Our overarching hypothesis is that plant-based diets will induce beneficial modifications of the gut microbiota favoring short fatty acid (SCFA)-producing commensals and a more advantageous CD8/Th17 ratio in sMM patients, thus preventing evolution to MM. Goal of this national, prospective, multicenter study is to demonstrate that plant-based diets substantially modify the gut microbiome inducing increased production of SCFAs in patients affected by sMM. The study will involve up to 62 patients affected by sMM. 56 Enrolled and eligible patients will be encouraged to consume a balanced diet rich in fiber for the entire duration of the trial (i.e., 12 weeks). Patients will choose among a list of different diet plans or individual food according to the personal tastes and preference. Free outpatient medical visit will be performed at enrollment and at week 12, and nutritional counseling will be given at the time of enrollment, one month later and on demand. As in line with routine diagnosis and follow-up of for patients affected by sMM, the investigators will collect bone marrow aspirates and peripheral blood at the time of screening, for plasma, serum, and peripheral blood mononuclear cells (PBMCs), while stool samples will be collected immediately before diet initiation. The investigators will also collect stool samples 4 and 12 weeks after diet initiation, and peripheral blood at 12 weeks after study initiation (as per routine clinical follow-up of this patient population). Dietary measurements will be conducted along the entire duration of the nutritional regimen by questionnaires. Biological paired comparison will be conducted between data obtained from samples collected at time 0 and samples collected 4 and 12 weeks later.
Participant is willing and able to give informed consent for participation in the study.
Confirmed diagnosis of sMM according to IMWG criteria
Absence of features of symptomatic or active myeloma requiring treatment (myeloma-defining events).
Aged ≥18 and </= 75 years
Non-Caucasian subjects. Racial disparities in all stages of the disease characterize MM, and Blacks have an increased MGUS and MM risk and higher mortality rate than Whites.
Patients that already follow a whole food plant-based diet (≥ 40g/die;ovo-lacto-vegetarian or processed junk food vegan diets are not excluded). These patients likely should already have high SCFA levels in their gut.
Legume allergy.
Severe allergies such as anaphylactic shock to nuts (specifically cashews).
Single group
diet rich in fiber
Dietary supplementEnrolled and eligible patients will be encouraged to consume a balanced diet rich in fiber for the entire duration of the trial (i.e., 12 weeks). Patients will also be encouraged to prolong plant-based diets beyond week 12. Free outpatient medical visit will be performed at enrollment and at week 12, and nutritional counseling will be given at the time of enrollment, one month later and on demand. Dietary measurements will be conducted along the entire duration of the nutritional regimen by questionnaires. In particular, the patient will write for each day of the trial the number associated to the chosen diet plan or food.
To evaluate the effects of high-fiber diets on mean SCFA concentration in stool samples.
Concentration of at least one among the three main SCFAs (acetate, butyrate and propionate) in stool samples from participants. Stool samples will be collected at Baseline visit (day 0) and 4 and 12 weeks later. SCFAs will be measured by targeted nuclear magnetic resonance.
To evaluate adherence to the diet regimen.
Frequency of participants adhering to the high-fiber diet (≥ 40g/die) at week 4 and 12 weeks since the start.
To evaluate the effects of high-fiber diets on gut microbiome composition.
Composition of the gut microbiota. Stool samples will be collected at Baseline visit (day 0) and 4 and 12 weeks later. Composition of the gut microbiota will be obtained by 16S ribosomal RNA sequencing of paired stool samples.
Click on the lead sponsor to view all of their trials.
Ciceri Fabio
Lead sponsor
IRCCS San Raffaele
Sponsor institution
