Probiotics/Anxiety

By Tami Tabatabai

Anxiety can be a debilitating state that can be broadly defined as excess worry or fear that doesn’t get better, and in fact, can get worse as time goes on.  Signs of anxiety include racing thoughts, lightheadedness, feelings of fear and/or uneasiness, heart palpitations, shortness of breath, uncontrollable obsessive thoughts, cold or sweaty hands and feet, and recurring flashbacks of past traumatic experiences that won’t go away. 

Gut/Brain Connection

Extensive research has shown that there is direct biochemical communication between the central nervous system (CNS) and the gastrointestinal (GI) tract, also known as the “gut-brain axis” (Wallace & Milev, 2017).  This bi-directional communication system involves the enteric nervous system, autonomic nervous system and the immune and neuroendocrine systems (Wallace & Milev, 2017).  The vagus nerve connects the brain to the GI tract, with the gut communicating more with the brain than the brain communicates to the gut (Dolan et al., 2016).  Mental health issues such as anxiety, autism and depression may stem from problems that arise in the gut (Dolan et al., 2016).

The lining of the GI tract is comprised of a complex ecosystem of around 100 trillion microorganisms known as the microbiome that work tirelessly to maintain GI function, and is influenced by the diet, genetics, sex, age and stress (Wallace & Milev, 2017).  Evidence has shown that the GI lining is susceptible to permeability from psychological stress and now, evidence is mounting that indicates that the microbiome also has an influence on modulating emotions (Wallace & Milev, 2017).  Pathogens in the gut can communicate with the CNS and in doing so, can influence behaviors that are associated with anxiety and emotion (Rao et al., 2009).

Probiotics

Probiotics are living bacteria that can provide therapeutic benefits for many imbalances in the GI tract.  Another benefit of probiotics is the ability to alter the enteric nervous system (Dolan et al., 2016), a division of the automatic nervous system (ANS), which resides in the gut.  Studies have consistently shown that consuming probiotics on a daily basis may improve cognitive, anxiety and mood symptoms, with the most significant effect being on anxiety symptoms (Wallace & Milev, 2017).

Treating Anxiety with Probiotics

In treating anxiety symptoms with probiotics, strains such as Lactobacillus casei Shirota (LcS) was found to significantly reduce Beck Anxiety Inventory (BAI) scores among patients that consumed the LcS bacteria (Rao et al., 2009).  Messaoudi et al. found that by consuming a combination of Lactobacillus helveticus R0052 and Bifidobacterium longum R0175 for 30 days, anxiety related behaviors that were measured by the Hospital Anxiety and Depression Scale (HADS) were reduced (2011). 

The most beneficial effects with respect to mental health were found in the Lactobacillus and Bifidobacterium strains (Wallace & Milev, 2017).   A systematic review of the effect of probiotics on the CNS, found that positive results in reducing anxious behavior were found when using single strains of Bifidobacterium longum and Lactobacillus helveticus, as well as multi-strain combinations of B. longum and L. helveticus and also L. helveticus and L. rhamnosus (Wang, Lee, Braun & Enck, 2016).  The B. longum and L. helveticus bacterium were found to have a direct effect on the gut-brain axis (Wallace & Milev, 2017).

Given the research, addressing and modulating gut microbiota with probiotics may be a successful approach to also preventing and treating anxiety symptoms and disorders. 

References:

Dolan, K., Finley, H., Burns, C., Gasta, M., Gossard, C., Parker, E., . . . Lipski, L. (2016). Probiotics and Disease: A Comprehensive Summary – Part 1, Mental and Neurological Health. Integrative Medicine. 15:5. Retrieved from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5145013/

Messaoudi, M., Violle, N., Bisson, JF, Desor, D., Javelot, H. & Rougeot, C. (2011). Beneficial psychological effects of a probiotic formulation (Lactobacillus helveticus R0052 and Bifodobacterium longum R0175) in healthy human volunteers. Gut Microbes. 2:4 (256-261). Retrieved from https://www.tandfonline.com/doi/abs/10.4161/gmic.2.4.16108

Rao, A.V., Bested, A.C., Beaulne, T.M., Katzman, M.A., Iorio, C., Berardi, J.M. & Logan, A.C. (2009). A randomized, double-blind, placebo-controlled pilot study of a probiotic in emotional symptoms of chronic fatigue syndrome. Gut Pathogens. 1:6. Retrieved from https://gutpathogens.biomedcentral.com/articles/10.1186/1757-4749-1-6

Wallace, C.J.K. & Milev, R. (2017). The effects of probiotics on depressive symptoms in humans: a systematic review. Annals of General Psychiatry. 16:14. Retrieved from https://annals-general-psychiatry.biomedcentral.com/articles/10.1186/s12991-017-0138-2

Wang, H., Lee, I., Braun, C. & Enck, P. (2016). Effect of Probiotics on Central Nervous System in Animals and Humans: A Systematic Review. Journal of Neurogastroenterology and Motility. 22:4. Retrieved from http://www.jnmjournal.org/journal/view.html?doi=10.5056/jnm16018