Yeast beta-glucan reprograms bone marrow in obese mice to restore anti-tumor immunity after weight loss

Researchers fed obese mice a high-fat diet with or without Wellmune yeast beta-glucan, then challenged them with three cancer lines. Supplemented animals showed enhanced trained immunity markers in bone marrow progenitors and improved tumor control; the effect held even after the mice lost weight, addressing a known clinical gap where obesity-induced immune defects linger. Sample size was modest per group and relied on syngeneic mouse models, limiting direct human translation. The dietary route succeeded where prior trained-immunity work needed injections, suggesting a low-barrier intervention. Context from human cohort studies links chronic low-grade inflammation in obesity to higher cancer incidence and poorer checkpoint-inhibitor responses; beta-glucan may intersect with those pathways by modulating myeloid progenitors. This raises the possibility of adjunct dietary strategies in immunotherapy, though effect sizes in lean versus obese hosts remain uncompared. Next steps require phase-I safety and pharmacodynamic trials in people with obesity or prior cancer, using Wellmune at doses already GRAS-approved, with endpoints focused on circulating NK and monocyte function within 8-12 weeks.