Protein deficiency is a state of malnutrition in which insufficient amounts of protein is taken in for the body to utilize in order to produce energy. This condition is largely responsible for the high incidence of starvation and disease in many Third World countries, causing death to millions of people each year. Sadly, many children under the age of five make up the majority of victims. However, protein deficiency also occurs in developed countries, primarily due to poverty. Certain individuals may also become prone to protein deficiency, such as crash dieters and vegetarians who neglect to properly balance their diet.
Protein is necessary for the body to synthesize 13 amino acids and to break down polypeptide molecules into the nine essential amino acids that the body cannot manufacture on its own. Collectively, these acids constantly work to replenish tissue in the body, so they play an important role in the maintenance of healthy bones, muscles, and organs. The body also uses protein to produce hemoglobin in red blood cells, the vehicle by which oxygen is transported to muscles and organs. In addition, without sufficient protein, the lungs and immune system would cease to function properly.
The body interprets a state of protein deficiency as a signal to enter into starvation mode. As a result, the body attempts to compensate for the deficiency by pulling out stores of protein in the body for recycling. The first source the body will turn to make a protein withdrawal is the muscles, which leads to a condition known as muscle wasting. In fact, weakness resulting from a loss in muscle mass is one of the first symptoms of protein deficiency.
Other symptoms of protein deficiency include weight loss, diarrhea, and an accumulation of fluids (edema) in the legs and abdomen. Initial outward signs include hair loss, scaly skin, and lethargy due to a lack of energy. If the deficiency continues, organs will begin to malfunction. For instance, since protein utilization is involved in the transport of lipoproteins and cholesterol, a lack thereof will lead to steatosis hepatitis, or fatty liver disease. In addition, the body will be unable to maintain normal levels of leukocytes, leaving the body deficient in white blood cells and the immune system unable to fight infections.
Generally speaking, children require 0.5 grams of protein for every pound (0.5 kilograms) of body weight and adults a total of approximately 60 grams of protein per day. However, pregnant or nursing women may require more. Aside from meat, eggs, and dairy, particularly good sources of protein include whole grains, beans, nuts, sunflower seeds, brown rice, potatoes, spinach, and broccoli.