Department of Medicine, University of Chicago, Chicago, Illinois.
Section of Nephrology, Department of Medicine, Università degli Studi di Verona, Verona, Italy.
Kidney360. 2024 Aug 1;5(8):1167-1177. doi: 10.34067/KID.0000000000000508. Epub 2024 Jul 16.
Higher dietary intakes of fructose and sucrose are associated with lower 24-hour urine calcium. Higher dietary intakes of fructose and sucrose are associated with other modest changes in 24-hour urine composition.
Consumption of sugar, including fructose and sucrose, is associated with higher risk of kidney stones. The association is believed to be because of an acute rise in urine calcium after sugar intake. However, the association between chronic sugar intake and urine composition is not known.
We conducted a cross-sectional analysis of dietary intake from a food frequency questionnaire and 24-hour urine collections from 6457 kidney stone- and non–stone-former participants from the Nurses' Health Study I (1,297), Nurses' Health Study II (4,053), and Health Professionals Follow-up Study (1,107). We used multivariate adjusted linear regression to examine the association between long-term intake of free fructose, total fructose, and sucrose and 24-hour urine composition.
Higher free and total fructose and sucrose intakes were each associated with lower 24-hour urine calcium. Comparing the highest versus lowest quintiles, mean urine calcium was 23 (31–15) mg/d lower for free fructose (-trend <0.001), 26 (34–18) mg/d for total fructose (-trend <0.001), and 8 (17–1) mg/d for sucrose (-trend 0.03). Higher total fructose intake was associated with slightly higher calcium phosphate supersaturation (-trend 0.002), and higher sucrose intake was associated with higher calcium oxalate (-trend 0.03) and calcium phosphate (-trend <0.001) supersaturations. Differences in 24-hour urine calcium were similar between kidney stone- and non–stone-former participants.
In contrast to the acute rise in urine calcium previously seen in short-term studies, higher long-term intake of free and total fructose and sucrose was associated with lower 24-hour urine calcium excretion in those with and without a history of kidney stones. Other modest differences in urine composition were noted for each sugar. Future studies should test potential mechanisms for the observed lower 24-hour urine calcium with chronic sugar intake.
果糖和蔗糖的较高膳食摄入量与 24 小时尿钙较低有关。果糖和蔗糖的较高膳食摄入量与 24 小时尿液成分的其他适度变化有关。
糖的消耗，包括果糖和蔗糖，与肾结石风险增加有关。这种关联被认为是由于糖摄入后尿液钙的急性升高。然而，慢性糖摄入与尿液成分之间的关系尚不清楚。
我们对来自护士健康研究 I（1,297 人）、护士健康研究 II（4,053 人）和健康专业人员随访研究（1,107 人）的食物频率问卷和 24 小时尿液收集进行了横断面分析。我们使用多变量调整线性回归来研究长期摄入游离果糖、总果糖和蔗糖与 24 小时尿液成分之间的关系。
游离和总果糖以及蔗糖的摄入量较高与 24 小时尿钙较低有关。比较最高和最低五分位数，游离果糖最高与最低五分位数相比，平均尿钙低 23（31-15）mg/d（-趋势<0.001），总果糖低 26（34-18）mg/d（-趋势<0.001），蔗糖低 8（17-1）mg/d（-趋势 0.03）。总果糖摄入量较高与钙磷盐过饱和度略有升高（-趋势 0.002）相关，而蔗糖摄入量较高与草酸钙（-趋势 0.03）和钙磷盐（-趋势<0.001）过饱和度升高有关。肾结石和非肾结石患者之间的 24 小时尿钙差异相似。
与短期研究中观察到的尿液钙急性升高相反，较高的游离和总果糖和蔗糖长期摄入量与肾结石和非肾结石患者的 24 小时尿钙排泄量较低有关。每种糖的尿液成分也有其他适度的差异。未来的研究应该测试慢性糖摄入与观察到的较低 24 小时尿钙之间的潜在机制。
