Inclusion Criteria:  Willing to provide informed consent Willing to comply with all study procedures and be available for the duration of the study Has pathologically confirmed multiple myeloma, Non-Hodgkin lymphoma (DLBCL, mantle cell lymphoma, follicular lymphoma, or peripheral T-cell lymphoma), or Hodgkin lymphoma as determined on medical record review per standard of care transplant procedures (no tissue required for study) Meeting a standard-of-care indication for autologous stem cell transplantation for the above diseases as determined by the investigator Adult Individuals (male or female) at least 19 years of age Meeting indications and recommended for first autologous stem cell transplantation by investigator  Exclusion Criteria:  History of bariatric surgery (i.e. gastric banding, sleeve gastrectomy, Roux-en-Y bypass), chronic gastrointestinal disease including chronic diarrheal illness or inflammatory bowel disease Previous intolerance to fiber supplementation Allergy or intolerance to potato starch or maltodextrin Subject unwilling to comply with stool sample collection Not suitable for study participation due to other reasons at the discretion of the investigators