21st Century Daily Amino Acid, 120 Tablets – Essential Amino Acid Complex for Muscle Recovery, Energy & Overall Wellness 21st Century Daily Amino Acid, 120 Tablets – Essential Amino Acid Complex for Muscle Recovery, Energy & Overall Wellness 21st Century Daily Amino Acid is a comprehensive amino acid supplement formulated to provide a balanced blend of essential and non-essential amino acids. Amino acids are the building blocks of protein and play a vital role in muscle growth, recovery, energy production, and overall health. This formula is ideal for athletes, fitness enthusiasts, and individuals looking to support daily protein metabolism and muscle maintenance.