(OR01-03-26) Greater Plant Protein Intake and Diversity, but Not Animal Protein, Are Associated With Lower Malnutrition Risk Among Individuals With Oropharyngeal Cancer

Objectives: Oral intake is often compromised among individuals diagnosed with cancer, with 20–70% experiencing clinical malnutrition defined by significant weight and muscle loss. Adequate protein intake is central to preserving lean mass; however, whether protein source or diversity influences malnutrition risk across the cancer trajectory remains unclear. We examined the relationships between protein intake (quantity and diversity), overall, and by food source, with malnutrition risk among individuals diagnosed with oropharyngeal cancer (OPC).

Methods: This cross-sectional analysis included individuals with a first primary OPC diagnosis recruited from two large cancer centers. Diet was assessed using two interviewer-administered 24-hour recalls. Protein intake by food source (animal and plant) and protein diversity (count of distinct protein-containing foods) were averaged across recalls. Malnutrition risk was assessed using the Malnutrition Screening Tool (≥2 vs < 2). Multivariable logistic regression evaluated associations adjusting for age, sex, race/ethnicity, site, survivorship stage, smoking, and energy intake.

Results: Among 125 individuals diagnosed with OPC (n=52 at diagnosis; n=73 ≥ 18 months post-treatment), nearly 98% had poor diet quality (HEI-2020 < 70) and 4% met protein intake recommendations. Mean (± SD) total protein intake was 80 ±23 g/day, derived primarily from animal (59 ±24) rather than plant sources (21 ±8). In multivariable-adjusted models, greater quantity and diversity of plant protein were associated with lower malnutrition risk (OR[CI] per 10g/day: 0.36 [0.16-0.80] and OR[CI] per 0.5-unit: 0.22 [0.07-0.72]). No significant associations were observed for total or animal protein intake or diversity.

Conclusions: Within a dietary pattern characterized by suboptimal diet quality and predominantly animal-source protein intake, greater intake and diversity of plant-based protein were associated with lower malnutrition risk following OPC diagnosis. In this context, increasing the amount and variety of minimally processed plant protein foods may offer greater benefit than increasing total or animal protein alone. These findings underscore the potential relevance of protein source and diversity in nutritional risk across stages of cancer survivorship.

Funding Sources: Department of Defense