Inclusion Criteria:  Inclusion criteria for participation of drug-naïve patients is a confirmed PD diagnosis according to the Movement Disorder Society Clinical Diagnostic criteria. The healthy control group will consist of participants from the same age group with the same nutritional status (body mass index), as well as living in the same geographical area as the test group.  Exclusion Criteria:  unique diet plans, chronic bowel disease, any autoimmune disorder, acute infectious diseases, acute active inflammation, patient history positive for significant gastrointestinal surgical procedures and an active antibiotic, probiotic use.