Why Mood Disorder Treatment Should Begin With Gut Bacteria

Filed Under: Digestive Health, Gut Bacteria & Probiotics, Mood & Memory
Last Reviewed 09/04/2015

man lying on couch while therapist writes

Research into the microbiome (microorganisms that share our body space) continues to provide valuable information and techniques we can use immediately to improve our health.

Studying the beneficial bacteria that live in and on the body has been more than just a passing fascination of mine for decades. If you currently have any health problem, or if you want to help prevent any type of future health problem, it’s imperative that you optimize your microbiome.

Balancing and improving the number and variety of beneficial microorganisms in and on your body can dramatically boost your immune system and overall health. I continually get reports that describe (and I personally get to see) almost-miraculous health changes that come from utilizing fermented foods, high-quality probiotics, and fecal transplants. And I’m in discussions on a regular basis with companies and individuals around the world to make sure you have access to highly beneficial techniques and products to create optimal balance.

Gut/Brain Axis

Some of the research I’ve been following comes from France. I’ve explained the connection between stress, mood disorders, and gastrointestinal disease. Depression, anxiety, and sleep disorders are just of few of the more common problems that have been closely linked to intestinal problems.

Researchers have known for a long time about the “gut/brain axis,” or the direct connection to the brain by way of the 10th cranial nerve. But for some reason, they have always focused on the impact the brain can have on the gut—or control from the “top down.” Even the pharmaceutical companies quickly realized that more than 50 percent of those individuals with irritable bowel syndrome also just happen to have mood disorders. This is why antidepressants are some of the most common pharmaceutical treatments for irritable bowel syndrome. (J Psychiatry Neurosci 09;34(3):230–231)

See a list of all articles about Gut Bacteria in the Gut Bacteria and Probiotics Index

It may seem strange to most people that there is a neurological connection between the gut and the brain—and that you can treat the brain with antidepressants and see improvement in bowel problems. But what’s even stranger (to me anyway) is that until just recently, orthodox medicine never considered directly treating bowel problems to improve mood disorders. It’s a two-way street between the brain and the gut. If you change one area, it makes a difference in the other.

Finally, we’re starting to see more work with probiotics and, just recently, studies proving that mood disorders can be controlled from the “bottom up.” In other words, you can effectively treat depression, anxiety, and behavioral problems by normalizing the bacteria in the bowels.

This opens up a whole new avenue of safely and effectively helping a huge segment of the population suffering from all types of psychological problems. It’s no surprise that we’ve started to see dozens of new psychological “illnesses” develop during the same period that we’ve systematically, through diet and lifestyle, eliminated and altered the bacterial flora in our gut. The changes have been so widespread and dramatic that is literally impossible to document and list them all.

Western Diet Destroys Bacterial Balance

I’ve talked about many of the obvious factors, such as the overuse of antibiotics and other drugs that destroy the body’s bacterial flora. We also have universally included chlorine in our public drinking water and instituted pasteurization, gassing, radiation, and the addition of various chemicals to stop bacteria growth in our food products to increase shelf life. The steps we take to eliminate pathogens in our food also happen to destroy the beneficial bacteria as well. And since I’m constantly studying this area, not a week goes by that I don’t uncover some other ubiquitous compound that either destroys or alters the balance of microflora.

One of the culprits the public hasn’t been told about is the artificial sweetener sucralose (sold as Splenda). Studies reveal that Splenda reduces the beneficial bacteria in the intestines by 50 percent. Sadly, most chemical additives, drugs, and altered foods get approval without ever being tested for their effects on bacterial flora. (J Toxicol Environ Health A 08;71(21):1415–1429)

It’s not in the best interest of food processors and the pharmaceutical industry, and I’m sure they will oppose these types of studies. We can only hope that as the public becomes increasingly aware of the connection between our microflora and our health, that more compounds will be subjected to this type of testing. Until that happens, we will continue to see higher numbers of behavioral and psychological illnesses.

We’ve seen an explosion in many of these disorders in just the last couple of decades. After you look at a few statistics (or take a closer look at your neighbors), it’s obvious the writing is on the wall.


At least 10 percent of the entire population reportedly suffers from depression. Three percent of all adults have major depression. In fact, according to the CDC, major depression is the leading cause of disability for Americans between the ages of 15 and 44.

The National Institutes of Health report that at least 40 million American adults ages 18 and older suffer from anxiety disorder in any given year. That’s 18 percent of the entire population. And we’re not talking about mild, brief anxiety caused by a stressful event like a first date or speaking in public. We’re talking about anxiety problems that last at least six months and don’t get better without treatment. This includes panic disorder, obsessive-compulsive disorder, post-traumatic stress disorder, phobias, and generalized anxiety disorder. (Arch Gen Psychiatry 05;62(6):617–627)


Autism is the fastest-growing serious developmental disability in the US. It now affects one in every 88 children and one in 54 boys. It costs a family on average $60,000 a year, and there is no medical detection or cure for the condition. Sadly, the prevalence of autism continues to rise.

I tried to compare autism rates in the US to other countries, but finding those numbers is difficult. In the US, it is often quoted that autism occurs on the average of 66 per every 10,000 individuals, which is somewhat less than what was stated above. However, in Brazil, it is 27.2 cases per 10,000 people, 16.1 in China, 11.7 in Indonesia, 10 in Israel, 16.7 in Portugal, 1.9 in Germany, and 5 in France.

From all indications, it does appear that the US has one of the highest rates in the world. And one other glaring fact has come to light: When compared to non-autistic children, autistic children have lower levels of three critical bacteria in their gut. (PLoS One 13;8(7):e68322)

One study reported an increased administration of oral antibiotics to autistic children during the first three years of life. Others have found higher levels of mercury in the hair and teeth of autistic babies. Mercury, if you recall, has been predominately used as a preservative in many vaccinations, and the number of childhood vaccinations given in the US is one of the highest in the world. (J Dev Behav Pediatr 06;27(2 Suppl):S120–127) (J Toxicol Environ Health A 07;70(12):1046–1051)

Autistic children usually have a number of gut problems. This led researchers at Arizona State University to analyze and compare the gut flora of 20 autistic children to 20 non-autistic children ages 3 to 16. They discovered that autistic children had less variety of bacteria in general—and in particular, less of three strains (Prevotella, Coprococcus, and Veillonellaceae).

We often see the same thing in individuals with heart disease, diabetes, and many other health conditions: They have less gut bacteria and fewer varieties than healthy individuals.

Anger Disorder

Around 7 percent of individuals in the US experience what has now been labeled “intermittent explosive disorder” (IED). (It seems like we have a name or acronym for just about any behavior now. It makes it easier to write prescriptions for drugs when doctors can classify it as a disorder or disease.)

We’re not talking about temper tantrums, but more along the line of road rage or irrational, violent acts like hitting a spouse or loved one or tossing the television out the window during an argument. I spoke with individuals studying the condition at the University of Texas Health Science Center in San Antonio. They differentiate IED from bipolar by the fact that, while both have violent, aggressive outbursts, IED individuals don’t experience the same manic highs as bipolar people.

It’s no surprise that IED has no cure, and common treatment includes antidepressants.


Attention deficit hyperactivity disorder (ADHD) is skyrocketing. One recent report by the New York Times, using data from the CDC, states that 11 percent of all US children ages 4 to 17 have been diagnosed with ADHD. It was estimated that one out of every five boys in high school has ADHD.

Rather than treat these kids from the “top down” with drugs, wouldn’t it be wise to use the “bottom up” method and treat their gut with probiotics? The French look at ADHD differently than we do here in the US, and it should be a wake-up call for us.

In France, the percentage of children diagnosed with ADHD is 0.05 percent, compared to 11 percent of children in this country! (As noted earlier, France also has a very low rate of childhood autism.)

In this country, the powers that be consider ADHD a biological disorder or chemical imbalance that needs to be treated with medications like Ritalin and Adderall. But the French understand that ADHD can stem from social, behavioral, and nutritional problems.

The tools for treating ADHD in France can vary, but they focus on the underlying problem instead of the symptom. They find that some children’s behaviors are linked to social and situational causes, requiring psychotherapy or family counseling. With others, it’s more of a discipline issue that requires a spanking. (That definitely cured a lot of my ADHD issues as a child.) When used judiciously, spanking isn’t considered child abuse like it is here.

The French also realize that diet can be an underlying factor. They understand that behavior in some children gets noticeably worse after consuming artificial colors, preservatives, or sweeteners and/or being exposed to allergens. As a side note, French children are also not allowed to randomly snack at will. Their feeding times are more structured. I can quite vividly remember my mother telling us as children that we couldn’t snack or eat before dinner because it would ruin our appetites. That’s something you rarely hear these days.

Probiotic Combination

In my search for natural therapies for anxiety and depression, I have yet to find anything as effective as the South African plant extract Sceletium tortuosum (sold as Zembrin). But during my research, I ran across some work in France where they have been utilizing specific probiotic strains to improve these same problems. Based on their “bottom up” treatment approach, it didn’t surprise me that they were studying this method. What did surprise me was how effective it was.

The French found that a bacteria combination displayed anti-anxiety characteristics in animals, and then beneficial psychological effects in human volunteers as well.

Laboratory and numerous standardized psychological tests revealed lower levels of the stress hormone cortisol, a significant decrease in symptoms such as depression, anxiety, anger/hostility, obsessive-compulsive actions, phobias, and paranoia, and an improvement in sleep.

In many parameters, the combination probiotic provided very similar results to the drug diazepam (Valium), without any of the side effects. (Br J Nutr 11;105(5):755–764) (Eur J Clin Nutr 09;63(1):100–105)

In other studies, this same probiotic combination product (called Probiostick) has been shown to reduce the depressive behavior that commonly follows a heart attack. It was also found to restore the integrity of the intestinal wall, which acts as a barrier to pathogens entering the bloodstream from the gastrointestinal tract. (Br J Nutr 12;107(12):1793–1799) (Br J Nutr 13;109(1):50–56) (Br J Nutr 09;102(10):1420–1425)

I like Probiostick for several reasons. The product is an easy-to-take powder that comes in a little pouch that you simply open and dump in your mouth. It tastes good and gets through the digestive system quickly. For depression and other mood disorders, I think the combination of Probiostick and Zembrin will be a godsend to a lot of people.

Mood Disorders Don’t Stand Alone

Clinically, doctors have observed that psychiatric illness doesn’t stand alone. Almost universally, there’s a gut connection. Gastrointestinal disorders always seem to accompany psychiatric illness. It may be hard to tell which came first. But based on the trends we have seen over the last few decades, I can’t help but think the constant assault on our intestinal flora is the underlying cause of many of the psychological problems we’re now experiencing.

Regardless of what came first, these studies once again illustrate the inseparable gut/brain connection. They also demonstrate that we have an obvious choice when it comes to treating these problems. Either we can follow the pharmaceutical route and treat the problem from the “top down” by altering the chemistry in the brain, which is akin to playing with fire. Or we can treat the problem from the “bottom up” by repairing the gut and balancing its microflora, without the horrendous side effects associated with psychiatric drugs.

It seems pretty clear to me that those primarily benefiting from the “top down” approach are the pharmaceutical companies. But that’s generally the case when one continues to treat symptoms instead of the true cause of a problem.

Read More About Gut Bacteria and Digestive Health

Gut Bacteria and Probiotics Article Index
See a full list of articles by Dr. Williams about gut flora, probiotics, and the microbiome. Read more
9 Ways That Good Gut Bacteria Support Your Overall Health (That Have Nothing to Do With Digestion)
Learn about the wide-ranging health effects of gut bacteria, including their influence on immune health, mood, and weight management. Read more
Signs That You Have Too Much Bad Bacteria in Your Gut
Learn about the digestive and other health symptoms that may indicate you have dysbacteriosis, or an imbalance of gut bacteria. Read more
Lifestyle Habits That Damage Gut Bacteria
LLearn how our normal, everyday routines can damage the microflora in our gut. Read more
How to Restore and Improve Gut Bacteria
Learn three strategies for restoring your gut health by improving the microflora residing there. Read more


DISCLAIMER: The content of DrDavidWilliams.com is offered on an informational basis only, and is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified health provider before making any adjustment to a medication or treatment you are currently using, and/or starting any new medication or treatment. All recommendations are "generally informational" and not specifically applicable to any individual's medical problems, concerns and/or needs.

Enjoy What You've Just Read?

Get it delivered to your inbox! Signup for E-News and you'll get great content like you've just read along with other great tips and guides from Dr. Williams!