This article examines the crucial role of different alternative protein sources in improving global food systems to address twenty-first century challenges such as population growth, climate change, resource scarcity, and the environmental impact of conventional animal production. The aim was to assess how these alternative sources contribute to food security, reduce ecological footprints, and facilitate systemic transitions toward environmental sustainability. The study employs a systematic review approach, analyzing scientific literature and institutional reports published between 2010 and 2025 from major databases. It evaluates five main categories of alternative proteins—plant-based, fungal, microbial, entomological, and cultivated—from environmental, nutritional, technological, economic, and sociocultural perspectives. The findings indicate that alternative proteins have smaller land, water, and greenhouse gas footprints compared to conventional red meat, although their performance varies by category and depends on energy sources, scalability, and regulatory conditions. Plant-based proteins are currently the most scalable and socially accepted, while fungal and microbial proteins offer high efficiency and industrial adaptability. Insect-derived proteins demonstrate high feed conversion efficiency and potential for the circular economy but face cultural barriers. Cultured meat represents a disruptive innovation with long-term environmental potential; however, significant technological and economic challenges remain. The study concludes that protein diversification does not represent an isolated substitution but rather functions as a systemic transformation strategy that depends on alignment with the energy transition, regulatory coherence, investment in research and infrastructure, and the design of inclusive policies.
Pablo Montero-Prado (Tue,) studied this question.