Negri Armando L, Spivacow Francisco R, Del Valle Elisa E
Instituto de Investigaciones Metabólicas, Universidad del Salvador, Buenos Aires, Argentina.
Medicina (B Aires). 2013;73(3):267-71.
The composition of urine is influenced by diet and changes in dietary factors have been proposed to modify the risk of recurrent nephrolithiasis. Nutrients that have been implicated include calcium, oxalate, sodium, animal protein, magnesium and potassium. There is significant evidence showing that a high calcium diet is associated with a reduction of lithogenic risk. One of the possible mechanisms to explain this apparent paradox is that the higher intake of calcium in the intestine binds with dietary oxalate, reducing its absorption and urinary excretion. Oxalate from the diet seems to provide only a small contribution to excretion and dietary restriction is appropriate only in those with hyperoxaluria and hyperabsorption. Observational studies have shown a positive and independent association between sodium intake and the formation of new kidney stones. Consumption of animal protein creates an acid load that increases urinary excretion of calcium and uric acid and reduced citrate, all factors that could participate in the genesis of stones. Potassium-rich foods increase urinary citrate because of its alkali content. In prospective observational studies, diets rich in magnesium were associated with a lower risk of kidney stone formation in men. In conclusion, diet is a key element in the management of the patient with kidney stones but always subordinated to present metabolic risk factors.
尿液的成分受饮食影响，有人提出饮食因素的改变可降低复发性肾结石的风险。涉及的营养物质包括钙、草酸盐、钠、动物蛋白、镁和钾。有大量证据表明，高钙饮食与降低结石形成风险有关。解释这一明显矛盾现象的一种可能机制是，肠道中较高的钙摄入量与饮食中的草酸盐结合，减少其吸收和尿排泄。饮食中的草酸盐似乎对排泄的贡献很小，仅在高草酸尿症和高吸收者中进行饮食限制才合适。观察性研究表明，钠摄入量与新发肾结石的形成之间存在正相关且独立的关联。食用动物蛋白会产生酸负荷，增加钙和尿酸的尿排泄，并降低柠檬酸盐，所有这些因素都可能参与结石的形成。富含钾的食物因其碱性成分而增加尿柠檬酸盐。在前瞻性观察性研究中，富含镁的饮食与男性肾结石形成风险较低有关。总之，饮食是肾结石患者管理中的关键因素，但始终要服从于当前的代谢风险因素。
