Probiotics for Stress

Over 20% of American adults experience some sort of mental health challenge. Even those who don’t have a diagnosed mental health disorder may be impacted by stress, which can alter their mood. For some, probiotics have been shown to ease stress and anxiety. Here’s how. 

Can Probiotics Help Stress, Anxiety & Mood?

In life, there are plenty of factors that contribute to stress and anxiety. Most of them are out of your control. You might have psychological stress during common life changes. You might be picking up the slack at work because someone left your department. Your kids may be involved in a series of new activities, and you’re figuring out how to adjust your schedule. Events like marriage or a new baby can also cause added stress in your life. 

You might also have anticipatory stress that comes when you’re focused on something you have to do in the future. This is common if you’re preparing for a job interview or big presentation or need to have a serious conversation with someone in your life. 

Stress and anxiety are a common part of the human experience. If you’re one of about 6.8 million Americans suffering from an anxiety disorder, it's likely that your brain chemistry makes you prone to stress and anxiety.  

Some people experiencing these mood shifts find that taking probiotics for stress helps them feel better. A meta-analysis study in 2020 showed that probiotics may reduce the behavioral symptoms of people experiencing depression and could help make treatments more effective. This is because the body is made of interconnected systems, and there is a strong connection between the brain and the digestive tract. 

Researchers call the connection between intestinal function and emotional and cognitive behaviors the gut-brain axis. In the past decade, the connection between thriving gut flora and mental health has become more clear. When you’re stressed, hormones including cortisol can throw off the balance of good bacteria in your gut. On the other hand, poor gut health can alter neurotransmitter signals to the brain, leading to more stress and anxiety. 

Many probiotics can help your body fight off bad bacteria in your gut, restoring your digestive tract back to normal. Only a few probiotics, however, appear to be able to influence the levels of key neurotransmitters like serotonin in the bloodstream and/or in the brain. It is these probiotics, sometimes called psychobiotics, that may be helpful for anxiety, depression, and/or stress.

Which Probiotics Are Researched for Stress & Anxiety?

Clinically studied probiotics for stress

Many researchers are working on clinical studies to investigate psychobiotics for effects of stress, due to the prevalence of mental health issues in today’s world. Psychobiotics are probiotics that have a neurological or mental health benefit, and may or may not help the gut. 

Many studies on probiotics for stress are conducted like other medical clinical studies. Participants have to meet certain inclusion criteria, and a representative sample of the population is then recruited. In the most trustworthy studies (randomized controlled trials, or RCTs), scientists give some participants a placebo so their symptoms can be studied alongside participants taking probiotics. 

Here is a breakdown of some of the probiotics being studied for their potential impacts on stress and anxiety. 


These are two well-studied genera of bacteria that can be found in the human lower intestine and are also well represented in commercially available probiotics. Lactobacillus probiotics are usually abbreviated L. followed by the name of their species, for example, while Bifidobacterium is abbreviated with a B

Many Lactobacillus species are able to ferment sugars such as glucose and the milk sugar lactose to lactic acid. This fermentation action combined with rennet produces cheese curds, and Lactobacillus can continue to ferment additional lactose to produce the distinctive flavors of aged cheeses. Other Lactobacillus species are used to make cultured dairy products like yogurt and kefir.

A few neurologically active Lactobacillus species have been studied, and are available commercially. L. rhamnosus, L. casei and L. plantarum strains are of particular interest for their effects on stress and anxiety, as detailed in the next section.

Bifidobacterium is another group of “good” bacteria that helps you digest carbohydrates and plays a role in fighting off "bad" bacteria. Scientists have conducted clinical studies showing promising results from taking certain Bifidobacterium probiotics for impacting multiple health concerns ranging from irritable bowel syndrome (IBS) to lung infections and even stress and anxiety.

Which Probiotics Are Best for Stress & Mood?

Probiotics are one kind of supplement that is useful for stress and mood - photo of woman's open hand holding several different kinds of capsules and tablets

Psychological stress can alter your mental health, but thankfully, certain probiotics may be able to take the edge off your stress. Studies have shown how some of the probiotics mentioned above, plus a few others, can help regulate stress and anxiety not just in animals, but also in humans.

If you’re interested in improving your gut-brain axis and getting your overall gut health on track, look for probiotic products that incorporate these species:

B. longum

In multiple studies, B. longum was shown to have a positive impact on stress and anxiety. One strain of B. longum also helps your body control its cortisol level, a hormone produced when you’re under stress and anxiety. 

Researchers conducted a clinical study to determine how B. longum impacts brain function during stress through its relationship to the gut-brain axis. The study found that probiotics have an impact on the brain when subjects are performing emotional tasks. Thus, B. longum may be helpful in impacting your brain's ability to process emotions.

B. infantis

Another probiotic strain in the Bifidobacterium phylum, B. infantis is one of the probiotics that can interact with the nervous system through the gut-brain axis. Chronic stress can disrupt this balance, making it hard for your body to return to normal, which leads to a stress loop.

B. infantis helps break this loop, letting your body return to normal so your brain stops sending signals that increase inflammation within your body. As a result, taking this probiotic may reduce feelings of anxiety and stress that your body is signaling.

Lactobacillus casei

L. casei strain Shirota has been shown to reduce the body’s everyday reaction to stress. In one study, for instance, medical students were given the probiotic before taking exams, and various stress markers were measured, including anxiety scores and how much cortisol was present in their saliva. After taking the probiotic, analysts saw a reduction in cortisol levels. Additionally, many students reported lowered test anxiety and accompanying symptoms related to stress. 

Thus, taking L. casei strain Shirota may be a helpful way of reducing stress and improving mood regulation.

L. rhamnosus

L. rhamnosus is a common species found in psychobiotic formulas. In a clinical studyL. rhamnosus strain CNCM I-3690 helped students reduce their perceived stress during a stressful public speaking event. This gut-brain signaling effect of the probiotic was independent of a gut-health benefit that was also measured in the study. This suggests that L. rhamnosus CNCM I-3690 helped the students deal with stress not by improving their gut health, but by affecting their psychological stress by a neurological mechanism.

L. plantarum

L. plantarum is a species of the Lactobacillus genus, and strains of this species are common probiotics in supplements for mood and stress. In a placebo-controlled study, L. plantarum P8 helped people with stress and anxiety improve their mood. It also boosted their memory.

L. plantarum PS128 is another well-studied psychobiotic strain with neurological health benefits in people. It is commercially available as Neuralli, a non-drug therapy that addresses distinct nutritional requirements for gut microbiome to brain signaling in ASD, PD, and anxiety/depression that cannot be addressed by diet alone. 

Probiotics & Ashwagandha 

Some probiotic supplements for mood and stress also include ashwagandha, which is used in herbal wellness medicine. Ashwagandha has anti-inflammatory and antioxidant properties, which make it a good match for stress-relieving probiotics. 

Ashwagandha is known as an adaptogen, a type of natural product that can help you better adapt to stress. In one study, this root was shown to lower cortisol, which helps reduce stress-related symptoms. Taking a probiotic with ashwagandha may help you feel better when you’re stressed out. 

How Quickly Can You Improve Anxiety with Probiotics?

Two older men at an outdoor restaurant. One is holding a cup of coffee, and they are smiling at something on the smartphone that the second man is holding up.

Like other treatments for stress and anxiety, probiotics can take some time to kick in. Depending on your overall health, it may take longer for the probiotics to restore a healthy gut environment in your digestive tract and get you back to normal. 

There is no set time frame for probiotics to start working. It could take weeks for some people and months for others. It also depends on what kind of probiotic supplements you’re taking. You may notice other health benefits, such as better “regularity”, before you start seeing shifts in your stress and anxiety. Consider how long anxiety has been part of your life; it may take some time to reduce it. However, if you don’t notice an improvement within one to three months, try another probiotic. 

To help your probiotics to work more effectively, make sure you’re using probiotics that are formulated to aid with stress and anxiety, and pay attention to the recommended dosage. You should also check the expiration date of your probiotic supplements to ensure their efficacy. 

You can also try adding prebiotic foods to your regimen. Prebiotic fibers act as “food” for probiotics in your gut, helping them flourish. 

How Probiotics Work

Probiotics can help with inflammation. Photo of a seated man's legs - he is wearing shorts and holding one knee as if it hurts.

There are a variety of ways in which probiotics can help you manage your stress and anxiety. Here are some of the benefits of probiotics and how they work to help you combat stress.  

Reduce Inflammation

Inflammation is an immune response that helps our bodies attack invasive pathogens and clear out damaged cells. General signs of inflammation are redness, swelling, bruising, and pain of the affected area. Once the invasive pathogens are cleared or the damaged tissues are repaired, an acute inflammation response will stop. 

However, sometimes the inflammation continues even though it is no longer needed. This is called chronic inflammation, and it can lead to damage to the host tissues. Chronic inflammation is observed in obesity, diabetes, cardiovascular diseases, and aging. 

Interestingly, there is evidence of inflammation contributing to symptoms of anxiety and depression. This suggests that combating inflammation might help with stress and anxiety for some people.

Some probiotic strains are reported to have anti-inflammatory activity. The probiotics can interact with the immune system and help to reduce inflammatory responses therefore contributing to prevent further damages to the host.

Promote Heart Health

Probiotic supplements don't only help your brain – they can also benefit your heart. Many probiotic strains help lower low-density lipoprotein (LDL) cholesterol, which is known as “bad” cholesterol. Certain probiotics also help lower your blood pressure and regulate your blood glucose, processes that help keep your heart healthy. 

Chronic stress and anxiety can raise your blood pressure, causing increased strain on your heart. If you’re taking a probiotic, it can help combat this side effect of stress. 

Improve Sleep

Sleep disturbances are a common side effect of and contributor to stress and anxiety. Probiotics help your body produce more serotonin and other neurotransmitters, and they help disrupt a chronic stress response by regulating your gut-brain axis. All of these factors can help you sleep more soundly with better quality. You won’t wake up tired, which also boosts your mood. 

How To Take a Probiotic

A person is spooning plain yogurt from a glass jar

Now that you know how probiotics can help you regulate stress and anxiety, the next step is to find the right one for you. You can find probiotic species in common foods like yogurt and cheese. However, these foods likely do not have high concentrations of the types of probiotics that are most effective for ameliorating stress and anxiety. A specially formulated probiotic supplement is typically a better choice.

Probiotic supplements and medical foods come in a diversity of forms. Some are in capsules, while others come as powders that you can mix with water or cold food. Whichever supplement you choose, store it according to the label to ensure it retains its effectiveness. 

If you have a powder supplement, you can mix it with cool or room temperature water, yogurt, or another food. If the water’s too hot, it could kill your probiotics. Don’t eat or drink anything hot immediately after you take it.

If your probiotic needs to be stored in the refrigerator, you may find that you need help remembering to take it. Setting a reminder on your phone or leaving a reminder object with your other supplements & medications or by your toothbrush may help.

Find the Right Probiotic Supplement for You

Multiple clinical studies have shown that certain probiotics can help improve your mood, particularly if you experience stress and anxiety. Look for a product that’s specifically formulated for mood regulation, as it is most likely to have the most effective probiotic strains for reducing stress and anxiety. 

Once you start taking your probiotics, you may experience other health benefits like improved immunity, better heart health, and a well-balanced digestive tract. 

Pick a probiotic supplement that works for your lifestyle. If you need to grab and go, choose a capsule. Otherwise, opt for a powder and mix it into cool or room-temperature water. If you have trouble swallowing pills or prefer a powder, you can open up your capsules and mix their contents into water or other cold liquids and foods.

Anyone who experiences stress and anxiety knows how it impacts daily life. A probiotic like Neuralli may be a simple way to help you manage your mental health and feel better. 


Post a Comment!