A February 2025 Indiana University workshop asked over twenty international experts to pressure-test propositions about dietary protein: methodological limitations, ‘optimal’ intake for muscle synthesis, accretion, growth and repair, needs during weight loss, anabolic thresholds and potentially harmful high intakes. Experts rated evidence from strong support to sufficient to rule out. Most propositions required more research because studies lacked rigor, sample size, duration or relied on surrogate outcomes.
Key findings
- Some claims had support but many remained uncertain; rigor, size, duration and surrogate reliance were key gaps; optimal intake, thresholds and harms need population- and outcome-specific evidence.
Why this matters globally
The exercise challenges one-number-fits-all communication and frames research for older adults, athletes, weight loss, kidney or metabolic disease and general populations.
Thai researcher contribution
Wantanee Kriengsinyos of Mahidol University contributes Thai nutrition expertise to the international assessment.
Limitations to consider
Expert consensus is not a systematic review and depends on panel selection, framing and conflicts. Rating distributions are absent. Insufficient evidence is not evidence a claim is false, and the workshop does not produce direct clinical estimates or recommendations.