Probiotic Intervention Study for Obesity and Food Addiction

Inclusion Criteria: * Ages 18-50 * BMI 25-40 * Male and Female * Not Pregnant or Nursing Exclusion Criteria: * Co-morbidities including but not limited to: * Type 1 (insulin dependent) diabetes * vascular disease * drastic weight loss (more than 10lbs over the preceding 2months) * frequent strenuous exercise (i.e. marathon runners/heavy weight lifting) * abdominal surgeries including weight loss surgery or partial/complete resection of stomach or bowel * untreated thyroid disease * neurological disease * Major medical condition the PI/MD feels would put the subject at risk or interfere with data collection. * Chronic pain * Diagnosed DSM IV active psychiatric illness including eating disorders. Must not be active or present for at least 2 years. Participants with a positive endorsement on the MINI+ will be excluded. * Using medications known to affect hunger/satiety/appetite * Pregnant, lactating, postpartum less than 6months. * Women of childbearing potential who are not practicing birth control or are planning to get pregnant during the study. * Use of oral/IV antibiotics within the last 3 months * Use of probiotics in the last 3 months. * Heavy use of alcohol and drugs will be determined by a positive endorsement on the MINI+. If the MINI+ is positive for alcohol or drug dependence or abuse, the participant will be excluded. In regards to tobacco use, participants will be excluded if they smoke more than 1/2 pack per day. * Cannabis use will not be exclusionary. If the MINI+ is positive for drug dependence or abuse, the participant will be excluded. * Significant change in usual diet and/or weight loss of more than 10lbs in the last 2 months. * Anyone taking medicines on the medication exclusion list. * Non-English Speakers (due to the use of validated questionnaires and limited availability of translated copies, participants must be fluent in English so that they will be able to read and follow directions easily. * Maintenance pharmacotherapies will not be exclusionary so long as they have been on a stable dose for 6months. * Body weight at enrollment greater than 400lbs. * Exclude from Optional MRI if: participant is unable to safely participate in the MRI (claustrophobia, presence of devices affected by MRI such as pacemakers, neurostimulators, metallic foreign bodies, etc.).