Dietary protein considerations in a sustainable and ageing world: a narrative review with a focus on greenhouse gas emissions and skeletal muscle remodelling and maintenance

• Published in: BMC musculoskeletal disorders 2024-12, Vol.25 (1), p.1030-14, Article 1030
• Main Authors: Morgan, Paul T, Carson, Brian P, Witard, Oliver C
• Format: Article
• Language: English
• Subjects: Age; Ageing; Aging; Aging - metabolism; Aging - physiology; Amino acids; Animals; Bioavailability; Carbon footprint; Climate change; Diet; Dietary intake; Dietary Proteins - administration & dosage; Dietary Proteins - metabolism; Emissions; Emissions (Pollution); Environmental aspects; Environmental impact; Environmental sustainability; Food chains; Food intake; Food plants; Food quality; Food sources; Greenhouse Effect - prevention & control; Greenhouse gases; Greenhouse Gases - toxicity; Health aspects; High protein diet; Humans; Malnutrition; Muscle; Muscle diseases; Muscle, Skeletal - metabolism; Muscles; Musculoskeletal system; Nutrition research; Older people; Plant-based foods; Population; Prevention; Protein; Protein quality; Protein sources; Proteins; Proteins in human nutrition; Sarcopenia; Sarcopenia - diet therapy; Sarcopenia - etiology; Sarcopenia - metabolism; Sarcopenia - prevention & control; Skeletal muscle; Sustainability; Sustainable development
• ISSN: 1471-2474; 1471-2474
• DOI: 10.1186/s12891-024-07945-6

The rise in interest of plant-based protein foods has been meteoric, often leading to calls to adopt exclusively plant-based diets to reduce the intake of animal-based foods. In addition to impacts on human health, moving to an exclusively plant-based (or indeed animal-based) diet may have detrimental implications in terms of environmental sustainability. The impact of a rapid growth in global population on the sustainability of food systems poses clear consequences for the environment and thus warrants careful consideration at a national and, in some cases, global level. The requirement for high-quality dietary protein in an ageing population to offset chronic disease, such as sarcopenia, is an additional consideration. A reductionist approach to this sustainability issue is to advise a global population switch to plant-based diets. From a dietary protein perspective, the sustainability of different non-animal-derived protein sources is a complex issue. In this review, first we describe the role of dietary protein in combatting the age-related decline in skeletal muscle mass. Next, we explore the efficacy and sustainability of protein sources beyond animal-based proteins to facilitate skeletal muscle remodelling in older age. Taking a holistic approach, we discuss protein sources in terms of the muscle anabolic potential, environmental considerations with a predominant focus on greenhouse gas emissions across the food chain, the relevance of global malnutrition, and nation- and local-specific nutritional needs for dietary protein choices and food systems. Finally, we discuss implications for environmental sustainability and explore the potential of a trade-off between diet quality and environmental sustainability with food choices and recommendations.