Influence of diet on acid-base balance

It is well established that diet and certain food components have a clear i mpact on acid-base balance. For adults, the following Factors are involved: 1) the chemical composition of foods (i.e., their content of protein, chlo ride, phosphorus, sodium, potassium, calcium, and magnesium), 2) the differ ent intestinal absorption rates of the relevant nutrients, 3) the metabolic generation of sulfate from sulfur-containing amino acids, 4) the grade of dissociation of phosphorus at the physiologic pH of 7.4, and 5) the ionic v alence of calcium and magnesium. All these factors allow us to estimate the potential renal acid load (PRAL) of any given food or diet. The PRAL (calc ulated for a 24-hour period), together with a relatively constant daily amo unt of urinary excreted organic acids (in healthy subjects proportional to body surface area or body weight), yields the daily net acid excretion. Thi s article provides an overview of the current concepts of diet influences o n acid-base balance and also focuses on the underlying physiologic and bioc hemical basis as well as on relevant clinical implications.