Proteins are the major components of every living cell. Dietary proteins are found in foods such as meat, poultry, egg, yogurts and nuts. Proteins in a balanced diet are essential in facilitating a wide array of regulatory functions such as hormone control, immune system regulation and acting as a biological catalyst.
Proteins are utilized in the synthesis of bones, teeth, hair, skin and other organ tissues. The supply of proteins in our diet maintains the continuous growth of cells. Hence, protein-rich foods are called body-building foods.
According to the Harvard School of Public Health, "Protein malnutrition leads to the condition known as kwashiorkor. Lack of protein can cause growth failure, loss of muscle mass, decreased immunity, weakening of the heart and respiratory system, and death."
Proteins form enzymes that serve as catalysts of biochemical reactions occurring in our body. These enzymes are necessary to ensure that processes occur at normal rates. The common biochemical reactions are respiration, digestion, energy production and excretion. For instance, the liver detoxifies our body by utilizing enzymes; a lack of these proteins may lead to impaired liver function due to the accumulation of toxic substances.
Proteins are utilized by muscle cells during body movements. Actin and myosin are among the proteins that facilitate muscle contractions. These proteins enable voluntary movements such as rotation of the hands and feet. Furthermore, proteins facilitate vital involuntary movements such as the repetitive beating of cardiac muscles.
Proteins play an important role in hormone regulation. Hormones are substances released in the bloodstream as a result of certain chemical reactions. For instance, proteins in the form of growth hormones signal the transformation and development of cells during puberty.
Proteins are needed in maintaining the body's resistance to infectious diseases. Immunoglobulins are proteins that release antibodies to kill the bacteria, virus or toxins entering the bloodstream. For instance, dust and dirt entering our eyes trigger the formation of tears, which contain antibodies.