Cognitive and Biological Responses in Stress

Inclusion criteria

• Caucasian
• Female
• 18-45 years of age
• For the high perceived stress group: a PSS score of 15 or higher and a STAI-S of 39 or higher
• For the low perceived stress group: a PSS score of 8 or lower and a STAI-S score of 24 or lower

Exclusion criteria

• Any ongoing major medical, psychological, or psychiatric conditions and recent changes (3mo) in the use of psychoactive medications or other medications that interfere with the measured outcomes.
• Medical conditions such as current neurological, cardiovascular, hepatic, renal, autoimmune diseases, diabetes, or cancer. This includes having a current or past within 1 year diagnosis of GI disorders, including but not limited to IBS, IBD, Celiac, or other nutritional deficiency/disease, current eating disorder, or past weight loss surgery.
• Psychological conditions such as anxiety and depression (I.e., without history of Diagnostic and Statistical Manual (DSM-4) psychiatric diagnosis.
• Prior/Concomitant Therapy (e.g., Recent changes in the use of psychoactive medications or other medications that interfere with the measured outcomes, as determined by the PI).
• Subject involved in any other clinical study within the preceding month or in the exclusion period after another clinical study.
• Positive test for COVID-19 infection in the past month or if presenting symptoms of COVID-19 infection in the past 2 weeks.

Diet:

• Participant who changes her dietary habits within the preceding 4 weeks.
• Participants on probiotics will be asked to wait 1 month before enrollment in the study.
• Participant with an eating disorder.
• Participant with special medicated diet (e.g., for obesity, anorexia, metabolic pathology).
• Participant under artificial nutrition in the last 1 month.
• Participant planning to modify her dietary habits during the course of the study.

Other Exclusions:

• Pregnant women or women planning to become pregnant during the study; breast-feeding women based on the interview at screen (Visit 1) and the urine test on day of stress test (Visit 2).
• Smoker with a moderate to high level of dependence to nicotine (e.g., more than 1/2 a pack of cigarettes a day).
• Participant consuming regularly more than 3 units of alcohol per day (1 unit = 10mL or 8g).
• Participants not able to answer questionnaires by writing, whatever the reason.
• Participant with loos of liberty, by administrative or judicial decision.
• Participant who is major but with a legal guardian.
• Participant on antibiotics will be asked to wait 3 months before enrollment in the study.

Medications not Authorized:

• Opiates/Narcotics
• Chronic/Daily use of analgesics
• Anti-seizure meds
• Antidepressants (5HT3's / Tricyclics etc.) are allowed as long as it's been a stable dose for 3 months
• Medications for ADD/ADHD (I.e., Adderall)
• Any medication for appetite suppression
• Chronic use of laxative/antidiarrheals/medications affecting GI motility
• Insulin
• Bile acid sequestrants
• Use of centrally acting medications that will interfere with CNS testing