Can probiotics help treat depression and anxiety?

Athos Bousvaros, MD
Athos Bousvaros, MD, Contributor

There is a lot of interest right now in the human microbiome (the populations of bacteria that live in various parts of the body, including the intestine, skin, and lungs). We now know that there are approximately 10 times as many bacterial cells as human cells in the body. The vast majority of these bacterial cells are in the intestinal tract, and they serve many purposes, including digesting foods, manufacturing certain vitamins (for example, vitamin K), and regulating our immune system. Researchers are actively studying whether changes in intestinal bacteria can increase the risk of chronic illnesses, such as obesity or inflammatory bowel disease.

Is the way to your brain through your stomach?

Interest is also developing in the so-called “brain-gut axis.” It has been theorized that changes in intestinal bacteria may play a role in neuropsychiatric conditions such as anxiety or depression. The intestine has its own separate nervous system, and generates many of the same neurotransmitters (including acetylcholine and serotonin) that the brain generates. These neurotransmitters are very important in promoting gut motility, and too much or too little of them may result in constipation or diarrhea. Similarly, we believe that the brain and the gut can talk to each other. Therefore, it is possible that anxiety and depression may trigger abdominal pain or other GI symptoms. It is also possible that gastrointestinal conditions such as chronic abdominal pain or constipation might also result in anxiety or depression.

Can probiotics treat chronic conditions (physical and mental)?

If, in theory, bacteria have a role in these chronic conditions, perhaps changing the intestinal bacteria by adding probiotics (“good bacteria”) might help treat chronic illnesses. Probiotics have been utilized widely in countries like China and Japan for decades, primarily in the form of fermented milk. In addition, there are a number of animal studies that suggest probiotics may be helpful for conditions like diarrhea or colitis. Unfortunately, probiotics have not yet been shown to treat much human disease.

A recent article in Annals of General Psychiatry reviewed the currently available medical literature on using probiotics to treat anxiety and depression. The doctors identified 10 studies that were well done (in other words blinded and placebo-controlled), and looked at each study in depth. All of these studies had relatively small numbers of patients, ranging as from as few as 42 to as many as 124. The results of these studies were mixed; some suggested that there may be mild benefits of taking probiotics if you have anxiety or depression while other studies showed no benefit. Overall, the authors concluded “the clinical effects of probiotics on mental health have yet to be studied comprehensively.”

The bottom line

While it is tempting to hope that probiotics may be used to treat anxiety or depression, at this point there are no compelling data that suggest a true benefit. Since most probiotics are relatively safe, taking them for this reason probably falls into the “doesn’t hurt, and might help” category. However, probiotics are probably not a substitute for standard care such as cognitive behavioral therapy, or FDA-approved drugs to treat depression or anxiety. More research as needed in the future, that should try to identify which strains of bacteria are the most effective and the best dose of bacteria to take to treat these conditions.

Comments:

  1. Sarvika Bommakanti

    Dr. Bousvaros, thank you for this article as it was really interesting to read. Since probiotics may have a positive effect on anxiety and depression, do you think other digestive supplements may have a similar effect since the brain and gut are interconnected? Thank you!

    • Athos Bousvaros

      There have been some studies that suggest St. John Wort can help depression. However, there have also been side effects described with that supplement, and St. John Wart can interact with many presciption medications. As always, if you plan to treat any illness, you should review the risks and benefits of any therapy with your physician. As a disclaimer, I am a gastroenterologist, not a psychiatrist.

  2. Darrin Duvall

    I can honestly report.
    I no doubt had very serious depression. Never diagnosed. But being angry always, sleeping way to much, didn’t want to go to work and didn’t alot. Gained a lot of weight, Putting lots of task aside for tomorrow. Then still not doing them. Just wasn’t happy about anything. Of course I made alot of rediculous excuses.
    Well. My eye sight suddenly really bad.
    I went to the eye doctor. She said I better go to a medical doctor. I did. My bad colesterol was through the roof, my good colesteral was low my triglycerides were at dangerous level. And Blood Glucose and A1c proved I was diabetic.
    Scared the hell out of me.
    So started personal research hoping to find out every thing I could to keep from taking injections and other Medicare the rest of my life. And spending about $800.00 a month on them. One of the I discovered and educated myself on was how to eat right for real. Not someone’s diet plan thays being sold or magic formula or medication. And yes there is plenty of those scavenger bottom feeders out there.
    One artical I read. Which I crossed referenced every thing I read. Was about the bennifit of probiotics and other types of food and spices that will help you creat and release dopamine to your brain naturally. BONANZA!!!!! Every thing the article said just sounded right and made complete since. So that’s where I started.
    Since then almost exactly 4 months ago my mental focus is spit on, I lost 80 pounds, my mood has been incredible since the first couple of weeks, I sleep perfect, my house is very clean, I make more money at work, I’ve been very active in lots of different ways. The list goes on and on. Can not tell you how extreme the effects have been on my life. Not once I did not intentionally exercise at all other than work, which is some what physical. My customers not only have committed on my weight loss, but regularly compliment me on on my attitude and mood. More Importantly. I have 4 grown children every one of the has honestley said to me in one way or another, that I have been very pleasurable to be around. I have even had very good conversations with my ex wife. “Which by the way was one of my many excuses” And My doctors visit this morning was nothing but good news. He actually said. ” Your blood work today and what I see from 4 months ago are like two completely different people. How did you do it?” So I told exactly what I’m telling saying in this comment.
    About Googling everything I have eaten for 4 months with an emphasis startin with Probiotics.
    He also said there is absolutely no sign of you being diabetic. And to top it off I by regularly checking my blood sugar level to make sure. I only took 3 of the weekly injections the first 3 weeks of my 4 month transition. And about a month ago I quit taking the other meds he prescribed. He couldn’t hardly believe that also. I have literally have maDE a complete transition. My energy level and all blood work my mood and attitude are beyond excellent. Including blood pressure.
    Not once did I starve or even felt very hungry. The first few weeks yes I missed having a coke, starchy foods, and junk food. No processed food ever.. And today I have zero urge for any of it. I have another 20 pounds I will loose. But to me. That is a goal that I know I will accomplish soon. All of that in 4 months a define 20 pounds a month gone. And to top it off. Great health and my focus, attitude mood and of course sex drive is excellent.
    I’m going to turn 51 in two days. And I honestly think I haven’t felt this good in 20 years.
    There is no exaggeration here. And I’m not here to sale any thing. I just think people need to know it’s possible and Probiotics was a perfect place to start.

    Sincerely Darrin Duvall

    .

  3. Suzanne Francoeur

    I have been taking probiotics for 2 years now. I also eat foods with probiotics in them. I have regular bowel movements not constipated all the time. I used to have a bowel movement every three weeks. Now I go daily and amazingly same time in morning. Unbelievable I also believe they help my skin issues. I have dermographism hive and chronic idopatic uthecaria. It seems to have helped. I have all kinds of environmental allergies and had a serious back injury and 3 Neurosurgeons told me I could not have surgery due to going septic on the operating table. So I have apple size holes in my skin and was loosing my limbs. So I would of tried anything to help me heal so I could get surgery. But to late to due the surgery now the Specialist say I will be in wheelchair 90 percent. Which I could of found something to help 4 years ago. Now I am in a wheelchair somethings walker or crutches. I will still continue with probiotics and fermented things like Kombucha. Thank you for your time. Suzanne

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  4. David Shanen

    When I was being properly treated for Lyme disease (only a few doctors seem to TRULY know how to do so!), I had to take probiotics. It was a high dose of doxy, and a second one that rotated with another second ABX (also higher doses than 99% of doctors realize is needed to get to them where they hide out — or even that these ABX ALL cross the blood-brain barrier. (The people at a well-known “center” in NYC were CLUELESS.). AND there was a 3rd drug, 3x/wk to break open the biofilms where the bacteria can and DO hide out for years – biofilms the ABX cannot get through. NATURALLY, the LLMD (Lyme Literate Medical Doctor) who FINALLY got the right tests (not the cheap ones) and knew that it is a CLINICAL diagnosis (the readings of IgG and IgM antibiodies from nearly all labs are WORTHLESS).
    Well, it was a lot to take for 1-1/2 years, but it WORKED!!!!!!!!!!! And I could TELL in many ways. (As a former medical researcher, I could explain in detail, but you’d fall asleep.)

    YOU ARE, BY NOW, ASKING, WHAT DOES ALL THIS HAVE TO DO WITH PROBIOTICS??
    Well, he had me take good priobiotics (even just decent ones were good, not the super expensive ones he recommended), along with a few other things like Milk Thistle at a reasonable dose (REASONABLE) to protect the liver, and MODEST doses of omega-3 oils (3, 6, 9 — you all know the drill). NOT HUGE AMOUNTS, AND NOTHING FANCY. Just something from one of the good places in California (a place that actually RECOMMENDED A COMPETITOR WHO THEY SAID MADE A VERY GOOD MIX if one wanted a different ratio of EPA to DHA oils.

    OK, finally: maybe it was the whole mixture. (My wife did not take any of this and she really NEEDED it all for other reasons — and she went on feeling awful.) ALL I KNOW IS THAT SOMETHING IN THAT REGIMEN MADE ME FEEL BETTER THAN EVER BEFORE — AND THIS WAS LONG BEFORE THE LYME WAS FINALLY (AFTER 8 YEARS) CLEARED FROM MY BOTH AND MY CENTRAL NERVOUS SYSTEM. I THOUGHT MORE CLEARLY. MY MOOD WAS BETTER. MY DEPRESSION ABATED SIGNIFICANTLY AS DID MY EXTREME ANXIETY DISORDER. (Did my psychiatrist believe any of this? Of course not.)

    Yes, probiotics did make a HUGE difference for me, as did the other thing (in MODEST doses!!!).

    (The antibiotics for the Lyme had to be in fairly large doses (and 3 things at once for about 18 months — but when I got the Jarisch-Herxheimer reaction (you cannot miss it!), it was really clear — and doctors I know who live in Lyme infested areas were CLUELESS. It was MUCH, MUCH, MUCH MORE EFFECTIVE THAN DRIPPING IV Rocephin into a PIC line every night for 28 days. But that famous center is just 3 doctors who barely know each other and get together for a photo once a year.

    ANYWAY — yes, I experienced major benefits for my anxiety and depression with priobiotics. They don’t have to be fancy and super expensive. I find that just eating good yogurt helps a lot!!!!!

    Try it. Give it a few weeks. Ingest a good amount of water and stay away from junk food and excess processed sugars and food that’s made from grinding up stuff you wouldn’t want to think about.

    Priobiotics are not present in sufficient amounts in most American food. It’s up to you. Take it from me. Decades of suffering (since BEFORE the Lyme) were helped tremendously with the probiotics, and a couple of other modest supplements.

    Just look up what William Burroughs meant when he came up with the title of his book Naked Lunch. He was WAY ahead of his time. And no one was selling probiotics back then!

  5. Holly

    I believe there is no good reason _not_ to vigorously pursue research into the area of pre- and pro-biotics, the microbiome, and the brain-gut axis. There is also no reason to pit the pursuit of disease cure and prevention through such research against conventional symptom management which is many times also needed, but obviously, whenever a cause for disease is found permanent cures should be sought. Omission in this regard would be unethical of the medical and scientific communities.

    • Jay Somasundaram

      The meta-anlaysis that this article cites (https://annals-general-psychiatry.biomedcentral.com/articles/10.1186/s12991-017-0138-2) is actually quite positive and well worth reading. Its conclusion is , ” The evidence for probiotics alleviating depressive symptoms is compelling but additional double-blind randomized control trials in clinical populations are warranted to further assess efficacy.”

      What seems to be missed out is that along with probiotics, we need prebiotics – sufficient food to ensure a healthy colony. Humans and their biome probably evolved when we consumed far more fibre than currently recommended.

  6. Maggie

    Yes, proper nutrition and probiotics do heal the body and brain, which heals suffering.

    • Maro

      As well consuming fresh yoghurt one hour daily before bed time will avoid constipation problems, as I used probiotc tablet for period of time but it didn’t work.

  7. Ken

    Unfortunately, people will need to discover how to heal themselves through proper prebiotic and whole food nutrition and probiotic supplements because neither the medical profession nor big pharma is economically willing or institutionally able to change. It amazes me that fecal transplant therapy, which has a cure rate as high as 90% for c. diff., is all but ignored as a possible treatment for other illnesses. I discount information coming from establishment medical groups and associations. I believe more and more folks are discovering the benefits of probiotics for physical and mental health, but too many people still rely on the medical-pharmaceutical establishment to heal them while what it mostly does is treat symptoms with drugs that have multiple side effects. I am hopeful that even many cancers can be eliminated through fecal transplants and nutrition plans designed to feed the good bacteria, starves or kill bad bacteria, and stimulate the immune system to do the job it was designed to do.

    • Regina

      I feel your points are well considered. As someone dealing with celiac disease, I am acutely aware how good health begins with digestive system.

    • Rudy

      With sooo much information floating around the internet these days, people have a wealth on information to be reading – some of it’s true, some of it’s unproven, and some of it’s blatantly false.
      But more & more people are going to begin taking their health into their own hands and try to treat diseases with various non-traditional options.

      I have to admit I’m one of those persons.
      I have high hopes that my probiotic supplement are doing me some good!

  8. David

    People have cured all kinds of mental illness with fecal transplants. The US military is currently investigating one probiotic for PTSD.

    Doctors and scientists have got to get with it. And, more importantly, they have to start practicing medicine based on evidence, not just tradition. What evidence is there that the microbiome does not affect health, mental or otherwise? Not seeing it.

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