Debunking the plant protein paradox

The increasing adoption of plant-based diets (PBDs) has raised questions regarding their adequacy in supporting muscular strength and performance, particularly given concerns around the amino acid profile and bioavailability of plant proteins. This review synthesises current meta-analytical and clinical trial evidence to address the "plant protein paradox," which posits that plant proteins are inferior for maintaining muscle mass and strength. Recent high-quality data reveal no significant differences in muscular strength or athletic performance outcomes between plant-based and omnivorous diets when total protein intake and quality are optimised. Mechanistic studies demonstrate comparable muscle protein synthesis rates across protein sources, with soy and certain mixed plant proteins showing anabolic potential equivalent to animal proteins. Clinical recommendations emphasise attention to protein quantity, quality, leucine content, and micronutrient sufficiency to maximise muscle health on PBDs. Specific populations—including older adults and athletes—can safely adopt plant-based nutrition without compromising strength or functional performance. This evidence supports a shift beyond traditional, protein hierarchy models, positioning plant-based diets as a viable strategy for musculoskeletal health alongside their cardiovascular and environmental benefits.