take the shirt from the healthy person and put it on a sick person, transferring microbes naturally. It sounds disgusting, but we can try?
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      Apr 30 2013: I definitely agree. It's not a matter of eliminating microbes but selecting for the beneficial ones to our health and eliminating the detrimental ones. How we select between these two still needs development however, could revolutionize our buildings and the possibility of integrating microbes environments to the surface of everyday objects.
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    Apr 29 2013: These are both good points. There is also the factor of people being overprescribed antibiotics. After time the antibiotics no longer are effective on that individual because the bacteria have become immune to it. Or there are completely resistant strains of bacteria, like MRSA for example, which is a strain of staph bacteria that has become resistant to all antibiotics that normally treat staph infections. Maybe the solution should not be to come up with a concoction of good bacteria to replace what we have already killed, but instead stop over-using antibiotics and teach people to realize that cleaner does not always mean better.
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      Apr 29 2013: I think I agree with some of your points here. People can easily over-use antibiotics and their bodies can become immune to even the good bacteria. Like you said above, too much of a good thing can be a bad thing, and this goes with cleanliness as well. We can over clean our own bodies and take away needed species of microbes from our skin. I think probiotics will become a bigger part of the industrial world that Anna is referring to. Being able to take living microbes back into our systems is one way to undo the damage of over-using antibiotics. Also just bringing into our industrial world pieces of nature like live plants can make a huge difference as well. Sometimes just opening the windows in an office can be enough to diversify the indoor microbes with some new species.
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      Apr 30 2013: Breena: The good bacteria is not really supposed to replace what has already been killed, but rather as a means to expose people to microbes that they haven't even encountered yet. I agree that the use of antibiotics, especially in children, needs to be investigated further in order to prevent adverse effects.

      Marissa: I like your point about bringing more nature into industrial regions. There was a TED conversation you might be interested in (link below) where a guy suggested that cities should have "controlled" muddy playground for children. The idea is that these playgrounds would allow youths to be exposed to good microbes, as they are on farms. http://www.ted.com/conversations/12518/should_cities_create_dirty_mud.html
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        Apr 30 2013: That makes sense. Sometimes I am just like, "if this wasn't around in the world everything would be great, so lets get rid of it!" Which doesn't actually work in the real world. I looked at the TED talk you recommended for Marissa, very interesting. I was reading someone's idea about creating technology that can have a symbiotic relationship with specific microbes. What do you think of that idea?
      • May 1 2013: Anna, does this remind you of the "pox parties" kids had/have growing up where every parent flocked to the first child that got chicken pox so that they could get it out of their children's systems? I'm not sure if that was a thing when you guys were young, but it was when I was. Wouldn't it be a funny sight to see all of the "urban" kids sent to the farm while their immune systems were still pretty plastic so that they could potentially be exposed to good microbes!?

        (P.S. most doctors don't recommend "pox parties")
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          May 1 2013: Now that you mention it, I totally remember that! Parents definitely used to be on the look out for the first chance to expose their child to someone else with chicken pox. Hopefully urban kids do get a chance to visit farms, for various reasons.

          Thanks for bringing up pox parties. I had totally forgotten about that; pretty amusing.
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    Apr 29 2013: I think it’s important to get microbes from nature into our houses and into us. The bacteria we are exposed to right when we are born sets up our bacterial species composition that persists and evolves throughout the years. What effect this has on human health is still poorly understood. There are however studies which show that bacterial compositions do have some effects on health. For instance, it has been shown that obese people have a different gut bacterial compositions than those who are not. In one study, rats that were genetically predisposed to obesity, when given fecal transplants from rats that were not overweight, lost their excess weight and kept it off. Studies like this one have been cited to encourage the ingestion of probiotics, however, it’s still unclear if these (after passing through the acidic conditions of the stomach) are effective at colonizing the already colonized human gut.

    In many industrialized nations, various food items are irradiated, which goes a long way towards preventing foodborne pathogens but also kills good bacteria as well, so we are likely not getting exposed to the amounts and types of bacteria we evolved with. I do see a future when we will be lathering up with and ingesting more bacteria but until then, I’d say were better off safe than sorry and not going overboard with cleanliness (unless we know we’ve been exposed to pathogens) and making sure we get enough outings in nature wouldn’t hurt.
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      Apr 30 2013: In reference to gut bacteria, the food we ingest has an effect on the bacteria in it as the bacteria do on us. Essentially, we eat food and take what we can/need from it, then the bacteria digest the majority of what we don't.
      For instance, if a lactose intolerant person (lacking the ability to produce lactase, the enzyme that breaks down lactose, a sugar in dairy products) drinks milk or eats a slice of cheese, they don't digest it, but the microbes in their gut do. The digestion of lactose by gut bacteria then causes excess gas and abdominal cramps. What they ate directly affected the activity of those microbes. In contrast, when we eat foods that are lower in fiber our cholesterol levels rise.
      Fiber has a two fold effect on our health. First, it swells in our large intestine and works like a scrubbing pad on its walls. Second, it feeds the majority of good bacteria that reside in out gut. Both of these effects work in unison to maintain lower LDL cholesterol and promote a healthy cardiovascular system as well as a healthy digestive system.
      My point is, there are almost always natural ways of changing the biodiversity of our personal microbiome and we should take advantage of them.
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        Apr 30 2013: I definitely agree with you about finding the more natural ways of accruing the biodiversity of microbes that we need. Why try and use synthetic ways when a natural way is there?
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      Apr 30 2013: I think it is really interesting that there are differences in gut microbes between obese people and those who are not. Do you think this is genetically linked or do obese people house these microbes because of their lifestyle? I also agree that taking the natural way to help change our personal microbiome may be a better solution than possibly introducing a "baceri-ell" that could then cause more problems since we know so little about microbes.
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        Apr 30 2013: I think the mice in the study I mentioned were reared the same way, so same diet and everything but the experimental group was genetically predisposed to obesity. I tried looking for the paper but couldn't find it. Here's an interesting article that mentions a similar study though: http://blogs.scientificamerican.com/brainwaves/2012/09/12/the-food-fight-in-your-guts-why-bacteria-will-change-the-way-you-think-about-calories/
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          May 1 2013: I also have read a study of sterile mice vs normal mice and the effects that microbes have on body weight. The sterile mice were fed autoclaved food while the normal mice received non-sterilized food. The mice without microbes were significantly obese and nutrient-deficient. With all the sterile food products in today's world, no wonder we see problems in diet and an increase in problems linked to our microbiomes. When sterile mice were inoculated with gut flora from the non-sterile mice, a decrease in body fat was seen and the mice were indeed healthier.

          Looking back in history we see a trend of preserving food by the addition of bacteria and other cultures. There are so many beneficial microbes used in food processing including: beer, wine, bread, yogurt, cheese, keifer, and kombucha. These cultures have been an integral part of the human gut flora and have benefited humans for centuries. Not to mention the digestion of the probiotic cultures themselves is extremely nourishing for your body.

          For instance, when I was young my mom gave us kombucha (this took away heartburn and stomach aches almost instantly). My mom said it was a Chinese mushroom, but actually it is a biotic mat of anaerobic and aerobic bacteria. Our family has cultured this probiotic for years and the diversity of the different scobies is astounding. Depending on what kind of scoby you aquire does make a difference in the flavor and properties of your kombucha. Most people think of probiotics as just yogurt or acidophilus, but really humans have been using them for years to survive and treat medical issues. Why throw this method out with the bathwater? We should listen to our history, not fight against it.
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        May 1 2013: Everything in your gut microbiota is influenced by lifestyles that you engage in after birth. Originally for the environment of the gut, it is sterile and must be colonized. This is why as soon as you first feed the baby it starts to gain some microbes, and as he continues to process more food, more microbes begin to colonize this new environment. This is why as you raise your child, deciding what you feed them causes massive shifts in how their gut microbiota will form
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          May 1 2013: Also, it is interesting to observed the differences in mothers who breastfeed their children vs ones that give them formula. Children fed formula do not receive the beneficial enzymes and microbes in breast milk often develop serious allergies and colic. There are some probiotics in formula, but I still don't think they are better than nature's version. I agree with everyone in saying, maybe nature is just the best answer.
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    May 1 2013: Hi Anna,
    I think part of the reason for increased allergy levels and increased cancer, is that our environment is becoming more toxic, which compromises our immune systems.
  • May 1 2013: If a silver-bullet bacteri-ell was hypothetically produced, do you think drug and body care companies would simply not fund the product? Would the risk it would pose for loss of profits, considering a silver-bullet bacteri-ell would solve many many health issues and negating the need for many more products, be too big?
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    May 1 2013: I almost feel like there's no point in creating a product like "bacteri-ell" to replace purell in our society. It seems like it would be a silly thing that people wouldn't want to use, because since their polar opposites, they serve entirely different functions. People use Purell to keep themselves from coming in contact with other people's illnesses or to get ready to eat or just for general hygiene, and a lot of these things that things that bacteri-ell wouldn't help prevent. I do understand that it makes sense to have a higher level of exposure to microbes that can help with immune response and such things, but I think this should be accomplished in a more natural way, by such things as letting kids play outside and interact with other people at a young age, so they can be naturally exposed to a range of microbes while they're still young enough to combat anything harmful they may come in contact with. I know that as a child I was allowed to do these things and I have a very healthy immune system. I very rarely get sick and I don't have any allergies because I think I was exposed to these things enough in my daily life as a child that they're already incorporated into my body. I don't think a product like bacteri-ell would be necessary, really.
    • May 1 2013: I agree with Melissa. There are definitely services antibacterials provide that keep plenty of us healthy everyday. Purell prevents the spreading of viruses, and I use it regularly throughout the winter to prevent sickness during exam time. Exposure to the right bacteria should happen early, as Melissa said, and regular outdoor activity should theoretically be enough to maintain the microbes, as well as introduce new ones, on and in the human body.
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        May 1 2013: Yeah, I definitely think that a natural exposure is the way to go. That's how many cultures and how people historically gained exposure to bacteria and it's worked this long, so why change it? While medical advances have been great and something like a bacteria lotion seems convenient, it seems like something along that line could go terribly wrong, as it takes out the necessity for outdoor exposure. I feel as though it would be less effective to be introduced to airborne allergens and microbes through the air, rather than through our skin, as that it not the main way we have exposure to these things in the real world, so our resistance may not be as effective or strong.