A Study Comparing a Plant-Based Diet With Supplements and Placebo in People With Monoclonal Gammopathy of Undetermined Significance (MGUS) or Smoldering Multiple Myeloma (SMM)

Inclusion Criteria:

• Confirmed diagnosis of MGUS or SMM

• If non light chain MGUS/SMM then M spike must be either ≥ 0.2 g/dL or BM PC ≥10% (both not required)

• If light chain MGUS/SMM then involved must be ≥10 mg/dL or BM PC ≥10% (both notrequired)

• If IgA MGUS/SMM then an IgA level >350 mg/dL and an abnormal immunofixation isrequired (M spike criteria not required).

• If IgD MGUS/SMM then an IgD level >50 mg/dL and an abnormal immunofixation isrequired (M spike criteria not required).

• Age ≥18 years

• Willingness to comply with all study-related procedures

• ECOG performance status of 0-3

• Interested in learning to cook plant based recipes

Exclusion Criteria:

• Patients that already follow a whole foods plant based diet (ovo-lacto-vegetarian orprocessed junk food vegan diets are not excluded)

• Legume allergy

• Severe allergies such as anaphylactic shock to nuts (specifically cashews). Peanutsare not included in the meals.

• Concurrent participation in weight loss/dietary/exercise programs

• Mental impairment leading to inability to cooperate

• Enrollment onto any other therapeutic investigational study concurrently and up to 180 days prior to study start date

• Concurrent pregnancy

• Positive HBV, HCV or HIV PCR test will need to be treated first and onceundetectable viral load patients may enroll

• ≥ Grade 2 electrolyte abnormalities as defined by CTCAEv5.0 (need to be resolvedbefore enrolling on study)

• If in the opinion of the investigator there maybe any concerns regarding the abilityof the patient to complete the study safely or any contraindications

• Heavy drinker (defined as >2 drinks per day or >14 drinks per week)

• Current self-reported illicit drug use (eg heroin, cocaine not marijuana)