Articles

Evidence based

Evidence Based

This article is based on scientific evidence, written by experts and fact checked by experts.

Our team of licensed nutritionists and dietitians strive to be objective, unbiased, honest and to present both sides of the argument.

This article contains scientific references. The numbers in the parentheses (1, 2, 3) are clickable links to peer-reviewed scientific papers.

You Can Use Probiotics for Stress Relief: Here’s How

Written by Dr. Ruscio on May 12, 2023

Written by Dr. Ruscio on May 12, 2023 — Reviewed by Hannah Hamlin

Understanding How Probiotics for Stress Can Make All the Difference

• Gut-Stress Connection|
• Probiotics for Stress|
• Probiotics for Stress Protocol|
• Natural Stress Management Therapies|
• Summing it Up|

We’re often pulled in all different directions between work, family, and friendship commitments, so stress is a common feature of our modern lifestyle. If not addressed, over time, we can easily begin to experience the symptoms of chronic stress like fatigue, anxiety, depression, poor mental health, and gastrointestinal distress. In Healthy Gut, Healthy You, I share the story of my patient, Sue. She lived in a high-stress environment for several years, and in order to fit everything into her packed schedule, she sacrificed healthy sleep and her own self-care. Ultimately, her quality of life began to suffer, she started to feel bloated constantly, she was constipated, and she noticed she reacted to foods she previously enjoyed with no problem. 

What was happening to Sue is pretty common. Connecting the dots, here’s what may have been happening: stress was damaging the gut environment leading to small intestinal bacterial overgrowth (SIBO), which manifested as a bunch of symptoms known as irritable bowel syndrome (IBS), fatigue, and insomnia, which further fueled an abnormal stress response.

While mind-body therapies like meditation, yoga, and time in nature are often recommended as natural ways to combat stress [1], probiotics for stress are an important and effective option you may not have considered. Altered stress hormones (like cortisol), fatigue, anxiety, depression, and poor sleep are often the byproducts of poor gut health. By targeting the upstream cause with probiotics, which work in a variety of ways to improve gut health and modulate cortisol levels [2], we can restore a more normal stress response and increase your stress resilience [3, 4]. In fact, research has shown an altered stress response to be a major driver of IBS symptoms, and probiotics seem to improve IBS by impacting the stress response [2].

In this article, I’ll share what we know about the bi-directional connection between the gut and the brain as it relates to stress, and how using probiotics for stress can be a highly effective option for improving your symptoms. Let’s first spend some time on the gut-stress connection.

The Gut-Stress Connection

The gut and the central nervous system are intimately connected, and they communicate with each other constantly via the vagus nerve (gut-brain axis) to impact hormonal systems, neurotransmitters, emotional states, and more. 

It’s important to understand that this is a bi-directional relationship, not a one-way street. While research shows the brain regions that control emotion can be impacted by what’s going on in the gut, so too can the gut be impacted by what’s going on in the brain [3, 5]. When left unchecked, stress can create a cycle of gut microbiome disruptions (leaky gut and dysbiosis), which lead to more stress, anxiety, and depression, but also to functional gastrointestinal disorders like IBS [3, 6].  

Part of the explanation here is that stress, depression, anxiety, and gut dysfunction are all associated with inflammation [7]. When inflammation is present (whether from a dysregulated stress response, poor diet, or infection) in the gut, dysbiosis (an imbalance of microorganisms) and leaky gut can result, which allows a toxic bacterial metabolite called lipopolysaccharide (LPS) to cross the intestinal barrier and enter the bloodstream. Once in the blood, LPS can then cross the blood-brain barrier triggering neuroinflammation and gut-induced stress to create [8, 9]:

• Anxiety
• Depression
• Severe fatigue
• Loss of appetite and thirst
• Worse leaky gut
• More stress

We’ve seen with randomized controlled trials that LPS given to healthy people leads to dramatic increases in inflammatory markers and anxiety [10]. And people with the highest increases in cortisol levels (a stress hormone) after being exposed to stressors like public speaking have worse leaky gut, which further demonstrates the connection between gut dysfunction and the stress response [11].

In addition to inflammation, the levels of protective brain-derived neurotrophic factor (BDNF) also play a role in the stress response. People who have low levels of BDNF tend to have more anxiety, depression, fatigue, and worse cognitive function [12]. Exercise can increase BDNF levels, and when exercise is performed before stress exposure, the cortisol stress response is normalized [12]. Healing the gut microbiome can also increase BDNF levels, which may translate into a more resilient stress response [13].

While more research is needed overall, lowering the inflammatory burden by positively shifting the gut environment seems to be a great way to increase BDNF and minimize the inflammation-induced effects of stress.  Let’s take a look at how probiotics (beneficial bacteria) resolve underlying gut issues to positively impact the stress response. 

Probiotics for Stress

Probiotics exert their positive effects in multiple ways, including by rebalancing your gut bacteria and other gut microbes, reducing inflammation, and, as we’re now learning, normalizing levels of the stress hormone cortisol. 

I recently shared a video unpacking a very important study. Even though it wasn’t a double-blind or placebo-controlled trial, it clarified an important link between gut health, the microbiome, and the stress response, especially for people with IBS.  

At the start of the study, the women with IBS, anxiety, and depression had a lower-than-normal cortisol awakening response (a fairly accurate marker of the stress response), which is the opposite of what we want. Cortisol should be robust in the morning so you can wake up and tackle the day. 

Once these women were given probiotics for 4 weeks, they experienced improvements in their morning cortisol levels, as well as symptoms of anxiety and depression. These benefits continued, and at 8 weeks the probiotics were discontinued. At week 12 (after not having probiotics for 4 weeks), morning cortisol levels had again dropped, and by week 16, cortisol levels were back to baseline, and the women had worse symptoms of anxiety and depression. This study showed that a dysregulated stress response is a likely culprit in the development of IBS and that people with IBS tend to have dysregulated cortisol levels. Treatment with probiotics directly improved cortisol levels and stress symptoms. 

In addition to their cortisol-regulating benefits, probiotics target the gut microbiome. Since the gut and brain communicate with each other, a better gut environment often translates into better brain health outcomes like better stress resilience. Here are just a few ways probiotic supplements work to resolve underlying gut issues and ultimately improve stress and other health problems:

• Increase the diversity of your bacterial community [14, 15, 16]
• Fight pathogens (harmful bugs) and their toxins [14, 15, 17, 18, 19]
• Promote a more rapid recovery from imbalanced gut organisms [14, 15]
• Modulate and promote a healthy immune system response in your gut [14, 15, 20, 21, 22]
• Reduce gut inflammation [14, 15, 16]
• Encourage the growth of good gut bacteria and other healthy microbes in your gut [14, 15, 20]
• Reduce leaky gut [14, 15, 23, 24, 25]
• Alter serotonin metabolism [16]

There’s ample evidence that shows that healing the gut with diet and probiotics help improve fatigue, anxiety, and depression. Here’s a chart summarizing the research on probiotics for stress: 

As you can see, the majority of this research suggests that the benefits of probiotics extend to many different populations with many different health conditions when it comes to reducing the symptoms of stress, including anxiety, depression, and cognitive dysfunction. It’s important to note that these improvements occurred independently of whether cortisol levels were changed. This reminds us that cortisol isn’t necessarily predictive of symptoms in stressed people and why cortisol testing is often unnecessary. 

Measuring salivary cortisol levels is often promoted in functional medicine as a way to assess stress levels and monitor improvement during treatment, but simply looking at cortisol may cause us to miss the mark as it doesn’t correlate well with symptoms [31].  In other words, a patient could have completely normal salivary cortisol levels and still be suffering. We always want to be careful to avoid chasing a certain healthcare lab marker over what we’re observing, and what our patients are telling us. The important point here is that patients can still experience positive benefits by taking probiotics for stress, even if cortisol levels remain unchanged. And our goal should always be symptom improvement and enhanced well-being, not necessarily movement in a lab value. 

I’m a fan of using subjective measures of stress, and many researchers use tools like the Perceived Stress Questionnaire (PSQ), which helps to measure:

• Fatigue
• Irritability, frustration, tensions, and general emotional dysregulation
• Loneliness
• Happiness
• Increased feelings of pressure and worry
• Feeling unsafe and judged 
• Dizziness
• Cognitive issues, like difficulty thinking
• Feeling overburdened with responsibility

Now that you know how probiotics work to modulate the stress response, let’s take a look at the probiotics for stress protocol I use in the clinic.

Probiotics for Stress Protocol

Probiotics are inexpensive, extremely safe, and very effective at improving the health of your gut microbiome, which is often an upstream cause of stress-related symptoms  [16, 20, 24, 25]. And probiotics also directly impact the stress response by modulating cortisol levels [2] . In the clinic, I use a triple therapy probiotic approach, which simply means we’re combining all three categories of probiotics:

• Lactobacillus/bifidobacterium blend (lactic acid producing bacteria like lactobacillus acidophilus, lactobacillus casei, lactobacillus rhamnosus, lactobacillus plantarum, lactobacillus helveticus, and/or bifidobacterium longum)
• Saccharomyces boulardii (a healthy fungus)
• Soil-based (spore-forming bacillus species)

You may see benefits by taking just one of these categories, but in my clinical experience, many people don’t seem to achieve balance in their microbiota with just one strain of probiotic. I have seen the best results with my patients who follow a protocol that includes probiotic strains from all three categories, so that’s why I recommend the triple therapy approach. 

And for many patients who have tried probiotics in the past without much success, this approach can make all the difference. High-quality research, including a meta-analysis, found that when mixtures of multiple categories of probiotics were compared with single strains of probiotics, the multi-strain probiotics were more effective at treating IBS [32, 33]. 

Here’s how to go about adding probiotics for stress:

• You can trial all three categories of probiotics together right from the start, but it’s also fine to start each one separately to get a good idea of how each category may affect you personally. 
• Plan to take the probiotics for 4–8 weeks and listen to your body. 
• If your symptoms are continuing to improve at the 4–8 week mark, stay on the probiotics. 
• Once you’ve reached a plateau in symptoms, stick with it for 2–3 more weeks, and then if you want to, you can start lowering the dose. Be mindful to pay close attention to your symptoms during this time. 
• If you notice things are starting to worsen, then you’ll probably want to resume the probiotics. 
• Continue this process of investigation and aim for the minimum effective dose for you.

If you’ve been experiencing high levels of stress, fatigue, difficulty sleeping, anxiety, depression, digestive symptoms, or any combination of these, it’s worth trying an intervention with probiotics. I want to make the point here that you don’t need a salivary cortisol test or other adrenal testing to confirm you’re stressed before starting probiotics. The best way to know whether or not probiotics will help you is to try them and listen to your body. Now let’s discuss some additional natural therapies for stress. 

Additional Natural Therapies for Stress

While probiotics for stress can be very effective, you’ll probably get the most health benefits when you target stress with a variety of nutrition and lifestyle measures. Here are a few to get you started:

• Anti-inflammatory diet. Improving your diet is one of the most impactful measures you can take to improve your gut microbiota and the health of your gut, which can help to normalize the stress response [34]. There’s no one perfect diet for everyone, so it’s important to find what works for your body. Overall, you’ll want to focus on whole, unprocessed foods. Some meal plan options include Paleo and low FODMAP.
• Stress management techniques. Mind-body therapies have been found to be highly effective in reducing IBS symptom severity [1]. I recommend adding at least one daily stress management practice to your routine to help keep stress levels in check. Some great options include yoga, meditation, deep breathing, Tai chi, and time in nature.
• Healthy exercise. Exercise is a healthy stressor, so if you’re in a stressed state, too much exercise can worsen stress and burnout. I recommend starting out with light activities like walking outside. If you’re feeling great, then start to increase based on your fitness level. Pay attention to the signs of overtraining, like poor sleep, chronic sore muscles, and fatigue after workouts though.

Probiotics Help to Combat Stress

Healing your gut is a powerful way to improve stress-related symptoms. Dysregulated stress hormones like cortisol, an altered stress response, fatigue, and anxiety can all be caused by an imbalance in your gut. Probiotics work to resolve those underlying issues, which will improve the stress response, as well as your feelings of stress, fatigue, and anxiety. Likewise, unmanaged stress can lead to gut issues like IBS by creating inflammation, dysbiosis, and leaky gut. 

Probiotics work in a variety of ways to resolve underlying gut issues and regulate cortisol levels, which helps in the modulation of the stress response. If you’re experiencing the symptoms of stress, a trial of probiotics may be very effective for improving your symptoms. You don’t need to test your stress hormones before starting probiotics, and you’ll likely get the most benefit from using the triple therapy probiotic approach. 

While you’ll likely feel the effects of probiotics alone, using natural therapies like diet, meditation, and exercise in combination with probiotics may be even more impactful. All these options work together to restore a healthy gut-stress connection, which will significantly improve your quality of life.  

If you’re struggling with stress and poor gut health, check out my step-by-step self-help guide in Healthy Gut, Healthy You. This protocol walks you through the foundational steps to healing your gut, which will, in turn, improve your stress resilience. If you’d like a more personalized plan, contact us at the Ruscio Institute for Functional Health.

The Ruscio Institute has developed a range of high-quality formulations to help our patients and audience. If you’re interested in learning more about these products, please click here. Note that there are many other options available, and we encourage you to research which products may be right for you.