The Importance of Dietary Protein at Breakfast in ChildhoodLeonidas Karagounis
Proteins (derived from the Greek word πρώτειος [proteios] meaning “first one” or “most important one”) are the major functional and structural components of all the cells of the body and participate in virtually all biological processes occurring in the body. Protein provides amino acids to the body that are used to build and maintain bones, muscles, and skin, and to produce molecules with important physiological roles, such as enzymes, hormones, neurotransmitters, and antibodies. To this end, dietary protein intake is imperative in child nutrition because, unlike adults, children are in a state of ongoing growth with nutrition and exercise being the most potent stimulators of physical growth and development [1–3]. To support normal growth and this activity-induced augmentation of lean mass, adequate dietary protein ingestion is important for providing the requisite substrates to support the remodeling and growth of these lean tissues, including muscles . Skeletal muscle is the most abundant tissue in the body comprising 40–50% of body mass in humans and making up a large component of the overall lean tissue component. Beyond locomotion, skeletal muscle plays a key role in central metabolism and is responsible for about 60–70% of total glucose uptake and, therefore, directly impacting metabolic health . Skeletal muscle as well as the whole body protein pool is highly metabolic and undergoes rapid diurnal turnover, a process that is intricately regulated by the balance between the rates of protein synthesis and degradation. The increase in whole body protein balance is an important adaptive response to both contractile activity (i.e., exercise) and nutrient availability (i.e., protein ingestion) .
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