PD32-02 THE IMPACT OF DIETARY ZINC ON URINARY 24-HOUR STONE RISK FACTORS (2014)

You have accessJournal of UrologyStone Disease: Evaluation II1 Apr 2014PD32-02 THE IMPACT OF DIETARY ZINC ON URINARY 24-HOUR STONE RISK FACTORS Thomas Chi, Eric Taylor, Daivd W. Killilea, Sarah Burke, Swapna V. Shenvi, Tai C. Holland, Barbara Sutherland, Mark K. Shigenaga, Janet C. King, and Marshall L. Stoller Thomas ChiThomas Chi More articles by this author , Eric TaylorEric Taylor More articles by this author , Daivd W. KillileaDaivd W. Killilea More articles by this author , Sarah BurkeSarah Burke More articles by this author , Swapna V. ShenviSwapna V. Shenvi More articles by this author , Tai C. HollandTai C. Holland More articles by this author , Barbara SutherlandBarbara Sutherland More articles by this author , Mark K. ShigenagaMark K. Shigenaga More articles by this author , Janet C. KingJanet C. King More articles by this author , and Marshall L. StollerMarshall L. Stoller More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2014.02.2273AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES Zinc has been implicated in the early development of urinary stones based upon known non-trace levels of zinc in kidney stones and Randall plaques. While zinc plays an integral role in many physiologic processes across multiple organ systems and it is likely tightly regulated under normal circumstances, it is unclear as to whether dietary zinc manipulation could have an impact on important urinary stone risk variables. This study was designed to assess the impact of dietary zinc depletion and repletion on 24-hour urinary stone risk factors in closely supervised male ambulatory human subjects. METHODS IRB approval was obtained for a 9-week zinc depletion/repletion study. Participants were ambulatory, drank water ad lib and only ate specially designed meals prepared and consumed at the study center three times per day. The study was designed with three distinct metabolic periods. During the first period, participants consumed a low zinc (6 mg/day) diet with phytate (1.5 g/day) for 2 weeks culminating in a first 24-hour urine collection. This was followed by 4 weeks of zinc repletion with a 10 mg Zn/day diet without phytate. On the last day of this period a second urine collection was performed. During the third recovery phase volunteers consumed a diet with 25 mg daily oral zinc supplements followed by a final urine collection. Blood, urine and fingernail samples were obtained during each study period. Means were calculated and an analysis of variance performed to compare 24-hour urine collection values between each the three study periods. RESULTS Nine of 11 male subjects completed all aspects of the study. Mean 24-hour urinary volumes ranged from 1.7 to 2.3 liters (p 0.21) between each study period. During the initial dietary zinc depletion period mean 24-hour urinary oxalate increased (37.4 to 58.8 mg/day, p <0.01), mean urinary pH increased (6.05 to 6.7, p <0.001) and urinary supersaturation of uric acid decreased (1.03 to 0.19, p < 0.02) compared to repletion values. The remaining 24-hour urinary measurements including sodium, calcium, uric acid, citrate, sulfur, urinary nitrogen, and chloride were not significantly different. CONCLUSIONS Urinary oxalate increased with dietary zinc depletion in this pilot human ambulatory study. Dietary zinc depletion also increased urinary pH and decreased supersaturation of uric acid and thus may be useful in a subset of stone patients. Further human studies are warranted to help understand the impact of dietary zinc on urinary stone risk parameters. © 2014FiguresReferencesRelatedDetails Volume 191Issue 4SApril 2014Page: e836 Advertisement Copyright & Permissions© 2014MetricsAuthor Information Thomas Chi More articles by this author Eric Taylor More articles by this author Daivd W. Killilea More articles by this author Sarah Burke More articles by this author Swapna V. Shenvi More articles by this author Tai C. Holland More articles by this author Barbara Sutherland More articles by this author Mark K. Shigenaga More articles by this author Janet C. King More articles by this author Marshall L. Stoller More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...