Adherence to a diet with higher protein quality significantly reduces the risk of lung cancer: results from a population-based prospective study.

BACKGROUND

The impact of protein quality on lung cancer risk in the U.S. population remains unclear. We conducted a large-scale prospective cohort study with 101,755 American adults enrolled in the Prostate, Lung, Colorectal, and Ovarian (PLCO) Cancer Screening Trial (1993-2001).

METHODS

The Healthy Plate Protein Quality Index (HPPQI) was used to assess dietary protein quality. Cox proportional hazards regression was applied to analyze the relationships between HPPQI and lung cancer incidence and mortality. Subgroup and sensitivity analyses were conducted.

RESULTS

Over a mean follow-up of 8.82 ± 1.95 years (897,809 person-years; median 9.40 years), 1,706 lung cancer cases (1,464 NSCLC and 242 SCLC) and 1,217 related deaths (1,005 NSCLC and 212 SCLC) were recorded. Higher HPPQI was significantly linked to lower lung cancer incidence (HR Q4 vs. Q1: 0.63; 95% CI: 0.55-0.73; P < 0.001 for trend) and mortality (HR Q4 vs. Q1: 0.62; 95% CI: 0.52-0.74; P < 0.001 for trend), consistent in both NSCLC and SCLC. Sensitivity analysis confirmed the study's robustness across various participant characteristics.

CONCLUSIONS

Adherence to a dietary pattern characterized by a higher HPPQI is associated with reduced lung cancer risk.