Category Archives: Hygiene Hypothesis

Antidepressant Bacteria in Soil – Boosts Serotonin








Nature provides! There’s a bacterium living naturally and ubiquitously in the soil that we’re likely to ingest or inhale when we spend time outdoors in natural environments: Mycobacterium vaccae – also called  The Golden Bacillus. You can see why it’s called that:


Mycobacterium vaccae

Mycobacterium vaccae (Source:


 Beautiful, isn’t it?
This bacterium is highly beneficial. It boosts our serotonin levels, reduces anxiety and makes us feel happier.
Golden Bacillus, Mycobacterium vaccae, has been shown to act like a natural Prozac (without the bad side effects). Like Prozac, it apparently stimulates serotonic production, making you feel more relaxed, less stressed, and generally happier.
In studies, when the bacterium was given to cancer patients, they reported feeling less stressed and experiencing a better quality of life. (Grant, 2014) (Hemmingway, 2015)






In  a lab rat study,  Mycobacterium vaccae received by injection and via feeding led to improvement in the animals’ cognitive ability, increased concentration when performing tasks, and lowered stress level compared to a control group that didn’t receive the soil bacteria. And the effects were seen for up to three weeks. (Grant, 2014).











(Cann, 2015) (McIntosh, 2015) (Wikipedia, 2015A)


The Serotonin Molecule



Serotinin is an important chemical manufactured by our bodies that acts as a neorotransmitter, enabling brain and other nervous system cells to communicate with each other – though some prefer to regard serotonin as a hormone. The vast majority of the body’s serotonin, 80-90%, is produced in the GI tract’s intestinal mucosa (by enterochromaffin cells). The small amount made in our brains cannot cross the blood-brain barrier so must be produced there.
Serotonin plays many essential roles in the body, affecting:
  • Mood and social behavior
  • Appetite and digestion
  • Bone metabolism
  • Breast milk production
  • Liver regeneration
  • Cell division
  • Intestinal movements
  • Sleep
  • Memory and learning
  • Sexual desire and function










If your body produces too little or too much serotonin, you’re likely to experience all kinds of common gut issues: Too little serotonin and you’re likely to feel depressed and anxious – and be constipated. Too much and you’re likely to feel nervous and nauseated – and have diarrhea.

Too Low Serotonin Level






Symptoms of low serotonin levels include (Boeree, 2009)  (Wilson, 2015):
  • Depression
  • Insomnia
  • Anxiety
  • Negative thinking
  • Problems with anger control
  • Obsessive-compulsive Disorder
  • Suicidal thought and behaviors
  • Craving carbohydrates (starchy foods)
  • Obesity
  • Fibromyalgia pain
  • Migraine headaches
  • Irritable Bowel Syndrome (IBS)





Too High Serotonin Level

Having too much serotonin, can lead to excessive nerve cell activity, a state called Serotonin Syndrome, that often begins within hours of taking a new medication that affects serotonin levels or from greatly increasing the dose of one you’ve been taking. Symptoms include (WebMD, 2015A):
  • Confusion
  • Agitation or restlessness
  • Dilated pupils
  • Headache
  • Changes in blood pressure and/or temperature
  • Nausea and/or vomiting
  • Diarrhea
  • Rapid heart rate
  • Tremor
  • Loss of muscle coordination or twitching muscles
  • Shivering and goose bumps
  • Heavy sweating
In severe cases, taking too much serotonin can be life-threatening. If you have these symptoms of Serotonin Syndrome, get medical attention promptly:
  • High fever
  • Seizures
  • Irregular heartbeat
  • Unconsciousness








(Naish, 2013)




Prozac (fluoxetine) is a selective serotonin re-uptake inhibitor (SSRI) pharmaceutical widely used for treating major depression and depressive disorder, OCD, premenstrual syndrome, panic disorder, and bulimia. It was first developed and marketed by Eli Lilly in 1988 and was an instant hit … as the “Happy Pill”. 27 years later, more than 20% of Americans (children, adults, the elderly) regularly take mood-altering drugs prescribed by their doctors. Even anxious dogs are put on Prozac.
Scientists at Eli Lilly first found that fluoxetine reduced hypertension in some animals but were disappointed when it didn’t have this same effect when tested on human subjects. Then the company thought the chemical could be marketed as an anti-obesity pill but again their clinical trials failed. When they tried it out on five volunteers who had mild depression, the subjects felt much better. Eureka!, they’d discovered a gold mine of profits. Fluoxetine apparently had the ability to improve mood.
Fluoxetine was rebranded as an anti-depressant by marketing experts and sold as Prozac. The two-syllable name combined something positive sounding (pro) with something zippy sounding (zac). Doctors now had a one-pill fix for all those people in their practices suffering from depression and its accompanying variety of pesky symptoms. These people could now be zapped into positivity. Prozac’s great success then led to a spate of other SSRI anti-depressant drugs – including Aropax, Celexa, Cipralex, Cipramil, Lexamil, Lexapro, Luvox, Paxil, Seroplex, Viibryd, and Zoloft.
What a great boon for humanity.
Well, perhaps not.




The following side effects are associated with Prozac (WebMD, 2015B):

Common side effects of Prozac:

  • Anxious
  • Chronic Trouble Sleeping
  • Diarrhea
  • Dizzy
  • Drowsiness
  • Dry Mouth
  • Excessive Sweating
  • Feel Like Throwing Up
  • Feeling Weak
  • Head Pain
  • Indigestion
  • Involuntary Quivering
  • Loss of Appetite
  • Nervous
  • Rash
  • Sinus Irritation and Congestion
  • Throat Irritation
  • Yawning

Infrequent side effects of Prozac:

  • Chills
  • Hives
  • Trouble Breathing
  • Abnormal Dreams
  • Abnormal Heart Rhythm
  • Altered Interest in Having Sexual Intercourse
  • Chest Pain
  • Confused
  • Cough
  • Excessive Thirst
  • Fast Heartbeat
  • Feeling Restless
  • Fever
  • Flu-Like Symptoms
  • Frequent Urination
  • Gas
  • Hair Loss
  • Heart Throbbing or Pounding
  • Hyperactive Behavior
  • Inability to have an Erection
  • Incomplete or Infrequent Bowel Movements
  • Itching
  • Joint Pain
  • Problem with Ejaculation
  • Problems with Eyesight
  • Ringing in the Ears
  • Sexual Problems
  • Stomach Cramps
  • Taste Problems
  • Weight Loss
  • Widening of Blood Vessels

Rare side effects of Prozac:

  • A Spasm of the Larynx
  • Abnormal Liver Function Tests
  • Allergic Reaction causing Serum Sickness
  • Angle-Closure Glaucoma caused by Another Disease
  • Behaving with Excessive Cheerfulness and Activity
  • Bleeding of the Stomach or Intestines
  • Bronchospasm
  • Erythema Multiforme
  • Giant Hives
  • Having Thoughts of Suicide
  • Hepatitis caused by Drugs
  • Increased Risk of Bleeding
  • Inflammation of Skin caused by an Allergy
  • Life Threatening Allergic Reaction
  • Low Amount of Sodium in the Blood
  • Mild Degree of Mania
  • Neuroleptic Malignant Syndrome
  • Prolonged Q-T Interval on EKG
  • Reaction due to an Allergy
  • Seizures
  • Serotonin Syndrome – Adverse Drug Interaction
  • Stomach or Intestinal Ulcer
  • Swollen Lymph Nodes
  • Throwing Up
  • Very Rapid Heartbeat – Torsades de Pointes
  • Abnormal Bleeding from the Uterus
  • Abnormally Low Blood Pressure
  • Difficult or Painful Urination
  • Dilated Pupils
  • Grinding of the Teeth
  • Loss of Memory
  • Loss of One’s Own Sense of Reality or Identity
  • Low Blood Sugar
  • Mood Changes
  • Sun-Sensitive Skin
  • Uncoordinated


Serious birth defects are also associated with a woman’s taking Prozac during pregnancy, especially during the last four and a half months. (DrugWatch, 2014)









So maybe you’re anxious or depressed and prefer avoiding the side effects of pharmaceuticals. In my psychotherapy practice over the years, I’ve noticed that people on long term anti-anxiety/anti-depressant drugs are often separated from their feelings. They may not feel very depressed or anxious but they also don’t have easy access to who they are or how they actually feel – ie, they tend to make decisions based on their thoughts rather than with their vital gut feelings.
Maybe this doesn’t appeal to you.





We already know that the health of the microflora living in our intestines is directly connected to the overall health of our bodies – including mood.  And remember that the vast majority (80-90%) of the serotonin (our natural feel-good chemical)  in our bodies is produced inside our intestines, in the gut’s mucosal layer – which is also, not coincidentally, where the bacteria and other micro-organisms that make up our gut microbiome live. So it’s not the least surprising that a bacterium found in soil would have anti-depressant qualities.


Mycobacterium vaccae (The Golden Bacillus)







Scientists are looking into whether exposure to mycrobacterium antidepressant microbes in soil can improve Crohn’s disease and rheumatoid arthritis (both are autoimmune conditions stemming from chronic inflammation caused by an unbalanced gut microbiome), as well as cognitive functioning. (Grant, 2014)
Research is also underway to see if a killed Mycobacterium vaccae vaccine can be effective in the treatment of asthma, cancer, leprosy, psoriasis, dermatitis, eczema, and tuberculosis. (Wikipedia, 2015B)













(Source: )




I highly recommend taking a look at Michael Polan’s excellent New York Times article “Some of My Best Friends Are Germs“. He discusses the importance of our gut bacteria, how our modern obsession with finding and killing all germs is making us ill (The Hygiene Hypothesis), the fact that children who are exposed to dirt have healthier immune systems, and lots of other fascinating information.
This is a photo from the article:



(Source: Image Credit: Credit Hannah Whitaker for The New York Times)
Image Credit: Hannah Whitaker for The New York Times)







The presence of Mycobacterium vaccae, the Golden Bacillus, in dirt gives us yet another compelling reason to do something to stop the great rate at which we’re depleting the soil’s microbiome with GMO crops, herbicides, and other toxins.  Healthy soil presumably contains more Mycobacterium vaccaeis than depleted soil. If humans continue destroying the earth’s resources, we may succeed in killing off the beautiful Golden Bacillus.
How depressing.








Boeree, E.G. (2009). Neurotransmitters. See:

Cann, K. (2015). Low Serotonin and Gastrointestinal Disorders. See: (2014). Prozac. See:

Grant, B. L. (2014). Antidepressant Microbes In Soil: How Dirt Makes You Happy. See:

Hemmingway, W. (2015). Happy Dirt: A Microbe Found In Soil Mimics Prozac. See:

McIntosh, J. (2015). What is serotonin? What does serotonin do? Medical News Today. See:

Naish, J. (2013). The Jekyll and Hyde happy pill: It’s brought relief to millions but is linked to suicide, low libido and birth defects, and we still don’t know how Prozac works. See:

Polan, M. (2013). Some of My Best Friends Are Germs. New York Times Magazine, May 15 2013. See:

WebMD. (2015A). What Is Serotonin Syndrome? See:

WebMD. (2015B). Prozac: Side Effects. See:

Wikipedia. (2015A). Serotonin. See:

Wikipedia. (2015B). Mycobacterium vaccae. See:

Wilson, J. (2015). Low Serotonin Levels Symptoms. See:

© Copyright 2015 Joan Rothchild Hardin. All Rights Reserved.


DISCLAIMER:  Nothing on this site or blog is intended to provide medical advice, diagnosis or treatment.

How Hand Sanitizers Are Bad for You and the Planet





I’ve written on the dangers of hand sanitizers here and there on this site but decided to devote a whole post to them after encountering a big wall dispenser of Purell above a sink in a lovely West Village church bathroom  yesterday – with no hand soap option. I’m sure the church believes they  made a sensible choice. This got me thinking about how thoughtful people have been seriously misled. So here’s the explanation of why Purell in a bathroom is a bad idea.



It’s important to understand how the heavy use of Purell and other hand sanitizers is doing harm to our health.
The prevalent obsession with germs, viewing all of them as harmful and in need of being killed, is based in ignorance and simply misguided. Without the billions of friendly micro-organisms living in and on our bodies, we wouldn’t be able to sustain life. When we ruthlessly kill them on our skin and inside our bodies, we are doing ourselves a great disservice and jeopardizing our health.
As Michael Pollan, a well known American author, journalist, activist and professor of journalism at the UC Berkeley Graduate School of Journalism, put it in his excellent article Some of My Best Friends Are Germs (Pollan, 2013):

… as a civilization, we’ve just spent the better part of a century doing our unwitting best to wreck the human-associated microbiota with a multifronted war on bacteria and a diet notably detrimental to its well-being. Researchers now speak of an impoverished “Westernized microbiome” and ask whether the time has come to embark on a project of “restoration ecology” — not in the rain forest or on the prairie but right here at home, in the human gut.









The HYGIENE HYPOTHESIS offers an explanation of why it’s important to be exposed to a wide variety of germs in childhood:
A lack of early childhood exposure to infectious agents, symbiotic micro-organisms such as gut flora probiotics, and parasites increases susceptibility to allergic and other autoimmune diseases by suppressing the natural development of the immune system. The lack of exposure leads to defects in the establishment of immune tolerance.
The Hygiene Hypothesis is also sometimes called the Biome Depletion Theory or the Lost Friends Theory.


1932 news item from Nov, 1932: POOR KIDS MORE IMMUNE TO GERMS ... An early observation consistent with the Hygiene Hypothesis .(Source: Modern Mechanix
Canadian news item from Nov, 1932: POOR KIDS MORE IMMUNE TO GERMS … An early observation consistent with the Hygiene Hypothesis (Source: Modern Mechanix


The result of providing too sanitary an environment for our children is that they aren’t able to build up a natural resistance to pathogens, making them more susceptible to developing allergies, asthma, skin conditions and a wide variety of other illnesses and diseases – including all the autoimmune conditions, heart disease and depression. Specifically, lack of exposure to pathogens is believed to lead to defects in the establishment of immune tolerance. (Hardin, 2014)
In Some of My Best Friends Are Germs, Pollan mentions the interesting finding that children who live with a dog at home are healthier overall, have fewer infectious respiratory problems, fewer ear infections and are less likely to require antibiotics. This is strong support for the Hygiene Hypothesis. Researchers found that the effect was greater if the dog spent fewer than six hours inside – the longer dogs are outdoors, the more dirt they bring inside with them so the children are exposed to more diverse micro-organisms from playing with and being licked by their dogs. (Pollan, 2013)
Isn’t this the perfect point to make to parents who tell their children they can’t have a dog because dogs are too dirty?


Many schools in the US now require children to carry and use bottles of hand sanitizers. And, at least in the US, there are Purell dispensers all over hospitals, doctors’ offices, clinics, airports, work places, grocery stores, bathrooms – and in people’s purses and pockets.
The widespread use of hand sanitizers and antibacterial soaps is seen by many as an unwelcome epidemic harming individuals’ health and contributing to the rise of drug resistant bacteria, often referred to as super bugs. (Hardin, 12/22/2013)
For more information on the Hygiene Hypothesis and why it’s important to be exposed to diverse populations of microbes, see Live Dirty, Eat Clean … The Gut Microbiome Is the Future of Medicine.





Hand sanitizers, antibacterial soaps, toothpastes, and other products that “kill 99% of germs” likely contain triclosan. In 1969 triclosan was registered as a PESTICIDE  and is now widely used as a potent germicide in personal care products.
Do you think it’s a good idea to rub a pesticide on your skin?
As with antibiotics, triclosan doesn’t distinguish between useful microbes and pathogenic ones in destroying that 99%.  Among the harmful effects of using anything containing triclosan is evidence that it interferes with fetal development. The US Food and Drug Administration (FDA) reports evidence that triclosan disrupts the body’s endocrine system, altering hormone regulation. Bacteria exposed to triclosan are apt to become resistant to antibiotics. It weakens the heart muscle, impairing contractions and reducing heart function. It is known to weaken skeletal muscles, reducing grip strength. It washes into sewage systems and pollutes our waters. And it has been found in the blood, urine and breast milk of most people. (Hardin, 9/6/2014)
Triclosan, originally used as a pesticide, is a hormone disruptor found in thousands of products like toothpaste, cutting boards, yoga mats, hand soap, and more. (Source:
Triclosan, originally used as a pesticide, is a hormone disruptor found in thousands of products like toothpaste, cutting boards, yoga mats, hand soap, and more. (Source:


At least Purell doesn’t contain triclosan.
For more information on triclosan, see my 9/6/2014 blog post Triclosan, Your Toothpaste and Your Endocrine System.




There is strong evidence that anti-bacterial soaps and hand sanitizers containing triclosan contribute to antibiotic-resistant bacteria, often referred to as super bugs.
Ten years ago, in 2004, a research team at the University of Michigan exposed bacteria to triclosan and found increased activity in cellular pumps that the bacteria use to eliminate foreign substances. Stuart Levy of Tufts University School of Medicine, one of the study’s authors and a leading researcher on antibiotic resistance, pointed out that these overactive excretory systems “could act to pump out other antibiotics, as well.”




This is a serious problem. Pathogenic bacteria such as streptococcus, staphylococcus, and pneumonia are already in the process of evolving defenses against currently used antibiotics and pharmaceutical companies aren’t developing many new antibiotics.
In the 15 years between 1999 and 2014, the FDA approved only 15 new antibiotics – compared to 40 in the previous 15 years. The World Health Organization currently regards antibiotic resistant super bugs as “a threat to global health security”. (Butler, 2014)








And then there’s my favorite bacterium: Clostridium difficile – the one you may not have even heard of but which has reached epidemic proportions, infecting 250,000 people and causing 14,000 deaths each year in the US alone. I had a nasty C. difficile infection in 2010 and fortunately didn’t die from it – though there were times I thought I was going to and felt so miserable I sometimes wished I would.
You can read here about how I vanquished my C. difficile infection without resorting to antibiotics – the usual Western treatment for it. It just didn’t make sense to me to take more antibiotics since it was frequent antibiotics that had weakened my gut microbiota to the point that a C. diff overrun took over.
The bottom line about C. difficile and hand sanitizers is that NO TYPE OF HAND SANITIZER  KILLS IT. (Centers for Disease Control and Prevention, 2012)










Educate yourself about friendly bacteria versus pathogenic ones, return to washing your hands the old fashioned way – with soap and water, use your “hand sanitizer” only for emergencies – and teach this to your children.
If you must, use a non-triclosan-containing hand sanitizer to clean surfaces on phones, keyboard and  laptops, and other high-touch surfaces. But clean your hands with good old soap and water.


Use the soap
Use the soap





Butler, K. (2014). Does Purell Breed Superbugs? The dirty truth (and the good news) on hand hygiene. Mother Jones. See:

Centers for Disease Control and Prevention. (2012). Life-threatening germ poses threat across medical facilities. See:

Hardin, J.R. (2011). Successful Holistic Treatment of Clostridium Difficile Gut Infection: Case Study. Oriental Medicine Journal, 19:4, 24-37.  See:

Hardin, J.R. (12/22/2013). Asthma. See:

Hardin, J.R. (2011). Successful Holistic Treatment of Clostridium Difficile Gut Infection: Case Study. Oriental Medicine Journal, 19:4, 24-37.  See:

Hardin, J.R. (9/6/2014). Triclosan, Your Toothpaste and Your Endocrine System. See:

Hardin, J.R. (8/6/2014). Live Dirty, Eat Clean … The Gut Microbiome Is the Future of Medicine. See:

Polan, M. (2013). Some of My Best Friends Are Germs. New York Times Magazine, May 15 2013. See:



© Copyright 2014 Joan Rothchild Hardin. All Rights Reserved.


DISCLAIMER:  Nothing on this site or blog is intended to provide medical advice, diagnosis or treatment.