Why Muscle Loss Accelerates After 40 (And What You Can Do About It) Muscle loss after 40 is more common than most people realize. Research shows that adults can lose significant muscle mass over time if no preventive action is taken. This natural process, often associated with aging, can affect strength, metabolism, and overall vitality. Understanding why it happens is the first step toward preventing it. What Causes Muscle Loss After 40? As we age, several physiological changes occur: Reduced protein synthesis efficiency Hormonal changes Lower physical activity levels Reduced amino acid utilization Your body becomes less efficient at converting dietary protein into usable muscle tissue. This is sometimes referred to as “anabolic resistance.” The Role of Essential Amino Acids Essential amino acids are the building blocks your body cannot produce on its own. Without the right balance of these eight key amino acids, your body cannot effectively build new muscl...