Malnutrition occurs when your diet lacks any of the essential nutrients you need for good health. Protein deficiency, in particular, results from insufficient dietary protein or from consuming poor-quality proteins over an extended period of time. Symptoms of protein deficiency may strike any part of your body that requires protein, and your muscles, being protein rich, may become weak when your diet is low in high-quality protein. Seek the advice of your health care provider or a nutritionist if you suffer from muscle weakness or suspect a protein deficiency.
Protein Function
Protein is the most abundant nonwater substance in your body, and all the cells of your body contain some protein. Protein supports the components of your immune system, repairs and builds tissue, synthesizes blood cells and manufactures enzymes and hormones. Protein also serves a structural role in your body, as it is a primary component of your muscles. Protein deficiency may impact any of these protein-dependent functions, and muscle weakness may be one of the earliest deficiency symptoms when your diet lacks this vital nutrient.
Requirements
The amount of protein you need to consume each day to prevent a deficiency varies depending on your size, state of health and activity level. Most healthy adults require 0.8 g of protein for each kg of body weight. Thus, a person weighing 150 lb. needs to take in 68 g of protein daily for optimal health. The quality of your food protein also matters. Plant proteins do not contain all the essential amino acids -- those you must consume in your diet because your body cannot synthesize them -- and, unless you carefully combine different plant proteins to include all the amino acids you need, a protein deficiency may result. Animal proteins are nutritionally complete, but if you consume insufficient amounts, deficiency symptoms such as muscle weakness may occur even if your dietary protein is of high quality.
Deficiency
When your diet lacks one or more essential amino acids, whether from eating poor-quality protein or inadequate levels of high-quality protein, your body treats your muscle stores as an amino acid reserve of sorts. In other words, when your body needs to synthesize a protein -- for example, as part of an immune cell or a blood cell -- but your diet does not supply its requisite amino acids, it will degrade your muscle protein to retrieve the amino acids in short supply. This process, over time, results in depletion of your muscle tissue, and, as your muscle tissue decreases, your muscles grow progressively weaker.
Considerations
In addition to muscle weakness, other symptoms of protein deficiency include fatigue, increased susceptibility to infection, lethargy and changes in your hair or skin. Although protein deficiency is not common in the U.S., it may occur, especially if you depend on plant-based foods as your sole source of protein.
Member Comments