Dietary Zinc Intake and Kidney Stone Formation: Evaluation of NHANES III

Abstract

Aims: We aimed to determine whether there is an association between dietary zinc intake (DZI) and prevalent kidney stone disease defined as self-report of any previous episode of kidney stone. Methods: We examined The Third National Health and Nutrition Examination Survey (NHANES III), a large US population-based cross-sectional study, and used logistic regression analyses to determine the independent association between DZI and prevalent kidney stone disease. Results: A total of 15,444 men and women over 18 years of age were eligible for analysis. Among them, 710 participants reported a history of kidney stones. Stone formers tended to have higher DZI than non-stone formers among NHANES III participants, though this difference did not reach statistical significance (p = 0.1). Multivariate adjusted logistic regression analysis revealed that higher DZI (log transformed) was associated with a significantly increased risk of kidney stone disease (odds ratio, OR = 1.41, 95% confidence interval, CI: 1.10–1.81, p = 0.01). After categorizing zinc intake into three groups, those with highest DZI (>15 mg/day) were also associated with a significantly increased risk of kidney stone disease, compared to those with lower DZI (<7 mg/day; OR = 1.70, 95% CI: 1.13–2.57, p = 0.01). Conclusions: Our study suggests that higher DZI is associated with increased risk of kidney stone disease. Future prospective studies are needed to clarify the causal relationship between zinc intake and kidney stone formation.

Urinary Stone Disease: Advancing Knowledge, Patient Care, and Population Health

“…Strontium, cadmium, and zinc are trace elements and have been associated with USD in laboratory and epidemiologic studies (39,40). Additionally, calcium oxalate stones have been found to contain zinc and strontium (39).…”

“…Vitamin D supplementation, conversely, has not been associated with stones (52), perhaps because its conversion to 1,25-dihydroxyvitamin D is limited by activity of 1-a-hydroxylase. An association between high dietary zinc intake and an increased odds of USD has been observed (40).…”

The elementome of calcium-based urinary stones and its role in urolithiasis

“…Two studies using data from the Third National Health and Nutrition Examination Survey (NHANES III) and the European Prospective Investigation into Cancer and Nutrition (EPIC) reported an association between high dietary zinc intake and increased risk of urinary stones. 78,79 However, attempts to assess zinc status in individual patients have resulted in conflicting information. Data from a report published in 1963 and one publication from 2007 showed that calcium-based stone formers had lower urinary zinc levels compared with controls, consistent with an inhibitory effect of zinc on calcium-based stone formation.…”

Dietary Zinc and Incident Calcium Kidney Stones in Adolescence

“…9 We increased planned enrollment to 60 participants because prior studies of zinc and kidney stone disease did not include dietary phytate in the analyses. Because phytate binds zinc in the gut and also may directly inhibit stone formation, we anticipated that more patients would be needed to detect an association between zinc and kidney stones after adjusting for phytate.…”

“…In a study using the National Health and Nutrition Examination Survey (NHANES), dietary zinc intake was higher among older adults with nephrolithiasis, but lower among younger adults with nephrolithiasis. 9 Earlier studies examining urinary zinc levels in adults with and without nephrolithiasis also reported disparate results. 10, 11 These prior studies were cross-sectional, included only adults, and were likely confounded by unmeasured dietary intakes such as phytate, which binds zinc in the gut and decreases its bioavailability.…”