Having optimal levels of protein in your diet is important for a number of reasons. Protein is an essential macronutrient that helps build and maintain muscle mass, provides energy, and helps to keep your bones and organs healthy. 

Additionally, protein is important for the production of hormones and enzymes, as well as for the maintenance of healthy skin, nails, and hair. 

When it comes to muscle protein synthesis, consuming adequate amounts of protein is important for building and maintaining muscle mass. When you consume protein, your body breaks it down into amino acids, which are then used to build and repair muscle proteins. 

This process is known as muscle protein synthesis and is essential for muscle growth and recovery. On the other hand, having low levels of protein in your diet can lead to muscle protein breakdown. 

This is when your body breaks down muscle proteins for energy, as it is unable to get enough energy from other sources. This can lead to muscle loss and fatigue, as well as an increased risk of injury, especially in the elderly who are at more risk of muscle dystrophy.