What nutrient is primarily responsible for growth and repair of tissues?

Protein is the nutrient primarily responsible for growth and repair of tissues due to its structure and function in the body. Proteins are made up of amino acids, which are the building blocks that our cells use to create new tissues, including muscles, skin, and organs. During periods of growth, such as childhood and adolescence, and during recovery from injuries, the body requires an increased intake of protein to support the synthesis of new tissues and repair damaged ones.

Additionally, proteins play critical roles in various biological processes, such as enzyme function, hormone production, and immune response. This multifaceted role emphasizes why adequate protein intake is crucial for overall health and recovery. Other nutrients, while important, do not serve the specific functions associated with tissue growth and repair in the same direct manner that proteins do.