Psychobiotic Explained

Psychobiotics is a term used in preliminary research to refer to live bacteria that, when ingested in appropriate amounts, might confer a mental health benefit by affecting microbiota of the host organism. Whether bacteria might play a role in the gut-brain axis is under research. A 2020 literature review suggests that the consumption of psychobiotics could be considered as a viable option to restore mental health^[1] although lacking randomized controlled trials on clear mental health outcomes in humans.^{[2] [3]}

Types

In experimental probiotic psychobiotics, the bacteria most commonly used are gram-positive bacteria, such as Bifidobacterium and Lactobacillus families, as these do not contain lipopolysaccharide chains, reducing the likelihood of an immunological response.^[4] Prebiotics are substances, such as fructans and oligosaccharides, that induce the growth or activity of beneficial microorganisms, such as bacteria on being fermented in the gut.^[5] Multiple bacterial species contained in a single probiotic broth is known as a polybiotic.^[6]

Research

A 2021 review showed that treating anxiety in young people with psychobiotics had no significant effect.^[7] There is a need for more diverse human studies, mainly because those that exist have contradictory outcomes.^{[2] [3] [7]}

Species

Several species of bacteria have been used in probiotic psychobiotic research:^[8]

• Lactobacillus helveticus
• Bifidobacterium longum
• Lactobacillus casei
• Lactobacillus plantarum
• Lactobacillus acidophilus
• Lactobacillus delbrueckii subsp. bulgaricus
• Bifidobacterium breve
• Bifidobacterium infantis
• Streptococcus salivarius
• Lactobacillus rhamnosus
• Lactobacillus gasseri

Further reading

• Book: The Psychobiotic Revolution. Random House US. Scott C.. Anderson. John F.. Cryan. Ted. Dinan. 17 December 2019. 1. 9781426219641.

Notes and References

1. Psychobiotics: Mechanisms of Action, Evaluation Methods and Effectiveness in Applications with Food Products . 2020 . 10.3390/nu12123896. 7767237 . free . Del Toro-Barbosa . M. . Hurtado-Romero . A. . Garcia-Amezquita . L. E. . García-Cayuela . T. . Nutrients . 12 . 12 . 3896 . 33352789 .
2. Romijn AR, Rucklidge JJ . Systematic review of evidence to support the theory of psychobiotics . Nutrition Reviews . 73 . 10 . 675–93 . October 2015 . 26370263 . 10.1093/nutrit/nuv025 . free .
3. Liu B, He Y, Wang M, Liu J, Ju Y, Zhang Y, Liu T, Li L, Li Q . Efficacy of probiotics on anxiety-A meta-analysis of randomized controlled trials . Depression and Anxiety . 35 . 10 . 935–45 . July 2018 . 29995348 . 10.1002/da.22811. 51615532 . free .
4. Sarkar A, Lehto SM, Harty S, Dinan TG, Cryan JF, Burnet PW . Psychobiotics and the Manipulation of Bacteria-Gut-Brain Signals . Trends in Neurosciences . 39 . 11 . 763–81 . November 2016 . 27793434 . 5102282 . 10.1016/j.tins.2016.09.002 .
5. Hutkins RW, Krumbeck JA, Bindels LB, Cani PD, Fahey G, Goh YJ, Hamaker B, Martens EC, Mills DA, Rastal RA, Vaughan E, Sanders ME . Prebiotics: why definitions matter . Current Opinion in Biotechnology . 37 . 1–7 . February 2016 . 26431716 . 4744122 . 10.1016/j.copbio.2015.09.001 .
6. Bambury A, Sandhu K, Cryan JF, Dinan TG . Finding the needle in the haystack: systematic identification of psychobiotics . British Journal of Pharmacology . 175 . 24 . 4430–38 . December 2018 . 29243233 . 6255950 . 10.1111/bph.14127 .
7. Cohen Kadosh. Kathrin. Basso. Melissa. Knytl. Paul. Johnstone. Nicola. Lau. Jennifer Y. F.. Gibson. Glenn R.. 2021-06-16. Psychobiotic interventions for anxiety in young people: a systematic review and meta-analysis, with youth consultation. Translational Psychiatry. en. 11. 1. 352 . 10.1038/s41398-021-01422-7. 2158-3188. 8206413. 34131108.
8. Dinan TG, Stanton C, Cryan JF . Psychobiotics: a novel class of psychotropic . Biological Psychiatry . 74 . 10 . 720–26 . November 2013 . 23759244 . 10.1016/j.biopsych.2013.05.001 . 40059439 .