Image by Tim Gouw

"Stress is the trash of modern life—if you don’t dispose of it properly, it will pile up and overtake your life."

 - Danzae Pace

Stress is ubiquitous in the world today. In 2020, up to 60% of Americans experienced daily stress, compared to a global average of 35% [1].

Stress: Balance is Vital

In certain situations, stress is a natural, physiological reaction. Specific hormones (such as adrenaline and cortisol) are released, creating a “fight or flight” reaction in our mind and body. Short-term stress can be healthy, boosting our focus and even survival. However, prolonged stress wears on our mental, emotional, and physical health.

IT Specialists Stress and Mood Study (2021)

Research Methods

Thirty-six high-tech industry professionals who reported high levels of stress (based on the Perceived Stress Scale, PSS) took psychobiotic PS128 (20 billion colony-forming units) daily for eight weeks. Before and after the trial, they self-assessed the following:
  • work and life stress (Job Stress Scale, Visual Analog Scale of Stress)
  • insomnia (Insomnia Severity Index)
  • anxiety (State and Trait Anxiety Index)
  • mood (Questionnaire for Emotional Trait and State)
  • depression (Patient Health Questionnaire)
  • overall health and life quality (Quality of Life Enjoyment and Satisfaction Questionnaire)
  • digestive health (Gastrointestinal Severity Index)
Stress biomarkers were also measured from participants’ saliva.


Perceived stress dropped >20% from baseline to endpoint
Saliva cortisol levels significantly decreased(p < 0.05)
  • Cortisol reduction significantly correlated with increased positive emotions
  • Cortisol reduction significantly correlated with improved sleep
Significant improvements seen in
Job stress

physical health


life quality




mood and depression

By relieving stress, PS128 may also benefit other stress-affected aspects of mental and physical health.

Risks of chronic stress

Chronic stress can lead to serious problems throughout our whole body.

Gut Microbiota and Autism

Gut-brain axis research has led to understanding of a direct, reciprocal influence that exists between GI tract microbiota and the CNS, including nervous system disorders such as autism, Parkinson’s, depression, and anxiety.


Regarding autism specifically, the gut microflora of individuals with an ASD is unique when compared to those without. Autism patients have a higher proportion of Firmicutes bacteria and relatively fewer Bacteroides. This has led to scientists asking whether gut microbe modification could lead to CNS improvements and neurological disorder treatments [3].

Treating Autism Via the Microbiome

Researcher Elaine Hsiao showed how this microbiome-gut-brain connection can influence ASD-like symptoms in mice [4]. Knowing that immune cells and inflammatory cytokines in the brain contribute to autism symptoms [5], Hsiao’s team mimicked an infection to activate the immune systems of pregnant mice. Soon after, the newborn pups exhibited both autism-like behaviors (anxiety, repetitive behaviors, and impaired social interaction) and GI tract symptoms (atypical, imbalanced gut microbes and intestinal permeability.)


Notably, after the pups were treated with Bacteroides from a human gut, their intestinal walls became more stable and blood data showed a decrease in a substance (4EPS) that induced their anxiety-like symptoms. Post-treatment, not only were the pups’ gut microbiomes more like those of a healthy mouse, but their symptoms of anxiety, repetitive behavior, and social impairment were also attenuated.


PS128 Can Help

Probiotics such as PS128 can similarly improve symptoms of ASD by enhancing the gut microbiome and regulating neural, endocrine, immune, and metabolic pathways. The psychobiotic may benefit those with ASD through its unique ability to modulate levels of dopamine and serotonin, and it has proven effective at lessening autism-like symptoms in mice [6][7].


Following the results of the NYMU study described above, additional experiments at Massachusetts General Hospital (USA) and Mackay Memorial Hospital (Taiwan) are also testing PS128’s effects on patients with autism.


[2] Liu, Y.-W.; Liong, M.T.; Chung, Y.-C.E.; Huang, H.-Y.; Peng, W.-S.; Cheng, Y.-F.; Lin, Y.-S.; Wu, Y.-Y.; Tsai, Y.-C. (2019.) Effects of Lactobacillus plantarum PS128 on Children with Autism Spectrum Disorder in Taiwan: A Randomized, Double-Blind, Placebo-Controlled Trial. Nutrients, 11, 820.

[3] Fattorusso, A., Di Genova, L., Dell'Isola, G. B., Mencaroni, E., & Esposito, S. (2019). Autism Spectrum Disorders and the Gut Microbiota. Nutrients, 11(3), 521.  

[4] Hsiao, E. Y., McBride, S. W., Hsien, S., Sharon, G., Hyde, E. R., McCue, T., … Mazmanian, S. K. (2013). Microbiota Modulate Behavioral and Physiological Abnormalities Associated with Neurodevelopmental Disorders. Cell, 155(7), 1451–1463.

[5] Herbert M. R. (2005). Autism: A brain disorder or a disorder that affects the brain? Clinical Neuropsychiatry, 2(6) ,354-79.

[6] Liu, W. H., Chuang, H. L., Huang, Y. T., Wu, C. C., Chou, G. T., Wang, S., & Tsai, Y. C. (2016). Alteration of behavior and monoamine levels attributable to Lactobacillus plantarum PS128 in germ-free mice. Behavioural brain research, 298(Pt B), 202–209.

[7] Liu, Y. W., Liu, W. H., Wu, C. C., Juan, Y. C., Wu, Y. C., Tsai, H. P., Wang, S., & Tsai, Y. C. (2016). Psychotropic effects of Lactobacillus plantarum PS128 in early life-stressed and naïve adult mice. Brain research, 1631, 1–12.