Psychobiotics is a term researchers use to describe regular probiotics when studying their potential effects on mental health. While probiotics are commonly associated with digestive health, some research suggests they may also benefit mental health. The gut-brain connection has become a focal point of scientific investigation and highlights the influence of the gut on overall well-being.
Psychobiotics is a word used by researchers referring to probiotics and their potential effects on mental health.
Gut bacteria can influence neurotransmitter production and potentially impact mental well-being.
Probiotics may help in conjunction with prescribed therapy but are likely ineffective on their own for treating mental health conditions.
Consult a healthcare provider before starting a probiotic supplement.
What are psychobiotics?
Psychobiotics are the same as probiotics. Probiotics are living microorganisms that help with digestion and normal bowel function. The difference is that researchers use the term “psychobiotics” when studying mental health or psychological outcomes in connection with probiotics.
Probiotics are also known as gut microbiota — the “good” or “friendly” bacteria that live in your digestive system. They can be obtained or enhanced through dietary supplements or certain foods, such as yogurt and fermented vegetables.
You may have heard that probiotics can be beneficial for gut health, but recent scientific evidence suggests that multiple different species of bacteria — such as Lactobacillus and Bifidobacterium — can also impact brain health. The specific bacterial strains beneficial for mental health are still being studied, and the quality and composition of probiotic supplements can vary significantly.
The gut-brain-microbiome connection
Ever get hangry? Or have “butterflies in your stomach” when you’re excited or a bellyache when you’re upset? These are just a few examples of the powerful link between the brain and the digestive tract. The trillions of microorganisms within and on our bodies, collectively known as the microbiome, play a vital role in regulating gut-brain function. This connection suggests that gut bacteria can influence neurotransmitter production and potentially impact mental well-being.
Also known as the gut-brain axis, the gut-brain connection is supported by the presence of a large number of nerves in the gut, including the vagus nerve, which connects the gut and the brain. The gut contains a significant amount of nerve activity, including the production of neurotransmitters like serotonin, dopamine, and GABA, which are crucial for mental health:
- Serotonin. Regulates mood, sleep, hunger, memory, and numerous other functions.
- Dopamine. Supports movement, motivation, and attention, and allows you to feel pleasure and satisfaction.
- GABA (gamma-aminobutyric acid). Inhibits cell signaling, essential to regulating sleep, anxiety, fear, and more.
An imbalance of microbes growing in the gastrointestinal (GI) tract — known as dysbiosis — shows how vital the microbiota-gut-brain axis is for overall health. Neurological symptoms, such as pain, often accompany dysbiosis. Also, some types of bacteria cause inflammation and harm to the GI tract, potentially causing wider danger to the body as a whole.
Further, scientific evidence points to an impaired gut-brain connection in individuals with mental health conditions. For instance, altered microbiota has been shown to occur in some individuals with schizophrenia. This can lead to an unfavorable overgrowth of yeast species, resulting in symptoms of dyspepsia (such as heartburn, stomach pain, nausea, or bloating). Dealing with these discomforts can contribute to worsening physical and mental health overall.
Early psychobiotic research focused on probiotic use and behavior in animal models. A 2011 study reported neurochemical and behavioral responses in mice given a probiotic supplement containing Lactobacillus. The researchers observed changes in the gut microbiota of the mice as well as stabilization of neurotransmitter levels in certain areas of the brain. They also observed that mice who received probiotics experienced fewer signs of anxiety or depression following a stress test.
A 2016 clinical study investigated the potential role of psychobiotics in Alzheimer’s disease. In this study, participants received milk containing a mixture of probiotics (Lactobacillus and Bifidobacterium) or plain milk for 12 weeks. While no improvement was seen in the biomarkers of disease progression, cognitive function was improved in those who received the probiotic milk.
More recent studies in psychobiotics for anxiety and depression have revealed potential benefits. A meta-analysis of psychobiotic trials totaling nearly 700 patients found the use of probiotics was associated with improved depression and anxiety scores. While the analysis showed little improvement in anxiety symptoms, psychobiotics were linked to some symptom improvement in patients with depression alone.
A recent clinical study of 135 people examined psychobiotic effects on several aspects of mental health. The study participants received probiotics (Lactobacillus + Bifidobacterium) or a placebo for four weeks. The investigators assessed the quality of life, emotional regulation, anxiety, and well-being. They also collected information on lifestyle changes linked to mental health, such as adequate sleep and limiting stressors. The results showed that psychobiotics alone did not correlate with improvement in mental health. However, when psychobiotics were combined with lifestyle changes, the researchers observed improvements in mental health.
Research points to a potential adjunct role for probiotics/psychobiotics in mental health. This means that probiotics may help, but they are not likely effective on their own for improving mental health. Probiotic supplements do not replace proven interventions such as healthy lifestyle changes, psychotherapy, cognitive behavioral therapy, or medication. More research is necessary to understand the mechanism and role of psychobiotics in mental healthcare.
Are psychobiotics right for me?
Probiotic supplements are generally safe for most people. Some exceptions exist, and infections can be a side effect of probiotics/psychobiotics, especially for those with a weakened immune system.
Keep in mind that the Food and Drug Administration (FDA) does not approve the safety and effectiveness of any dietary supplement, including probiotics. However, quality organizations independently validate the quality of supplements to help prevent contamination. When looking for high-quality supplements, check for a product verified by one of these organizations. Talk to a healthcare provider or pharmacist for help choosing a probiotic.
How to take psychobiotics
There isn’t a distinct type or dosage of probiotics that defines psychobiotics. Likewise, there isn’t a clear answer on whether it is better to obtain probiotics/psychobiotics from supplements or your diet. Studies also vary on the dose and duration of therapy.
In general, the minimum dose for probiotics is 1 billion colony-forming units (CFU) per day. Be sure to follow the instructions for dosing and storage on the probiotic product label. If you have questions about probiotics or dietary changes for gut health, talk to a healthcare provider for personalized advice.
- Physiological reviews. The Microbiota-Gut-Brain Axis.
- Nutrients. Psychobiotic effects on anxiety are modulated by lifestyle behaviors: A randomized placebo-controlled trial on healthy adults.
- Molecules. The Role of Probiotics and Their Metabolites in the Treatment of Depression.
- Gut. Gut microbiome and health: mechanistic insights.
- Proceedings of the National Academy of Sciences of the United States of America. Ingestion of Lactobacillus strain regulates emotional behavior and central GABA receptor expression in a mouse via the vagus nerve.
Show all references
- Frontiers in aging neuroscience. Effect of Probiotic Supplementation on Cognitive Function and Metabolic Status in Alzheimer's Disease: A Randomized, Double-Blind and Controlled Trial.
- Frontiers in neurology. Effects of Probiotics on Depressive or Anxiety Variables in Healthy Participants Under Stress Conditions or With a Depressive or Anxiety Diagnosis: A Meta-Analysis of Randomized Controlled Trials.
- Michigan State University Center for Research on Ingredient Safety. Probiotics & Prebiotics - Ingredient Safety.
- National Center for Complementary and Integrative Health. 5 Things To Know About Probiotics.