Probiotics for Inflammation in Pediatric Chronic Pain

To examine benefits of a probiotic for youth with chronic pain and a Body Mass Index \>=85th percentile.

Inclusion Criteria: 1. Male or female biological sex 2. 13-17 years of age 3. Body Mass Index ≥85th percentile for sex and age Exclusion Criteria: 1. Probiotic (or prebiotic) supplement use or antibiotic use within the past month 2. Chronic inflammatory or autoimmune disease with the exception of well-controlled hypothyroidism or intermittent or mild persistent asthma not requiring the use of daily inhaled steroids 3. Patients who have had a poor response to blood draw or immunizations in the past 4. Chronic use of medications known to alter gastrointestinal function or inflammation (e.g. metformin, non-steroidal anti-inflammatory medications) 5. Any condition that, in the investigator's opinion, may compromise study participation or may confound the interpretation of the study results 6. Use of illicit drugs 7. Females who are pregnant or lactating