Nutrition as the foundation for successful aging: a focus on dietary protein and omega-3 polyunsaturated fatty acids.

This article focuses on the role of skeletal muscle and nutrition, specifically dietary protein and omega-3 polyunsaturated fatty acids (n-3 PUFAs), in promoting successful aging (SA), defined here as low cardiometabolic risk, preserved physical function, and positive wellbeing. It highlights that sarcopenia, the age-related loss of skeletal muscle mass and function, increases risks of chronic disease, disability, and mortality, while adequate intake of high-quality protein and n-3 PUFAs (notably eicosapentaenoic acid [EPA] and docosahexaenoic acid [DHA]) may help maintain muscle mass and function in older adults. The review discusses current dietary recommendations, evidence from observational and interventional studies, and potential mechanisms involving the mechanistic target of rapamycin complex 1 (mTORC1) pathway and neuroregulation that underlie the additive benefits of protein and n-3 PUFAs. It concludes that intakes of protein above the Recommended Daily Allowance (RDA) and n-3 PUFAs above Dietary Guidelines for Americans (DGA) recommendations are likely necessary to support skeletal muscle health and SA, though further research is needed to clarify their combined effects on muscle, cardiometabolic health, physical function, and wellbeing.