There is a giant — and ever expanding — world of probiotics out there to choose from. The following is a a short list from the book The Psychobiotic Revolution along with some of their benefits.

Also for the lazy, I have included a quick start reference for your next trip to Whole Foods!

Quick Start Reference

Anxiety
Probio’Stick, L. helveticus, L. plantarum, B. breve, B. longum

Depression
B. bifidum, B. breve, B. longum + L. helveticus, L. acidophilus, L. brevis, L. casei, L. delbrueckii, L. plantarum, L. rhamnosus, L. salivarius, L. lactis, S. thermophilus

IBS
B. bifidum, B. infantis, B. animalis, B. lactis, L. plantarum, Mutaflor

Ulcerative colitis
F. prausnitzii, B. breve + galacto-oligosaccharide (GOS), VSL#3, L. plantarum, L. rhamnosus, L. reuteri ATCC 55730, L. delbrueckii + L. fermentum, Mutaflor

Crohn’s disease
S. boulardii, Mutaflor

Diarrhea
B. bifidum, B. infantis, B. longum, L. rhamnosus, S. thermophilus

Antibiotic-induced diarrhea
B. lactis, S. boulardii, L. rhamnosus, L. plantarum, L. casei

Bifidobacterium longum (R0175 & 1714) or Bifidobacterium infantis (35624)

B. longum inhibits pathogens in the large intestine, reducing inflammation and helping to prevent diarrhea. It also helps mitigate lactose intolerance and food allergies. Some research has shown that it can lower cholesterol and can act as an antioxidant. Via the neuroendocrine system and the vagus nerve, B. longum reduces anxiety and cortisol levels.3 Through its effects on hippocampal growth factors, it can reduce depression as well. It can also improve cognition, and so might be useful for healthy people who want to improve performance.4 Under stress, it can improve your coping skills. It has been tested on humans5 and the results track those found in mice and rats.

• In a clinical study, we tested whether psychobiotic consumption could affect the stress response and cognition in healthy volunteers. Our results indicate that consumption of B. longum 1714 reduces the perception of stress, reduces morning cortisol levels, and improves memory.6

• B. longum boosts the amount of available tryptophan, a precursor to serotonin, which can have an antidepressant effect. This is the same neurotransmitter involved with SSRIs. B. longum is now considered to be technically the same as B. infantis, and the strain numbered 35624 is known to be a potent anti-inflammatory. You may see it listed as either longum or infantis on an ingredient list.7 Along with L. helveticus, it is naturally found in yogurt, kefir, and sauerkraut.

Bifidobacterium breve (1205)

B. breve has shown results similar to B. longum, but with slight differences. It seems to have a greater influence on anxiety than depression.8 It prevents the growth of E. coli, as well as Candida albicans, the fungus behind yeast infections. Its strong antipathogen effect may explain why it helps in the fight against diarrhea, IBS, and allergies. It improves gut health in both premature babies9 and those born by cesarean delivery,10 often with a lifelong impact. In addition, B. breve has long been known to alleviate problems associated with antibiotics.11

• In our laboratory, we found that both B. longum and B. breve helped to lower anxiety in a mouse bred to be anxious. Whereas B. longum acted as an antidepressant, B. breve lowered anxiety. Both species compared well against the antidepressant escitalopram (marketed as Lexapro or Cipralex) to reduce anxiety and depression. In our lab B. longum reduces perception of stress and morning cortisol levels in healthy volunteers.

• These results also suggest that each bacterial strain has intrinsic effects and may be beneficially specific for a given disorder. These findings strengthen the role of gut microbiota supplementation as psychobiotic-based strategies for stress-related brain-gut axis disorders.12

Bifidobacterium animalis (DN 173 010, BB-12, Bi-07) or Bifidobacterium animalis lactis (HN019, DR10)

B. animalis, another member of the Bifido genera that includes the subspecies B. animalis lactis, has proven a benefit to people with ulcerative colitis.13 It has been shown to improve both constipation and diarrhea associated with irritable bowel syndrome (IBS).14 B. animalis is friendly with other psychobiotics, including various Bifido and Lacto species. It causes their numbers to increase, giving you extra bang for the buck.15 B. lactis has been shown to improve mood when used in combination with L. bulgaricus, S. thermophilus, and L. lactis.16

Bifidobacterium bifidum

If you were born vaginally, B. bifidum will be one of your oldest bacterial friends. Newborns typically pick it up as they pass through the birth canal. It competes with pathogens including E. coli and yeasts such as Candida and helps prevent diarrhea. B. bifidum in combination with L. acidophilus and L. casei (in capsule form) for eight weeks has been shown to help people with major depressive disorder.17

Lactobacillus acidophilus (ATCC 4356)

L. acidophilus is the most popular bacteria in probiotic and psychobiotic formulations. It has a long history of safety and is found in fermented foods such as yogurt, sauerkraut, and kefir. It helps to prevent diarrhea and is useful in treating small intestinal bacterial overgrowth (SIBO). It not only lowers inflammation but also increases opioid and cannabinoid receptors, acting as an analgesic and mitigating gut pain.18

L. acidophilus is a potent fighter against Campylobacter jejuni, a pathogen that causes gastroenteritis and anxiety. L. acidophilus outcompetes jejuni and prevents it from sticking to and infecting the cells lining your gut.19 This antipathogenic behavior is a major contributor to its antianxiety effect.

Lactobacillus delbrueckii (bulgaricus) or Lactobacillus helveticus (R0052 & NS8)

L. bulgaricus is found in yogurt and kefir and is often found with other Lacto and Bifido species in these products. It has been shown to improve mood when used in a mix with other milk fermenters. Because it ferments lactose, it can help with lactose intolerance. Human studies have shown it to improve immune function and to moderate the response to emotional stimuli. Recently, L. delbrueckii has been reclassified as L. helveticus.

L. helveticus is a popular addition to cheese cultures, as it inhibits bitter flavors. It has been shown to reduce blood pressure as well as depression and anxiety. Recent studies report that increasing the level of Lacto in the gut lowers the blood pressure of people with hypertension.20 Its main mode of action is to lower inflammation and enhance serotonin signaling. In animal models of liver disease, L. helveticus helps prevent anxiety and cognitive impairment.21 Studies have shown that L. helveticus can mitigate the inflammation and anxiety involved with eating a Western diet.22 Although most of these studies have been done in mice, human studies have shown that L. helveticus enhances nutrient absorption, removes allergens, and fights pathogens.23 Its use in cheesemaking ensures that it is safe for human consumption.

Lactobacillus rhamnosus (IMC 501, JB-1, GG)

L. rhamnosus has been found to be useful for treating peanut allergies, diarrhea, dermatitis, and obesity. It has been shown in animal studies to reduce both depression and anxiety, possibly by increasing levels of the neurotransmitter GABA. The effects depend on the vagus nerve, and if it is severed, the effects disappear.24 L. rhamnosus can alleviate obsessive-compulsive disorder (OCD) in mice. It lowers levels of corticosteroids, which reduces levels of stress, and it produces short-chain fatty acids, including butyrate, that both feed and heal the gut. Butyrate can also penetrate the BBB, where it acts as an antidepressant.

• In laboratory testing it was shown that regular treatment with L. rhamnosus induced region-dependent alterations in GABA throughout the brain in comparison with controls. Alterations in GABA expression are implicated in the “pathogenesis of anxiety and depression, which are highly comorbid with functional bowel disorders.

• Importantly, L. rhamnosus reduced stress-induced corticosterone and anxiety- and depression-related behavior. Moreover, the neurochemical and behavioral effects were not found when the vagus was severed, identifying the vagus as a major modulatory communication pathway between the gut bacteria and the brain.25

L. rhamnosus is found in yogurt, Parmigiano-Reggiano cheese, kefir, fermented sausage, and fermented soy cheese. Note: Use caution with this psychobiotic if you have an impaired immune system, such as what accompanies HIV or lupus, as it could trigger sepsis.

L. rhamnosus GG (LGG) is contained in products, including Culturelle, Nutramigen, LGG, and others. It is one of the best studied strains of L. rhamnosus and has been shown to be effective in treating IBS,26 a disease associated with depression and anxiety. However, in tests with healthy volunteers, it was not shown to reduce stress or improve cognitive performance.27

Lactobacillus reuteri

L. reuteri is one of the most ubiquitous species of gut bacteria, present across a wide spectrum of animals and always with a positive effect on health. In mice, it has been found to correct problems in pups born to mothers on a high-fat diet, including problems socializing.28

L. reuteri produces antibiotics against pathogenic bacteria, yeasts, and protozoans, making it a potent probiotic and an anti-inflammatory. It colonizes in the gut quickly. It improves skin tone, along with reproductive fitness, lowers inflammation, and increases oxytocin levels in both mice and humans.29 It increases levels of leptin (the satiety hormone) and decreases levels of ghrelin (the hunger hormone), potentially decreasing your caloric intake.

L. reuteri has been shown to reduce visceral pain, which can reduce pain-related anxiety. Interestingly, this deadening effect is similar whether the L. reuteri is killed or alive.30 L. reuteri can also lower levels of LDL (bad cholesterol) and inflammation, helping to prevent heart disease.31

Lactobacillus plantarum (299v, PS128)

L. plantarum is found in many fermented foods, including pickles, kimchi, brined olives, and sauerkraut—all great ways to consume this psychobiotic. It has been shown in humans to attenuate soy allergies and reduce inflammation. In animal studies it has been shown to enhance memory, even reducing age-related memory loss.32 Some popular products for bowel support contain only this species of bacteria.

L. plantarum strain PS128 competes with Clostridia and Enterococcus species, so it not only boosts Bifido levels, it also knocks down those potential pathogens.33 L. plantarum inhibits inflammation and has been shown to reduce gut pain in patients with IBS.34

Lactobacillus casei (Shirota, DN-114001, Immunita)

L. casei, like other Lacto species, is used in cheese- and yogurt-making and enjoys the company of L. acidophilus. It has been found to be useful in preventing antibiotic-induced diarrhea and C. diff infections, both of which are strongly associated with anxiety. When patients are on antibiotics, many doctors today will prescribe yogurt to help mitigate the inevitable damage of these drugs on the microbiota, and it’s thanks to the L. casei in the yogurt that it has beneficial effects. Studies in humans with depression showed an improvement in mood after 10 days of consuming yogurt containing L. casei.35

Patients with chronic fatigue syndrome had less anxiety and better gut health after eating L. casei.36 Interestingly, L. casei caused numbers of Bifido to increase, which likely contributed to the effect—an example of how many of the psychobiotics listed here can work as a team.

Lactobacillus paracasei (IMC 502)

L. paracasei is commonly found in fermented milk products and is common in probiotic mixes. It has been shown to lower levels of pain and intestinal distress caused by antibiotics and is a good adjunct when taking those drugs. In combination with L. rhamnosus, it has been shown to minimize the oxidative stress associated with intense physical activity.37 L. paracasei has also been shown to reduce the liver damage resulting from chronic alcohol consumption.38

Streptococcus thermophilus

S. thermophilus may not sound like a psychobiotic—after all, strep throat is caused by its cousin, S. pyogenes—but this species is a good gut citizen and has been used in fermented foods for centuries. S. thermophilus is a bacteria found in yogurt and kefir, and is often a fellow traveler with L. delbrueckii. They are synergistic: The S. thermophilus provides folic acid to Lactobacillus bulgaricus, thus improving the numbers of that psychobiotic. Women who consumed S. thermophilus in a yogurt formula showed less response to negative emotional stimulation, which is used as a rough determinant of anxiety.

Saccharomyces boulardii

Saccharomyces boulardii is the only psychobiotic on this list that isn’t a bacterium. It is instead a yeast and as such is not recommended for anyone with a compromised immune system or sensitivity to yeast. For others, however, this fungus has a long history of treating diarrhea. Given with antibiotics, it helps to reduce the chances of C. diff infection. Some studies have shown it to be effective with IBS and its attendant anxiety. It has also been shown to be effective in treating the two manifestations of IBD: ulcerative colitis and Crohn’s.39

References:

3. Premysl Bercik, Elena F. Verdu, Jane A. Foster, Joseph Macri, Murray Potter, Xiaxing Huang, Paul Malinowski, et al., “Chronic Gastrointestinal Inflammation Induces Anxiety-Like Behavior and Alters Central Nervous System Biochemistry in Mice,” Gastroenterology 139, no. 6 (December 2010): 2102–12.e1, doi:10.1053/j.gastro.2010.06.063

4. H. M. Savignac, M. Tramullas, B. Kiely, T. G. Dinan, and J. F. Cryan., “Bifidobacteria Modulate Cognitive Processes in an Anxious Mouse Strain,” Behavioural Brain Research 287 (2015): 59–72, doi:10.1016/j.bbr.2015.02.044.

5. Michaël Messaoudi, Robert Lalonde, Nicolas Violle, Hervé Javelot, Didier Desor, Amine Nejdi, Jean-François Bisson, et al., “Assessment of Psychotropic-Like Properties of a Probiotic Formulation (Lactobacillus helveticus R0052 and Bifidobacterium longum R0175) in Rats and Human Subjects,” British Journal of Nutrition 105, no. 5 (March 2011): 755–64, doi:10.1017/S0007114510004319.

6. A. P. Allen, W. Hutch, Y. E. Borre, P. J. Kennedy, A. Temko, G. Boylan, E. Murphy, J. F. Cryan, T. G. Dinan, and G. Clarke. “Bifidobacterium longum 1714 as a Translational Psychobiotic: Modulation of Stress, Electrophysiology and Neurocognition in Healthy Volunteers,” Translational Psychiatry 6, no. 11 (November 1, 2016): e939, doi:10.1038/tp.2016.191.

7. “Friedrich Altmann, Paul Kosma, Amy O’Callaghan, Sinead Leahy, Francesca Bottacini, Evelyn Molloy, Stephan Plattner, et al., “Genome Analysis and Characterisation of the Exopolysaccharide Produced by Bifidobacterium longum Subsp. longum 35624TM,” PLOS ONE 11, no. 9 (September 22, 2016): e0162983, doi:10.1371/journal.pone.0162983.

8. H. M. Savignac, B. Kiely, T. G. Dinan, and J. F. Cryan, “Bifidobacteria Exert Strain-Specific Effects on Stress-Related Behavior and Physiology in BALB/c Mice,” Neuro­gastroe­nterology and Motility: The Official Journal of the European Gastrointestinal Motility Society 26, no. 11 (November 2014): 1615–27, doi:10.1111/nmo.12427.

9. Yudong Li, Toshiaki Shimizu, Atsuto Hosaka, Noritsugu Kaneko, Yoshikazu Ohtsuka, and Yuichiro Yamashiro, “Effects of Bifidobacterium breve Supplementation on Intestinal Flora of Low Birth Weight Infants,” Pediatrics International: Official Journal of the Japan Pediatric Society 46, no. 5 (October 2004): 509–15, doi:10.1111/j.1442-200x.2004.01953.x.

10. Jian-jun Ren, Zhao Yu, Feng-Ling Yang, Dan Lv, Shi Hung, Jie Zhang, Ping Lin, Shi-Xi Liu, Nan Zhang, and Claus Bachert, “Effects of Bifidobacterium breve Feeding Strategy and Delivery Modes on Experimental Allergic Rhinitis Mice,” PloS One 10, no. 10 (2015): e0140018, doi:10.1371/journal.pone.0140018.

11. R. Fuller, “Probiotics in Human Medicine,” Gut 32, no. 4 (April 1991): 439–42.

12. “H. M. Savignac, B. Kiely, T. G. Dinan, and J. F. Cryan, “Bifidobacteria Exert Strain-Specific Effects on Stress-Related Behavior and Physiology in BALB/c Mice,” Neurog­astroen­terology and Motility: The Official Journal of the European Gastrointestinal Motility Society 26, no. 11 (November 2014): 1615–27, doi:10.1111/nmo.12427.

13. Yezaz A. Ghouri, David M Richards, Erik F Rahimi, Joseph T Krill, Katherine A Jelinek, and Andrew W DuPont, “Systematic Review of Randomized Controlled Trials of Probiotics, Prebiotics, and Synbiotics in Inflammatory Bowel Disease,” Clinical and Experimental Gastroenterology 7 (December 9, 2014): 473–87, doi:10.2147/CEG.S27530.

14. D. Guyonnet, O. Chassany, P. Ducrotte, C. Picard, M. Mouret, C. H. Mercier, and C. Matuchansky, “Effect of a Fermented Milk Containing Bifidobacterium animalis DN-173 010 on the Health-Related Quality of Life and Symptoms in Irritable Bowel Syndrome in Adults in Primary Care: A Multicentre, Randomized, Double-Blind, Controlled Trial,” Alimentary Pharmacology & Therapeutics 26, no. 3 (August 1, 2007): 475–86, doi:10.1111/j.1365-2036.2007.03362.x.

15. M. Ahmed, J. Prasad, H. Gill, L. Stevenson, and P. Gopal, “Impact of Consumption of Different Levels of Bifidobacterium lactis HN019 on the Intestinal Microflora of Elderly Human Subjects,” Journal of Nutrition, Health & Aging 11, no. 1 (February 2007): 26–31.

16. Ryan Rieder, Paul J. Wisniewski, Brandon L. Alderman, and Sara C. Campbell, “Microbes and Mental Health: A Review,” Brain, Behavior, and Immunity (January 25, 2017), doi:10.1016/j.bbi.2017.01.016.

17. “Ghodarz Akkasheh, Zahra Kashani-Poor, Maryam Tajabadi-Ebrahimi, Parvaneh Jafari, Hossein Akbari, Mohsen Taghizadeh, Mohammad Reza Memarzadeh, Zatollah Asemi, and Ahmad Esmaillzadeh, “Clinical and Metabolic Response to Probiotic Administration in Patients with Major Depressive Disorder: A Randomized, Double-Blind, Placebo-Controlled Trial,” Nutrition 32, no. 3 (March 2016): 315–20, doi:10.1016/j.nut.2015.09.003.

18. Christel Rousseaux, Xavier Thuru, Agathe Gelot, Nicolas Barnich, Christel Neut, Laurent Dubuquoy, Caroline Dubuquoy, et al., “Lactobacillus acidophilus Modulates Intestinal Pain and Induces Opioid and Cannabinoid Receptors,” Nature Medicine 13, no. 1 (January 2007): 35–37, doi:10.1038/nm1521.

19. Raffaella Campana, Sara Federici, Eleonora Ciandrini, and Wally Baffone, “Antagonistic Activity of Lactobacillus acidophilus ATCC 4356 on the Growth and Adhesion/Invasion Characteristics of Human Campylobacter jejuni,” Current Microbiology 64, no. 4 (April 2012): 371–78, doi:10.1007/s00284-012-0080-0.

20. Pedro A. Jose and Dominic Raj, “Gut Microbiota in Hypertension,” Current Opinion in Nephrology and Hypertension 24, no. 5 (September 2015): 403–09, doi:10.1097/MNH.0000000000000149.

21. Jia Luo, Tao Wang, Shan Liang, Xu Hu, Wei Li, and Feng Jin, “Ingestion of Lactobacillus Strain Reduces Anxiety and Improves Cognitive Function in the Hyperammonemia Rat,” Science China Life Sciences 57, no. 3 (March 2014): 327–35, doi:10.1007/s11427-014-4615-4.

22. Christina L. Ohland, Lisa Kish, Haley Bell, Aducio Thiesen, Naomi Hotte, Evelina Pankiv, and Karen L. Madsen. “Effects of Lactobacillus helveticus on Murine Behavior Are Dependent on Diet and Genotype and Correlate With Alterations in the Gut Microbiome,” Psychon­euroendo­crinology 38, no. 9 (September 2013): 1738–47, doi:10.1016/j.psyneuen.2013.02.008.

23. Valentina Taverniti and Simone Guglielmetti, “Health-Promoting Properties of Lactobacillus helveticus,” Frontiers in Microbiology 3 (2012): 392, doi:10.3389/fmicb.2012.00392.

24. Javier A. Bravo, Paul Forsythe, Marianne V. Chew, Emily Escaravage, Hélène M. Savignac, Timothy G. Dinan, John Bienenstock, and John F. Cryan, “Ingestion of Lactobacillus Strain Regulates Emotional Behavior and Central GABA Receptor Expression in a Mouse via the Vagus Nerve,” Proceedings of the National Academy of Sciences of the United States of America 108, no. 38 (September 20, 2011): 16050–55, doi:10.1073/pnas.1102999108.

25. Ibid.

26. Natalia Pedersen, Nynne Nyboe Andersen, Zsuzsanna Végh, Lisbeth Jensen, Dorit Vedel Ankersen, Maria Felding, Mette Hestetun Simonsen, Johan Burisch, and Pia Munkholm. “Ehealth: Low FODMAP Diet vs Lactobacillus rhamnosus GG in Irritable Bowel Syndrome,” World Journal of Gastroenterology 20, no. 43 (November 21, 2014): 16215, doi:10.3748/wjg.v20.i43.16215.

27. John R. Kelly, Andrew P. Allen, Andriy Temko, William Hutch, Paul J. Kennedy, Niloufar Farid, Eileen Murphy, et al., “Lost in Translation? The Potential Psychobiotic Lactobacillus rhamnosus (JB-1) Fails to Modulate Stress or Cognitive Performance in Healthy Male Subjects,” Brain, Behavior, and Immunity 61 (March 2017): 50–59, doi:10.1016/j.bbi.2016.11.018.

28. Shelly A. Buffington, Gonzalo Viana Di Prisco, Thomas A. Auchtung, Nadim J. Ajami, Joseph F. Petrosino, and Mauro Costa-Mattioli, “Microbial Reconstitution Reverses Maternal Diet-Induced Social and Synaptic Deficits in Offspring,” Cell 165, no. 7 (June 16, 2016): 1762–75, doi:10.1016/j.cell.2016.06.001.

29. S. E. Erdman and T. Poutahidis, “Probiotic ‘Glow of Health’: It’s More Than Skin Deep,” Beneficial Microbes 5, no. 2 (June 1, 2014): 109–19, doi:10.3920/BM2013.0042; Bernard J. Varian, Theofilos Poutahidis, Brett T. DiBenedictis, Tatiana Levkovich, Yassin Ibrahim, Eliska Didyk, Lana Shikhman, et al., “Microbial Lysate Upregulates Host Oxytocin,” Brain, Behavior, and Immunity 61 (March 2017): 36–49, doi:10.1016/j.bbi.2016.11.002.

30. T. Kamiya, L. Wang, P. Forsythe, G. Goettsche, Y. Mao, Y. Wang, G. Tougas, and J. Bienenstock. “Inhibitory Effects of Lactobacillus reuteri on Visceral Pain Induced by Colorectal Distension in Sprague-Dawley Rats,” Gut 55, no. 2 (February 2006): 191–96, doi:10.1136/gut.2005.070987.

31. Douglas B. DiRienzo, “Effect of Probiotics on Biomarkers of Cardiovascular Disease: Implications for Heart-Healthy Diets,” Nutrition Reviews 72, no. 1 (January 2014): 18–29, doi:10.1111/nure.12084.

32. J. J. Jeong, J. Y. Woo, K. A. Kim, M. J. Han, and D. H. Kim, “Lactobacillus pentosus Var. plantarum C29 Ameliorates Age-Dependent Memory Impairment in Fischer 344 Rats,” Letters in Applied Microbiology 60, no. 4 (April 2015): 307–14, doi:10.1111/lam.12393.

33. Kamini Ramiah, Carol A. van Reenen, and Leon M. T. Dicks, “Surface-Bound Proteins of Lactobacillus plantarum 423 That Contribute to Adhesion of Caco-2 Cells and Their Role in Competitive Exclusion and Displacement of Clostridium sporogenes and Enterococcus faecalis,” Research in Microbiology 159, no. 6 (July 2008): 470–75, doi:10.1016/j.resmic.2008.06.002.

34. K. Niedzielin, H. Kordecki, and B. Birkenfeld, “A Controlled, Double-Blind, Randomized Study on the Efficacy of Lactobacillus plantarum 299V in Patients with Irritable Bowel Syndrome,” European Journal of Gastroenterology & Hepatology 13, no. 10 (October 2001): 1143–47.

35. D. Benton, C. Williams, and A. Brown, “Impact of Consuming a Milk Drink Containing a Probiotic on Mood and Cognition,” European Journal of Clinical Nutrition 61, no. 3 (March 2007): 355–61, doi:10.1038/sj.ejcn.1602546.

36. A. Venket Rao, Alison C. Bested, Tracey M. Beaulne, Martin A. Katzman, Christina Iorio, John M. Berardi, and Alan C. Logan, “A Randomized, Double-Blind, Placebo-Controlled Pilot Study of a Probiotic in Emotional Symptoms of Chronic Fatigue Syndrome,” Gut Pathogens 1, no. 1 (March 19, 2009): 6, doi:10.1186/1757-4749-1-6

37. “Alison C. Bested, Alan C. Logan, and Eva M. Selhub, “Intestinal Microbiota, Probiotics and Mental Health: From Metchnikoff to Modern Advances: Part III—Convergence Toward Clinical Trials,” Gut Pathogens 5 (March 16, 2013): 4, doi:10.1186/1757-4749-5-4.

38. Noriko Komatsuzaki and Jun Shima, “Effects of Live Lactobacillus paracasei on Plasma Lipid Concentration in Rats Fed an Ethanol-Containing Diet,” Bioscience, Biotechnology, and Biochemistry 76, no. 2 (2012): 232–37, doi:10.1271/bbb.110390.

39. L. V. McFarland and P. Bernasconi, “Saccharomyces boulardii. A Review of an Innovative Biotherapeutic Agent,” Microbial Ecology in Health and Disease 6, no. 4 (January 1, 1993): 157–71, doi:10.3109/08910609309141323; Mario Guslandi, Gianni Mezzi, Massimo Sorghi, and Pier Alberto Testoni, “Saccharomyces boulardii in Maintenance Treatment of Crohn’s Disease,” Digestive Diseases and Sciences 45, no. 7 (July 1, 2000): 1462–64, doi:10.1023/A:1005588911207.

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