High-Fiber Plant-Based Diet Shows Promise in Preventing Multiple Myeloma Progression in At-Risk Patients

A small but promising clinical trial suggests that patients at high risk for multiple myeloma (search)Search disease may be able to delay or prevent cancer progression through dietary intervention. The study, presented at the American Society of Hematology (search)Search term annual meeting, found that a high-fiber, plant-based diet produced significant improvements in disease markers and metabolic health among patients with precancerous conditions.

Study Design and Participants

The pilot study, part of the NUTRIVENTION Trials conducted at Memorial Sloan Kettering Cancer CenterView company profile, enrolled 20 patients with monoclonal gammopathy of undetermined significance (search)Search disease (MGUS (search)Search disease) who were also overweight or obese. MGUS is a bone marrow abnormality that often serves as a precursor to multiple myeloma (search)Search disease, one of the most common forms of blood cancer (search)Search disease.

"With cancers being detected earlier and precancerous states identified more frequently, there is a growing opportunity to understand how modifiable risk factors-like diet and lifestyle-affect cancer progression," said Francesca Castro, clinical research dietitian at Memorial Sloan Kettering Cancer CenterView company profile.

Participants received 12 weeks of high-fiber, plant-based meals followed by 24 weeks of individualized nutritional counseling, with follow-up extending to 52 weeks. The intervention encouraged consumption of whole plant-based foods including fruits, vegetables, nuts, seeds, whole grains, and legumes, while avoiding refined grains, animal products, added sugar, and highly processed foods.

Significant Dietary Adherence and Weight Loss

The results demonstrated remarkable dietary adherence. Before the study began, only 20% of participants' total calories came from high-fiber plant-based foods. By the end of the 12-week intervention, this figure jumped to 91%. Participants were allowed to eat to satiety as long as they adhered to the prescribed foods.

Weight loss outcomes were substantial and sustained. Participants lost an average of 8% of their starting body weight after 12 weeks, with the median BMI dropping by 7%. This weight reduction was maintained at the one-year follow-up.

Disease Progression and Clinical Outcomes

The dietary intervention appeared to influence disease trajectory. Two patients whose MGUS (search)Search disease was already showing signs of progressing to cancer experienced "a significant improvement of their disease progression trajectory," according to the researchers. Notably, none of the participants had progressed to multiple myeloma (search)Search disease by one year after enrolling in the trial.

"This study showcases the power of nutrition -- specifically a high fiber, plant-based diet -- and unlocks a better understanding of how it can lead to improvements in the microbiome and metabolism to build a stronger immune system," said Dr. Urvi Shah, the study's lead author and myeloma specialist at Memorial Sloan Kettering Cancer CenterView company profile.

Metabolic and Immune System Improvements

Beyond weight loss and disease progression, participants showed comprehensive health improvements. The researchers observed significant enhancements in insulin resistance markers, lipid profiles, inflammation levels, and gut microbiome diversity and composition. These improvements were sustained throughout the 52-week follow-up period.

The study also documented improvements in overall quality of life and dietary quality scores. According to Shah, the comprehensive analysis of improved immune and metabolic response suggests that a high-fiber plant-based diet could also reduce risk for cardiovascular conditions, diabetes (search)Search disease, and other metabolic conditions.

Scientific Rationale and Future Research

The findings align with previous research suggesting that poor-quality, meat-rich diets increase multiple myeloma (search)Search disease risk, while obesity serves as an additional risk factor for MGUS (search)Search disease progression to cancer. Prior studies in mice had found that 44% of myeloma-prone mice fed a high-fiber diet did not progress to the disease, while mice eating normally all developed the cancer.

"Our study shows the power of nutrition in the preventative setting and showcases the potential to give patients a sense of agency in their diagnosis," said Shah. "With everything that patients cannot control during and before cancer treatment, studying diet provides an opportunity for patients to make a difference in their disease risk and the potential success of their treatment."

The research team is currently enrolling participants in larger follow-up NUTRIVENTION Trials involving 150 MGUS (search)Search disease patients. They also plan to investigate the effects of diet versus supplements on the gut microbiome and study the effects of high-fiber plant-based diets on other precursor blood conditions, such as clonal hematopoiesis, which increases risk for other blood cancers including leukemia (search)Search disease.

Clinical Implementation Recommendations

For patients interested in increasing fiber intake, Castro suggests setting realistic daily goals and focusing on one meal at a time. "Think about what foods you can add or swap to increase fiber intake," she said. "It can be very simple like adding a piece of fruit at the end of a meal or swapping out a refined grain for a whole grain."

The researchers note that most Americans fall short of the approximately 28 grams of fiber per day recommended by US Dietary Guidelines. The study's findings support how physicians can empower patients, especially those with precancerous conditions, with knowledge about reducing cancer risk through dietary changes.