The global market for protein supplements and protein-fortified foods has grown into a multibillion-dollar industry, yet the respiratory consequences of this dietary shift have received little attention in the pulmonary literature. This review connects three threads that are usually examined in isolation: the economics of protein fortification, the consumer behavior that drives demand for high-protein products, and the clinical evidence linking protein intake to lung function and immune defense. Market analyses value the sector at roughly USD 28 to 63 billion in 2024 and 2025, with annual growth near 8 to 10 percent and a steady migration of buyers from athletes to older adults seeking protection against age-related muscle loss. Against this commercial backdrop, controlled trials and meta-analyses, though mostly of low certainty, associate adequate protein intake with better-preserved respiratory and skeletal muscle, a lower burden of the sarcopenia that complicates chronic obstructive pulmonary disease, and stronger immune competence during respiratory infection. The same products, however, carry a measurable burden of heavy-metal contamination, and chronic exposure to cadmium and lead is independently associated with impaired lung function and emphysema. Protein nutrition therefore sits at an underexamined intersection of commerce, public health, and respiratory medicine, and pulmonologists have practical reasons to ask patients what they consume. Priorities for future work include respiratory-specific protein intake guidelines, pharmacoeconomic analyses in respiratory care, and longitudinal monitoring of contaminant exposure in regular supplement users.

Keywords: Protein Supplementation; Food Fortification; Chronic Obstructive Pulmonary Disease; Sarcopenia; Respiratory Immunity; Gut-Lung Axis; Heavy Metal Contamination; Cadmium

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