Imbalance of protein homeostasis, with excessive protein degradation compared with protein synthesis, leads to the development of muscle atrophy resulting in a decrease in muscle mass and consequent muscle weakness and disability. Potential triggers of muscle atrophy include inflammation, malnutrition, aging, cancer, and an unhealthy lifestyle such as sedentariness and high fat diet. Nutraceuticals with preventive and therapeutic effects against muscle atrophy have recently received increasing attention since they are potentially more suitable for long-term use. The implementation of nutraceutical intervention might aid in the development and design of precision medicine strategies to reduce the burden of muscle atrophy. In this review, we will summarize the current knowledge on the importance of nutraceuticals in the prevention of skeletal muscle mass loss and recovery of muscle function. We also highlight the cellular and molecular mechanisms of these nutraceuticals and their possible pharmacological use, which is of great importance for the prevention and treatment of muscle atrophy.

γ-Poly-glutamic acid (γ-PGA) is a naturally occurring homo-polyamide produced by various strains of Bacillus. As a biopolymer substance, γ-PGA possesses a few predominant features containing good water solubility, biocompatibility, degradability and non-toxicity. Based on this, γ-PGA can be used in pharmaceutical, such as drug carrier/deliverer, vaccine adjuvant, and coating material for microencapsulation, etc. Moreover, it has also been applied in a broad range of industrial fields including food, medicine, bioremediation, cosmetics, and agriculture. Especially, γ-PGA is an extremely promising food ingredient. In this mini-review, our aim is to review the function and application progress of γ-PGA in the food industry: e.g., improving taste and flavor, enhancing physical property, and promoting health.