What is the main function of proteins in the body?

Proteins serve a vital role in the body, primarily known for their function in building and maintaining cells and tissues. They are made up of amino acids, which are essential for synthesizing new proteins that support growth, repair, and overall cellular function. This includes the formation of muscle tissue, structural components of cells, enzymes, hormones, and immune system molecules.

In addition to their structural role, proteins are integral to various biological processes, as they influence everything from muscle contraction to cellular communication. Unlike carbohydrates, which are primarily energy sources, proteins are not typically used for immediate energy but rather serve more complex functions that sustain body framework and processes. This distinction underscores why the option focusing on building and maintaining cells and tissues accurately represents the main function of proteins in the body.