The role of dietary protein in the treatment and prevention of metabolic diseases

Abstract

Protein is an indispensable macronutrient whose structural and regulatory roles are modified throughout the human lifespan, from fetal programming to the mitigation of sarcopenia in old age. Modern nutritional science is moving beyond a purely “protein-centric” model, viewing protein intake through the lens of source quality (animal vs. plant-based), amino acid profile, and impact on the gut ecosystem. dietary protein plays a fundamental role in the treatment and prevention of socially significant metabolic diseases, including type 2 diabetes mellitus, obesity, and sarcopenia. among proteins of various origins, milk protein holds a special place due to its unique combination of anabolic, satietogenic, and bioregulatory properties, and serves as a precursor of bioactive peptides with antihypertensive, antidiabetic, and anti-inflammatory effects. This review analyzes the differentiated protein requirements across key age cohorts, the molecular mechanisms of protein effects on the gut microbiota, the role of milk-derived bioactive peptides in correcting metabolic syndrome, the evidence base for the efficacy of milk components in sarcopenia, and formulates practical recommendations for achieving active longevity.