One Dietary Pattern Stands Out in Study Examining Lung Cancer Risk in 95,612 Adults - Video

Could everyday dietary choices influence lung cancer risk through changes in gut bacteria? A new study suggests that diets associated with sulfur-metabolizing gut microbes may be linked to a higher risk of developing lung cancer and dying from the disease.

Published in Nutrition Journal, the study investigated the association between a sulfur microbial diet (SMD) score and lung cancer incidence and mortality among 95,612 adults participating in the U.S. Prostate, Lung, Colorectal, and Ovarian (PLCO) Cancer Screening Trial.

Lung cancer remains the leading cause of cancer-related deaths worldwide. Although smoking is its primary risk factor, researchers are increasingly exploring how dietary patterns and gut microbial activity may influence cancer development.

The study included participants with an average age of 65.5 years, approximately 52% of whom were women. Researchers calculated SMD scores using dietary questionnaires covering 25 food groups. Higher scores generally reflected greater consumption of red and processed meats, French fries and high-fat dairy products, alongside lower intake of fruits, vegetables and whole grains.

During follow-up, researchers recorded 1,561 lung cancer cases and 2,109 lung cancer-related deaths, with mortality monitored over a longer period.

After adjusting for demographic, lifestyle and clinical factors, participants with the highest SMD scores had a 23% higher estimated hazard of developing lung cancer and a 19% higher hazard of dying from the disease compared with those with the lowest scores.

The association with lung cancer mortality was particularly pronounced among individuals with a smoking history exceeding 20 pack-years. Stronger associations were also observed for squamous cell and small cell lung cancers.

Researchers suggested that sulfur-metabolizing gut bacteria may influence inflammation and cellular health through compounds such as hydrogen sulfide.

Importantly, the associations weakened after accounting for overall dietary quality and competing causes of death, raising uncertainty about whether the sulfur microbial dietary pattern independently contributes to cancer risk.

REFERENCE: Luo, Y., Xiao, Y., Yang, J., et al. (2026). Association of sulfur microbial diet with lung cancer incidence and lung cancer-related mortality in 95,612 American adults: a prospective cohort study from the PLCO trial. Nutrition Journal. DOI:10.1186/s12937-026-01406-7