Record ID: MS-N084 · Family: Nutrition and dietary patterns / investigational prevention · Clinical question: Can a high-fiber plant-based diet alter progression from MGUS or smoldering myeloma?

Evidence label: Early single-arm feasibility evidence with metabolic, quality-of-life and biological changes; no controlled evidence that it prevents progression to myeloma.

Evidence at a glance

• Benefit: The 12-week meal program was feasible and improved BMI, adherence, quality-of-life and selected metabolic, microbiome and immune measures.
• Certainty: Very low for cancer prevention; there was no control group and only 23 participants.
• Risk: Unintended weight loss, inadequate protein or micronutrients and gastrointestinal symptoms if poorly planned.
• Cancer control: Not established. Biomarkers, microbiome changes and animal experiments cannot demonstrate prevention of multiple myeloma.

What was studied

NUTRIVENTION was a single-center, single-arm pilot enrolling 23 people with MGUS or smoldering multiple myeloma and BMI at least 25. It provided high-fiber, minimally processed plant-based meals for 12 weeks and coaching for 24 weeks, without prescribed calorie restriction.

The primary feasibility target combined at least 70% of calories from minimally processed plant foods with a mean BMI reduction of at least 5% at week 12. Twenty participants completed week 12 and 18 had week-52 data.

What the results show

The study met its feasibility target: all completing participants achieved the dietary-adherence threshold and mean BMI was at least 5% lower at week 12. Quality-of-life and selected insulin-resistance, microbiome and immune measures improved.

Because everyone received the intervention, natural fluctuation, regression to the mean, attention, weight loss and other concurrent changes cannot be separated. Changes in M-spike trajectory in a subset and accompanying mouse experiments are exploratory, not evidence that the diet prevents human progression.

Important limits

• No randomized or concurrent control group.
• Small sample, single center and attrition from 23 enrolled to 20 at week 12 and 18 at week 52.
• Multiple secondary biomarkers increase the chance of selective or false-positive signals.
• MGUS and smoldering myeloma have heterogeneous baseline progression risk.
• The provided-meal and coaching model may not generalize to self-directed diets.

Safety and practical context

People with a myeloma precursor condition still need standard laboratory and clinical surveillance. Diet should not delay marrow evaluation or treatment when progression criteria are met. A dietitian can protect protein, vitamin B12, iron, calcium, vitamin D and total energy intake.

Questions for the care team

• What is my individual baseline risk of progression and surveillance schedule?
• Is weight loss appropriate for me?
• How will protein, B12, iron and other nutrients be monitored?
• Are we discussing quality of life and metabolic health—or an unproven claim to prevent myeloma?

Sources checked

• NUTRIVENTION clinical and preclinical report, Cancer Discovery 2026 (PMID 41342739)
• NUTRIVENTION registry record (NCT04920084)

Funding and conflicts: The publication lists institutional, philanthropic and federal support, including NHLBI grant K08HL143189; the full conflict-of-interest statement should be consulted because investigators and a commercial meal provider participated.

Last literature search: October 20, 2026 · Record appraisal: October 20, 2026

Educational information only. This record is not a prescription and does not replace advice from the oncology team, registered dietitian or oncology pharmacist.