Diet and Gut Microbiome May Explain Cancer's "Obesity Paradox"

A McGill University study published in Nature found that some obesity-associated diets improved mice's response to immune checkpoint inhibitors. The effect appears driven by diet-microbiome interaction rather than body weight itself.

• 12 diets tested in mice; some obesogenic diets improved immunotherapy response
• Benefit appeared after short diet periods, not from long-term weight gain
• Treatment response may depend on what gut bacteria are fed
• Study published in Nature on July 8, 2026