If you've ever watched a couple of episodes of Star Trek or maybe a few of the Star Wars movies, you're no doubt familiar with the alien-entity-takes-over-your-mind motif.

It could be as benign as Obi-Wan's "These aren't the droids you're looking for," or it could be more gruesome; some scaly creature with pincers crawls into your ear canal, wraps itself around the base of your spinal cord, and starts controlling your body as deftly as if you were just another Muppet with someone's arm up your ass.

But I'm here to tell you that it's happening right now in real life, that you and I and just about everybody on the poor besieged planet are already being controlled by alien entities.

Of course, calling them alien might be a misrepresentation because they've been here on planet Earth a lot longer than we have.

These alien entities are called bacteria and not only do they play a big part in regulating your digestive system and your immune system, but even your emotions and the way you think.

Think that's a stretch? Well let me throw some wild and wooly science at you.

Let's first consider the numbers:

Your body is comprised of approximately 10 trillion human cells. But you also harbor approximately 100 trillion bacterial cells. Do the math. You're 90% non-human.

There are far more bacteria in your body than there are people on earth. There are even more bacteria in your body than there are stars in the Milky Way.

Together, the bacteria in your body represent roughly 3000 species, with a collective pool of 3 million distinct genes. Compare that with the paltry 18,000 or so that make up the human body.

Are you starting to get the picture that maybe, just maybe, it's possible bacteria exert a little more influence on us than we might have thought? Even if you concede that notion, you're probably a little skeptical as to the claims I made about "mind control."

Fair enough, so let me tell you a short story.

Apparently, Natalie Wood Wasn't a Yogurt Eater

A couple of years ago, neuroscientist John Cryan of University College Cork in Ireland conducted a very weird experiment. He took mice and divided them into two groups, one of which was of course the control group. The other group was fed lactobacillus ramnosis, a bacterium often used to make generic yogurt.

After a couple of weeks, he threw them all in bowls of water to see how they'd react to water stress. Now rodents are very good swimmers, but they absolutely hate water; it freaks them out. The control group tried frantically to get out of the bowl. Their efforts continued for approximately four minutes until they became exhausted and gave up. It's what's known as "behavioral despair."

But the bacteria-fed mice? They too tried to get out, but their efforts were far less frantic. They continued swimming around the bowl past the four-minute barrier of the control group. They might as well have been enjoying a post-brunch dip at the pool at the Beverly Hills Plaza.

Finally, at six minutes, Cryan pulled the soggy rodents out, whereupon they no doubt slipped on some Tommy Hilfiger terry cloth post-swim cover-ups.

You're no doubt thinking the yogurt somehow conferred extra endurance to the test group, right? Well, you're wrong and I think you're just sucking up to the depressingly gray Jamie Lee Curtis.

Cryan found that the levels of stress hormones were 100-fold higher in the control group. All that panic isn't good. You burn out and shut down after a couple of minutes, as was the case with the mice in the control group.

The lactobacillus mice, however, had half as much stress hormone flowing through their mousy veins. Additionally, they exhibited a profound change in the distribution of their GABA receptors into a pattern associated with calm, non-depressed animals. What you need to know about GABA is that it acts pretty much the opposite of stress hormones. It makes you chill out so that when you're thrown in a bowl of water, you don't panic; you don't reach the point of behavioral despair.

The lacto mice acted as if they were on Valium, or maybe gotten hold of some really primo indica.

So how was it possible that bacteria in the mice's guts were somehow having a calming effect on the mice's' brains? What in the wide-wide world of mind control was going on?

Cryan had the same questions so he duplicated the experiment, but this time, before placing the lacto mice in the water, he severed their vagus nerve, which is the big honcho cranial nerve that meanders from the abdomen to the brain.

The lacto mice with the severed nerve acted just like the control mice! Frantic paddling. Behavioral despair. Cries of "Help me, you bastard!" Giving up at roughly four minutes. In fact, all beneficial responses were absent.

The inescapable conclusion is that somehow, a colony of lactobacillus bacteria living in the guts of the long-swimming mice had somehow chemically tweaked their Vagus nerves, sending a signal to the brain to release the calming chemical GABA.

It's wild all right and downright interesting to most science-geek types, but does it have any carryover to humans? Can bacteria actually affect the neurochemistry of humans, change the way we think and react to stress and who knows what else?

The short answer is, yeah, it looks like it.

A study similar to Cryan's mouse study was recently conducted in France, albeit with humans and the absence of any water sports. Test subjects were fed massive amounts of two probiotics, Lactobacillus and Bifidobacillus.

After a couple of weeks, standardized psychological surveys indicated that the subjects were less stressed, less anxious, and less depressed. These results were confirmed with assays of their 24-hour cortisol levels.

The theory is that the strains of bacteria produced an inordinate amount of serotonin, which is a calming chemical that often rises, for instance, after you eat high-carbohydrate foods. In truth, the human brain normally contains a very small amount of serotonin, while 80% of your serotonin supply is found in the gut, so it shouldn't be a stretch to think that bacteria aren't influencing the supply.

The results of these two experiments, along with others that have been showing similar results, has led the National Academy of Sciences to actually start wondering if they could treat psychological disorders not with drugs, but with "medicinal" yogurt.

But "mind control" is just the tip of the fermented chunk of cheese of biological processes influenced by bacteria.


You Know That We Are Living in a Bacterial World, And I am a Bacterial Boy

Just about everybody has at least an inkling of the role bacteria play in digestion, how they help break down complex carbohydrates and help retain nitrogen from the breakdown of proteins and how a lot of your poop is just dead or dying bacteria out on a wild joy ride, but I don't want to focus on that stuff.

Instead, I want to explore the less well-known attributes of these strange, too-often ignored organisms.

For instance, it's believed that the "good" bacteria, the probiotics, are involved in a constant life and death struggle with pathogens. They do this by damaging or killing these pathogens, sometimes by secreting chemicals, sometimes by changing the pH of the environment, or sometimes by just crowding them out.

These good bacteria also produce, as byproducts of their metabolism, nutrients key to our immune system like certain B vitamins and vitamin K. In fact, probiotics are thought to comprise about 70% of our immune system.

Even the appendix – once thought to be a vestigial organ – seems to be a repository of probiotics, releasing them as needed during infections.

Many diseases that plague us might simply be caused by dysbiosis, an imbalance between probiotics and pathogens. There are the obvious ones like irritable bowel syndrome (IBS) and Crohn's disease, but other, less suspect diseases like cardiovascular disease and diabetes might also be caused or exacerbated by dysbiosis.

Note: In the case of diabetes, we usually treat it with drugs to control the production of glucose, without for a minute considering that the bacteria in our gut also produce glucose. Perhaps a two-pronged attack, with enzymes targeted at both sources would have the best effect.

It's even believed that dysbiosis might be related to just about any autoimmune disease you can think of, from asthma and arthritis to ulcerative colitis and vitiligo.

There's also been a lot of research lately on the idea that bacteria might play a large part in determining body fat levels! Gastric bypass surgery, largely thought to be effective purely because of physics, i.e., a smaller stomach leads to fewer calories being ingested, but as much as 20% of the weight-loss effect may simply be from a subsequent shift of the balance of bacteria in the gut.

Mice subjected to bypass surgery lost weight, as expected, but when scientists transplanted the intestinal contents of the bypass mice to control mice, the control mice rapidly lost weight, too. The same procedure could well work with humans.

Another study involving 792 subjects found that overweight people might harbor a certain type of bacteria that may contribute to weight gain by helping other organisms in their environment digest certain nutrients, thereby making more calories available.

They theorize that this type of bacteria might have been useful to humans thousands of years ago when roughage played a much bigger role in the diet and it was essential that every possible calorie be squeezed out of the available food.

Studies on the relationship between bacteria and obesity even led to the puzzling but welcome observation that mice fed a vanilla-flavored yogurt grew substantially larger testicles, so much so that they walked with a "swagger" not unlike John Wayne's, although it's not known whether the actor's gait was merely an affectation or indeed the result of large balls.

Two groups of mice were involved, one fed a junk food diet plus yogurt, and one fed a healthy diet plus yogurt. The junk food eaters experienced a 15% increase in testicular size while the healthy eaters only experienced a 5% increase (the junk food eaters had smaller balls to begin with, hence the disparity in percentages).

The yogurt eaters also inseminated faster (I'm assuming this doesn't mean what it sounds like – that eating yogurt leads to premature ejaculation) and produced more offspring. Lastly, they also grew shiny coats and had 10 times the "follicular density" of normal, un-yogurted mice, making them look like tiny, white-haired Alec Baldwins.

Would it also apply to human types? It seems it might. Harvard nutritional epidemiologist Jorge Chavarro has found that ingesting yogurt improves the semen quality in human males.

If You Don't Like Germs, Junior, You'd Best Stay in Your Womb

The first and last time you were ever sterile – completely free of bacteria – was in the womb. But then, as you were rudely ushered out into the world through your mother's birth canal, you were simply inundated in bacteria.

Note: Babies that are delivered by Caesarean miss out on this seemingly vital bacterial bath and as a result are thought to be more susceptible to certain allergies, eczema, and even obesity.

You were then exposed to a world of microorganisms. In the subsequent weeks and months, you were handled by a bacteria laden mother and father, exposed to bacteria laden air, kissed by a bacteria laden aunt or uncle's lips, licked by a bacteria laden dog's tongue, and sucked on a bacteria laden carpet, all of which played a part in establishing your particular bacterial ecosystem, which, if you were lucky, was allowed to flourish.

If you weren't so lucky, you were maybe born to germophobic parents, exposed to several rounds of antibiotics, had a girlfriend who put on a latex hospital glove before servicing you in the last row of the movie theater, or, in general, assailed your natural bacterial population with years of antiseptic soaps, disinfectants, mouthwashes, chlorine pools, and various bacteria-killing prescription drugs.

In a manner of speaking, your bacterial ecosystem is the rainforest, and you've willfully introduced unfettered hordes of loggers, farmers, miners, industrialists, and poachers to run rough shod over your system and it's likely given you a severe case of dysbiosis.

In other words, it's likely your bacterial population is out of whack.

Rock Your Bacterial World

Let's get one common misconception out the way. Having a cup of yogurt every day isn't going to do much to repopulate your gut with the right bacteria. There are hundreds or thousands of species of bacteria in your gut and a typical yogurt probably contains two strains of bacteria.

And here's more disheartening news: taking probiotic supplements (pills, capsules, liquids) doesn't often work, either. No study has shown that supplemental probiotics become permanent residents.

Now before you throw the previously cited studies in my face, the one about the mind-controlling yogurt and the mice with bigger balls, it seems likely that particular strains of bacteria – given in high doses over a short period of time – can have medicinal effects, but that still doesn't mean that they become permanent residents.

Part of the problem might have to do with the supplements themselves, which are often victims of mishandling. Capsules and tablets should be refrigerated, not just after you buy them, but also immediately after they were manufactured, during shipping, and at the store. And there's no way to tell if that actually occurred, that some kid with an impressive bacterial infestation on his face didn't take a break to eat a Cheesy Blaster in the middle of stocking the fridge at the local GNC while your probiotics sat in the sun and went to the fermented pickle in the sky.

Speaking of fermented foods, eating them may be a better tactic to take in establishing or maintaining a healthy gut environment. Fermented foods are those produced, transformed, or preserved by the action of micoorganisms, most often lactobaciilus.

Note: The category of fermented foods also contains things like beer and alcohol, but gulping Jell-O shooters off some co-ed's taut belly isn't going to repopulate your gut. You want stuff that of course has beneficial bacteria in it.

Granted, these fermented foods – like the aforementioned yogurt – depend heavily on the action of one or two microorganism (lactobacillus and bifodobacillus), which is only a small sampling of the microorganisms in a healthy gut, but it looks like they may create an environment conducive to the growth of other bacteria in the same way as a rising tide lifts all boats.

Even so, some experimentation is going to be in order to see which fermented foods work for you.

I recommend sampling at least one, but ideally two, of the foods in the following list every day. I'd also try not to get into a fermented rut by trying to eat a variety of them over the course of weeks and months.

  • Kimchi
  • Kombucha (a culture of bacteria and yeasts brewed into a tea)
  • Miso
  • SauerkrautUmeboshi (fermented, pickled plums from Japan)
  • Tempeh (fermented soybeans)
  • Pickles (only those marked "fermented")
  • Yogurt *
  • Kefir

* It's probably best to avoid brands that contain sugar as these supposedly feed competing bacteria. I'd also recommend avoiding any brands that are advertised on TV by women who make orgasm faces when they eat the yogurt. Instead, look for stuff made by shepherds using yak milk or something; stuff that was strained through the burlap underwear of mountain women that has disgusting bacterial clumps in it. And I'm only half kidding.

And if you do decide to go the pill or capsule route, either by themselves or in conjunction with fermented foods, make sure they at least conform to the following standards:

  • The quantities of bacteria are listed in CFUs (colony forming units) and not milligrams.
  • The product is, despite what the label says, refrigerated.
  • The product is encapsulated with a protective medium such as oil, nutrient culture, shells, or coated tablets.

Another thing you might do to tip the scales in your gut's favor is to eat probiotic "prebiotics," but this might well broach your "gimme a break already" threshold. In case it doesn't, prebiotics are plants that contain inulin or fructooligosaccharides (FOS), which are sugars that feed bacteria.

Foods on this list include bananas, onions, artichokes, asparagus, barley, wheat, garlic, and others in varying degrees.

So let's say you do all of this. You become a foster parent to trillions of new bacteria and take them to the zoo and ballgames and stuff. How do you know that it's doing you any good?

In the short term, you might feel less flatulence, become more regular *, experience less bloating in general, get better skin, and notice stools that are more "aerodynamic," which presumably means they'll be Shamu-like in appearance and manner, frolicking in your toilet bowl like so many Sea World performers.

* Elvis Presley should have paid more heed to his bowels. Despite what the obituaries said, Elvis didn't die of drug overdoses, but constipation. The coroner reported that Elvis had an enlarged "megacolon" that was horribly impacted with the clay-like barium from the barium enema he'd had four months prior to his death. Constipation, it seems, plagued him his whole adult life and he had to undergo two Fleet enemas a day.

Over the long term, it might help mitigate any autoimmune system problems you might have, including asthma, skin allergies, irritable bowel, arthritis, etc. It might very well make you more resistant to diseases, too.

Conclusion, Or, It All Comes Out in the End

I'm guessing that the conclusion you've drawn from reading this article is that we've barely scratched the surface of the role bacteria play in our overall health. I'm hoping you've also drawn the conclusion that any unwashed naturopath who tells you precisely what you need to achieve a healthy probiotic ecosystem in your gut needs to be flogged with the haircloth rucksack they carry their herbs in.

Since everyone has a different ecosystem, we can only make some logical assumptions about how to take care of that ecosystem, and hopefully I've at least given you some instructions on where to start.


  1. Brockman, John (editor), "This Book Will Make You Smarter," Harper Perennial, New York, 2012.
  2. Choi, Charles Q, "Probiotic Bacteria May Help Treat Depression," LiveScience website, Aug. 29, 2011.
  3. Dolgin, Elie, "Mice That Eat Yogurt Have Larger Testicles," Scientific American, Friday, May 4th, 2012.
  4. Grady, Denise, "Bacteria in the Intestines May Help Tip the Bathroom Scale, Studies Show," The New York Times, March 27th, 2013.
  5. Luoma, TC, "Luoma's Big Damn Book of Knowledge," City Lights Publishers, San Francisco, 2012.
  6. Radiolab broadcast of "Guts," April 2nd, 2012.
  7. Roach, Mary, "Gulp: Adventures on the Alimentary Canal," W.W. Norton and Company, 2013.