Nitrogénretenció

Nitrogénretenció, often translated as nitrogen retention, refers to the physiological state where the amount of nitrogen absorbed from the diet is greater than the amount excreted by the body. Nitrogen is a crucial component of amino acids, which are the building blocks of proteins. Therefore, nitrogen balance is intimately linked to protein metabolism and overall body protein synthesis.

Positive nitrogen balance, indicating nitrogen retention, typically occurs during periods of growth, such as childhood and adolescence, during pregnancy, and when muscle mass is being built, such as during strength training or recovery from injury or illness. In these states, the body requires more protein to synthesize new tissues.

Conversely, negative nitrogen balance occurs when nitrogen excretion exceeds nitrogen intake. This can happen during periods of starvation, severe illness, trauma, or prolonged catabolic states, where the body is breaking down its own tissues for energy or to meet essential metabolic demands.

Measuring nitrogen balance involves quantifying the nitrogen consumed in food and the nitrogen lost through urine, feces, sweat, and other bodily secretions. While a direct measure of nitrogen balance is complex, it serves as a fundamental concept in understanding protein metabolism, nutritional status, and the body's response to various physiological and pathological conditions. It is a key indicator of whether the body is in an anabolic (building up) or catabolic (breaking down) state with respect to protein.