Psychobiotics: How to Use Probiotic Supplements to Biohack the Gut-Brain Connection

Nobody blinks twice when we say gut bacteria influence your digestive system. A lot of people can even get on board with your gut microbiota impacting your immune system. Now, research suggests that microorganisms throughout your intestinal tract can have a significant impact on your mental health. With this mounting evidence, many now use the beneficial effects of probiotic bacteria to biohack their mental health and improve their overall mood. The use of gut microbes to positively influence the human brain is known as psychobiotics. Let’s discuss this fringe topic in the study of gut microbiomes and why good bacteria might be the all-natural treatment your nervous system needs!


What Are Psychobiotics? 

what are psychobiotics?

Welcome to Pyschobiotics 101: What is a Pyschobiotic?

The term psychobiotics is used to describe probiotic supplements that are formulated to improve your brain health. It’s a blanket term that can describe a variety of probiotic formulations. 

Research shows that many bacteria strains can influence physiological functions that will modulate psychological outcomes [1]. In essence, different bacteria can be a good neighbor who saves your cat from a house fire or be the aggressive driver who causes an accident that leads to a traffic jam. 

Yeah, we want less of that guy. However, even that guy serves a purpose in the grand scheme of life. We just have to make sure we help the growth of more kitty savers.

Probiotic supplement companies are now offering these bacteria strains in different blends to support everything from cognitive decline to mood swings to Major Depressive Disorder. 

These blends help bridge the gap in bacterial diversity within your gut. In turn, psychobiotics might help with mild-to-moderate symptoms associated with mental illness and stress.


Which Bacteria Are in Psychobiotics?

Two people can have two completely different psychobiotic probiotic supplements. However, it doesn’t mean they’re both taking the same psychobiotics. This kind of confusion doesn’t happen when you’re buying Vitamin C. You’re just like, “where’s the gummy version?”

Buying a psychobiotic supplement means you are purchasing a supplement fortified with probiotics that are scientifically linked to brain health. It’s up to the company to choose the strains, colony-forming units (CFUs), prebiotics, and other minerals. 

For the general public, a combination of the usual suspects of gut microbes associated with a healthy brain should suffice. However, more advanced mental health cases, such as schizophrenia, would require a more targeted probiotic approach. 

That’s what makes the research of psychobiotics so fascinating. All-natural mental health remedies might become a reality.


How Do Psychobiotics Work?

It’s been long said that the gut is our “second brain.” In fact, the digestive tract has what is known as the “enteric nervous system.”

The enteric nervous system possesses around 500 million neurons that modulate gastric and digestive functions from the esophagus to the colon [2]. 

This continuous line of communication is known as the gut-brain-axis. Evidence suggests that positive mental health benefits can occur via the gut-brain-axis and the use of psychobiotics.

These positive results are essentially regulated by a series of nerve fibers known as the vagus nerve, also termed the wandering nerve.

What is the Vagus Nerve?

The vagus nerve hangs down from the brain stem, ending in the gut. These highly sensitive nerve fibers interact with various gut microbes at all times [3]. The vagus nerve reports these interactions back to the central nervous system. 

Our vagus nerve follows our entire gastrointestinal tract. Therefore, it interacts with every primary organ system along the way. Yet, over 90% of its communications are with gut bacteria [4]. 

From the moment we’re born, the vagus nerve is aware of how a healthy gut microbiome feels. That’s why many who aren’t born with a mental illness don’t show depression symptoms at a young age

Over time, mental disorders develop, coinciding with other factors, such as stress, poor diet, and trauma. These outlying factors cause immune responses on the body that eventually alter gut microbiota composition. 

The vagus nerve picks up on these changes, and it’s not a happy camper! So, it relays the message back to the central nervous system.

Depending on the bacterial species present in your gut, you may experience various symptoms of psychiatric disorders, such as depression, anxiety, and gut issues.

Research suggests that probiotic treatment of psychobiotics can help stimulate the vagus nerve. In turn, you might feel less mental health-related symptoms originating from a gut bacteria imbalance.


How Stomach Bacteria Communicate Through Microbiome-Gut-Brain Axis

microbiome-gut-brain-axis

Let’s take a ride!

Our gut microbiome is teeming with trillions of bacteria, fungi, yeast, and viruses. These microbes influence every physiological process that’s responsible for us being human. Of these trillions of microbes, there are hundreds of bacterial species. 

In the wild, every animal, plant, and insect plays a role in keeping the earth sustainable. Each species in our gut has a place in our internal ecosystem that helps our circadian rhythm and metabolic pathways running smoothly. 

As our gut microbiome becomes compromised by stress, immune responses, poor diet, and other factors, we start to develop different symptoms of any psychiatric illness. When our microbiome is running low on a specific bacterial species, it communicates it to us through the microbiome-gut-brain axis. 

You start to consciously feel the changes in your behavior. The reason why is that your body might not have the gut bacteria necessary to create the amino acids we need for neurotransmitters.

As more clinical studies on psychobiotics become available, we can hopefully start tailoring specific strains to meet the needs of more serious mental health issues, such as Autism Spectrum Disorder, Major Depressive Disorder, or Bipolar Disorder. 


Benefits of Psychobiotics 

benefits of psychobiotics

Benefit the gut. Benefit the brain. Benefit the brain. Benefit the gut.

Using psychobiotics can improve your mental health in a variety of ways. Introducing probiotics into your system is essentially a way for you to communicate with your gut bacteria. You are letting these gut microbes know that you’re aware of the bacterial discrepancy and are experiencing the symptoms they’ve called for you to feel. 

With the use of probiotics, you are actively inoculating beneficial bacteria the microbiome needs. This helps take the burden off the probiotic bacteria already holding down the fort. Here are some scientifically-backed benefits of psychobiotics.

Improves Depressive Symptoms

Did you know that approximately 80% to 90% of your serotonin levels are derived from your gut [5]? The reason why is that your gut bacteria acts as a bouncer to the club. They can lift the velvet rope and decide which amino acids cross the blood brain barrier and get VIP access to the central nervous system. 

Recent studies involving Dawley rats found that Bifidobacteria infantis (B. infantis) intervention helped improve symptoms of depression. 

Boosts Tryptophan Levels

Researchers noted that probiotic intervention caused a significant increase in tryptophan plasma throughout the duration of the intervention period compared to the controls [6]. 

Tryptophan interacts with the tryptophan hydroxylase enzyme. Research shows that Vitamin D helps the body create more of this essential enzyme [7]. 

Unfortunately, the majority of the world has a Vitamin D deficiency. That’s why we include Vitamin D in our custom probiotic recommendations, available through Thryve Gut Health Program

Boosts Serotonin Levels 

When tryptophan hydroxylase enzymes interact with tryptophan, it creates 5-hydroxytryptophan (5-HTP). 5-HTP then interacts with the aromatic amino acid decarboxylase enzyme to create serotonin [8].

Serotonin influences so many vital human functions, including:

  • • Mood
  • • Sexual Appetite
  • • Digestion
  • • Circadian Rhythm
  • • Sleep Patterns
  • • Blood Clotting
  • • Bone Health

That’s a lot of responsibility for one neurotransmitter. Naturally, our body gobbles serotonin up, causing people to get prescription medications for serotonin reuptake inhibitors (SSRIs). 

More human trials are needed, but hopefully, the use of probiotics might help lessen the dependency on prescription medications over time [9]. You should definitely speak to a doctor before making any significant changes to your health regimen. 

Produces Butyrate 

Probiotic bacteria are the gift that keeps on giving. Part of their job is to help us digest foods. In particular, they break down the dietary fibers we can’t. These foods are known as prebiotics and help probiotic bacteria grow stronger.

Like us, probiotics must expel waste. Their trash is our treasure. That’s because probiotics enrich our gut microbiome with short-chain fatty acids. In particular, they produce butyrate. 

Butyrate helps repair the epithelial cells that line our gut barrier [10]. That way, potential toxins and pathogens don’t infiltrate the human body and disrupt important biological processes in the brain. However, butyrate does even more to benefit the microbiota-gut-brain axis!

A meta-analysis of this short-chain fatty acid found,

“Butyrate’s ability to act as a neuroprotective agent together with its effects on memory and cognition is of particular interest given that loss of cognitive abilities is a long-recognized and undertreated feature of recurrent and severe depressive disorders [11].”

British Journal of Pharmacology

Butyrate is derived from fat. So, if you suffer from obesity, this short-chain fatty acid can be troublesome. Life is about balance.

Other short-chain fatty acids, such as acetate and propionate, have also exhibited anti-depressive properties. Getting a wide range of short-chain fatty acids is dependent on a broad spectrum of intestinal flora. This evidence further proves the importance of bacterial diversity. 

Helps with Anxiety Disorders

More animal studies confirm that psychobiotics can have a positive impact on emotional states. One study fed genetically-anxious mice strains of Lactobacillus rhamnosus (L. rhamnosus) [12]. 

Results found that the mice who consumed L. rhamnosus were less apprehensive about partaking in a swim test. 

This lack of fear led experts to believe that the mice were less anxious. Their deductions were proven correct, as psychobiotics helped in two fashions. 

Lower Cortisol Levels

Researchers noted that the mice fed L. rhamnosus had lower cortisol levels when compared to the control. Cortisol is one of the most widely influential stress hormones. It causes a heightened sense of panic and the overwhelming dread associated with anxiety disorders. 

For those who endure chronic stress, cortisol levels can skyrocket. In turn, they experience other hormonal imbalances, including sexual dysfunction and infertility. These issues can only further impact behavioral disorders negatively.

Boosts GABA Levels

Scientists also noted that the mice who consumed this Lactobacillus species also saw a significant increase in gamma-Aminobutyric acid (GABA). 

GABA is a neurotransmitter that helps calm excited neurons in the brain. It’s known as our “inhibitory neurotransmitter [13].”

Those who experience symptoms of anxiety have overactive communication in the brain. GABA binds to these chatty neurons so that the traffic in your mind slows down. In turn, you’re less susceptible to anxious thoughts and can perform with improved cognitive function. 

Neuroprotective Abilities

Psychobiotics don’t just help with the long-term damage caused by a life of stress, poor diet, and other trauma. It can also prevent issues, such as Alzheimer’s Disease, from developing down the road. 

These beneficial stomach bacteria have been shown to improve immune responses in the system. Therefore, you are less likely to experience chronic inflammation that can destroy healthy brain cells or grey matter.

The two most common bacterial strains found in psychobiotics are Bifidobacteria and Lactobacilli. 

A meta-analysis of the efficacy of probiotic interventions for mental health found that Bifidobacteria and Lactobacillus strains:

“Do not possess pro-inflammatory lipopolysaccharide chains, and so their propagation in the gut does not trigger full-fledged immunological reactions. With the presence of such bacteria, the immune system learns to distinguish to between pro- and anti-inflammatory entities and develops appropriate immunogenic responses by identifying pro-inflammatory elements as antigenic [14].”

Trends Nueroscience

Their presence helps the immune system make better decisions as to where to foster inflammation. Not only do these bacteria help brain function, but they save skin cells, blood cells, and other healthy bacteria, too!

Autism Spectrum Disorder Prevention and Care

Human studies have found that children diagnosed with Autism Spectrum Disorder tend to lack diversity in the gut microbiome. One meta-analysis looked at Autism Spectrum Disorder and the gut-brain-axis [15].  

They found that children with autism tended to have lower levels of the following bacterial species when compared to children who don’t have the condition:

  • • Veillonellaceae
  • • Coprococcus
  • • Prevotella 

Animal studies involving mice with autism-like behavior also found another strong connection between this condition and the gut-brain-axis, noting:

“When mice with an autism-like condition had lower levels of Bifidobacterium and Blautia gut bacteria, their guts made less tryptophan and bile acid — compounds needed to produce serotonin.”

Nature

See, it all connects! Lastly, the meta-analysis looked at a study comparing the guts of germ-free mice (gf mice) with autism to those who had a regular gut microbiome. In comparison, the gf mice with autism had fewer metabolites, such as amino acids 5-aminovaleric acid (5AV) and taurine. 

These two amino acids play an essential role in GABA production. Therefore, probiotics help create metabolites that improve mental health.


Types of Psychobiotics 

Many bacterial strains are associated with positive psychiatric effects. Whether you have social anxiety, Seasonal Affective Disorder, or an eating disorder, the use of probiotics might have positive effects on your emotional states and cognitive function. 

Our team of scientists at Thryve worked hard to formulate a blend of probiotic bacteria that help support cognitive function, circadian rhythm, and mood. That way, you can wake up feeling refreshed, focused, and full of self-esteem! Let’s discuss the strains in the Thryve Mood Enhancer Specialized Probiotic Supplement.

Thryve Mood Enhancer Psychobiotic Supplement

Thryve Mood Enhancer psychobiotic supplement gut bacterial strains

Enhance your mind and body with Thryve Mood Enhancer

Thryve Mood Enhancer is optimized with a proprietary probiotic blend of Lactobacillus plantarum PS128™ and Lactobacillus paracasei PS23™. They are combined with other bacteria that are beneficial to the human gut and mind. Let’s discuss these strains and the clinical studies that prove their efficacy in mental health care.

Lactobacillus Species 


Thryve Mood Enhancer contains six bacterial strains classified as Lactobacillus families. Each plays a role in physiological functions associated with mental and cognitive health. Let’s take a closer look at each strain. 

Lactobacillus plantarum PS128

A clinical study in 2019 concluded Lactobacillus plantarum PS128 improved hyperactivity, anxiousness, and impulsive behaviors of children with Autism Spectrum Disorder [16]. The study noted previous animal studies where this bacterial strain increased corticosterone (cortisol) levels in mice. 

Furthermore, mice had increased levels of dopamine in the prefrontal cortex. This area of the brain is responsible for memory and learning new concepts. 

These findings corroborated a 2016 clinical study where gf mice saw an increase in dopamine and serotonin after probiotic intervention with Lactobacillus plantarum PS128 [17]. 

Lactobacillus paracasei PS23

In a 2019 clinical study, L. paracasei PS23 improved depression-like and anxiety-like behaviors via reversing “corticosterone-reduced dopamine levels and serotonin levels” in the hippocampus, striatum, and prefrontal cortex [18].

The hippocampus plays a significant role in long-term memory storage. Our striatum is responsible for decision-making skills and analyzing risk-reward. That’s why dopamine is so essential for this part of the brain. Lastly, the prefrontal cortex is in charge of cognitive processes and working memory.

Lactobacillus plantarum 14D

A 2018 clinical study concluded Lactobacillus plantarum exerts beneficial effects on the gut-heart-brain axis, contributing to brain health and improving psychological disorders [19]. 

Another meta-analysis of the gut-brain-heart-axis explained that gut microbiota could influence the vagus nerve to cause the brain to produce neuropeptides [20]. 

These are tiny polymers that act as neurotransmitters. They can influence “neuro-enteric plexus, POMC, circadian clock and amygdala.” 

Depending on the foods, such as too much red meat, these neuropeptides can trigger heart disease. That’s why it’s vital to maintain microbial balance with Thryve Mood Enhancer

Lactobacillus delbrueckii ssp. bulgaricus LB2

Research indicates that Lactobacillus delbrueckii ssp. bulgaricus LB2 is effective in thwarting off the overgrowth of Helicobacter pylori (H. pylori), inhibiting the growth of 53.3% H. pylori strains. [21]. 

H. pylori infections can cause severe depression. One meta-analysis found women over 50 were susceptible to feeling depressive symptoms due to increased risk of H. pylori infection [22].

Lactobacillus acidophilus

In a 2019 clinical study, Lactobacillus acidophilus provided neuroprotective effects of mice. The results noted that probiotic intervention curbed pro-inflammatory biomarkers TNF-α and IL1-β from destroying cells in the perilesional cortex [23].

Additionally, the mice’s intestinal barrier permeability improved. Intestinal permeability is another way to say Leaky Gut Syndrome. This realization lends even more credence to the gut-brain-axis. 

Lactobacillus paracasei 101/37 

A clinical trial about anxiety and probiotic intervention with Lactobacillus paracasei 101/37 found that this strain might help manage stress and anxiety [24]. 

These gut microbes influence the hypothalamic-pituitary-adrenal (HPA) axis. The HPA axis is responsible for our adrenal glands producing cortisol. 

Bifidobacterium Species 


Bifidobacterium has become increasingly linked to improved emotional states. Let’s take a look at the strains we chose to include the Thryve Mood Enhancer psychobiotic supplement. 

Bifidobacterium breve Bbr8

A 2019 clinical study found that a probiotic blend containing Bifidobacterium breve Bbr8 can significantly improve symptoms of Irritable Bowel Syndrome (IBS) [25]. 

Another study looked at how IBS-C and IBS-D affect the mental health of those who have these diagnoses [26]. Results found that regardless of which type of IBS they have, those diagnosed with IBS are more likely to develop anxiety and depression. 

Bifidobacterium breve BL10

A 2018 study looked at mice who were fed a high-fat diet, much like those who follow a Western Diet [27]. These mice developed obesity. 

They were treated with a probiotic blend that contained Bifidobacterium breve BL10 and Bifidobacterium breve Bbr8, both found in Thryve Mood Enhancer

Results found that these gut microbes regulated leptin levels. Leptin tells your brain that you have enough energy stored in the fat so that you stop eating [28]. That’s good for people with obesity who have mental health issues. 

After all, one study found a bidirectional link between obesity and Major Depressive Disorder. Those who are obese are 55% more likely to develop depression, and people who experience depression are 58% more likely to develop obesity [29].

Bifidobacterium animalis ssp. lactis Bi1

This probiotic strain is a potent neuroprotectant. A meta-analysis of Bifidobacterium animalis ssp. lactis Bi1 found that this bacteria strain stops toxins from penetrating the blood brain barrier. These gut microbes stopped 99% of aflatoxins and genes that might cause damage to brain tissue [30]. 

Streptococcus thermophilus Z57 


Last is certainly not least here. Streptococcus thermophilus Z57 rounds out the Thryve Mood Enhancer psychobiotic supplement. 

A 2019 study on mice with Multiple Sclerosis (MS) found,

Streptococcus thermophilus induced a significant increase in the expression of anti-inflammatory IL-4, IL-5, IL-10 cytokines, and decreased the secretion of pro-inflammatory IL-1β and IFN-γ [31].”  

Brain Sciences

These benefits are not just great for autoimmunity; they’re excellent for preventative brain health. Less inflammation in the system will improve sleep patterns, circadian rhythm, focus, and mood. 


The Future of Psychobiotics

 

Psychobiotics are a relatively new supplement product market. More human trials are needed…and coming. The future of psychobiotics is very exciting. That’s why we are happy to use the science that’s already out there to create a targeted psychobiotic blend with Thryve Mood Enhancer.

With time, we hope that psychobiotics can offer a tailored approach to mental health care. Perhaps people can eventually use a live organism to manage their depressive systems rather than prescription medications with horrible side effects. 

However, that’s down the line. Please talk to your doctor before making any significant changes to your health routine.

Thryve Probiotics Gut Health

https://thryveinside.com

Resources


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[19] Liu, Y. W., Liong, M. T., & Tsai, Y. C. (2018). New perspectives of Lactobacillus plantarum as a probiotic: The gut-heart-brain axis. Journal of microbiology (Seoul, Korea)56(9), 601–613. https://doi.org/10.1007/s12275-018-8079-2.


[20] Singh, Ram B., et al. “The Gut-Brain-Axis and the Heart.” MOJ Public Health, MedCrave Publishing, 14 June 2018, medcraveonline.com/MOJPH/the-gut-brain-axis-and-the-heart.html.


[21] Boyanova, L., Stephanova-Kondratenko, M., & Mitov, I. (2009). Anti-Helicobacter pylori activity of Lactobacillus delbrueckii subsp. bulgaricus strains: preliminary report. Letters in applied microbiology48(5), 579–584. https://doi.org/10.1111/j.1472-765X.2009.02571.x.


[22] Al Quraan, A. M., Beriwal, N., Sangay, P., & Namgyal, T. (2019). The Psychotic Impact of Helicobacter pylori Gastritis and Functional Dyspepsia on Depression: A Systematic Review. Cureus11(10), e5956. https://doi.org/10.7759/cureus.5956.


[23] Ma, Y., Liu, T., Fu, J., Fu, S., Hu, C., Sun, B., Fan, X., & Zhu, J. (2019). Lactobacillus acidophilus Exerts Neuroprotective Effects in Mice with Traumatic Brain Injury. The Journal of nutrition149(9), 1543–1552. https://doi.org/10.1093/jn/nxz105.


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[25] Francavilla, R., Piccolo, M., Francavilla, A., Polimeno, L., Semeraro, F., Cristofori, F., Castellaneta, S., Barone, M., Indrio, F., Gobbetti, M., & De Angelis, M. (2019). Clinical and Microbiological Effect of a Multispecies Probiotic Supplementation in Celiac Patients With Persistent IBS-type Symptoms: A Randomized, Double-Blind, Placebo-controlled, Multicenter Trial. Journal of clinical gastroenterology53(3), e117–e125. https://doi.org/10.1097/MCG.0000000000001023.


[26] Lee, Changhyun, et al. “The Increased Level of Depression and Anxiety in Irritable Bowel Syndrome Patients Compared with Healthy Controls: Systematic Review and Meta-Analysis.” Journal of Neurogastroenterology and Motility, Korean Society of Neurogastroenterology and Motility, 1 July 2017, www.jnmjournal.org/journal/view.html?doi=10.5056%2Fjnm16220.


[27] Roselli, Marianna, et al. “Beneficial Effects of a Selected Probiotic Mixture Administered to High Fat-Fed Mice before and after the Development of Obesity.” Journal of Functional Foods, Elsevier, 21 Apr. 2018, www.sciencedirect.com/science/article/abs/pii/S1756464618301257.


[28] Society for Endocrinology. “Leptin.” You and Your Hormones, Mar. 2018, www.yourhormones.info/hormones/leptin/.


[29] Floriana S. Luppino, MD. “Overweight, Obesity, and Depression.” Archives of General Psychiatry, American Medical Association, 1 Mar. 2010, jamanetwork.com/journals/jamapsychiatry/fullarticle/210608.


[30] Ghazvini, R. D., Kouhsari, E., Zibafar, E., Hashemi, S. J., Amini, A., & Niknejad, F. (2016). Antifungal Activity and Aflatoxin Degradation of Bifidobacterium Bifidum and Lactobacillus Fermentum Against Toxigenic Aspergillus ParasiticusThe open microbiology journal10, 197–201. https://doi.org/10.2174/1874285801610010197.


[31] Dargahi, Narges, et al. “Streptococcus Thermophilus ST285 Alters Pro-Inflammatory to Anti-Inflammatory Cytokine Secretion against Multiple Sclerosis Peptide in Mice.” MDPI, Multidisciplinary Digital Publishing Institute, 23 Feb. 2020, www.mdpi.com/2076-3425/10/2/126/htm.