The association between dietary intakes and stone formation in patients with urinary stones in Shiraz.

Background: Kidney stone is a common and costly disease, but it may be improved by a healthy diet. The aim of this study was to evaluate the association between dietary intake and stone formation in patients with urinary stones in Shiraz. Methods: In this cross sectional study, 110 patients with kidney stone were selected from Faghihi hospital, Shiraz. Demographic information was collected, and anthropometric indices, disease-related variables, physical activity (using IPAQ), and dietary intake (using food frequency questionnaire, analyzed by Nut 4 software, to estimate micro and macro nutrients) were evaluated. Independent sample t test and one-way ANOVA were used to compare the quantitative variables between the 2 groups and multi groups, respectively. Chi square test was also used to compare qualitative variables. The correlation between variables was determined using Pearson test. Results: Out of 110 participants in this study, 37 (33.6%) were female, with the mean BMI of 27.0 ± 4.68 kg/m2, and 73 (66.4%) were male, with the mean BMI of 24.21±2.96 kg/m2. The mean intake of calcium-containing foods (p=0.02) and high-fructose beverages (p=0.03) was significantly greater in patients with calcium stones compared to those with uric acid stones. The mean intake of high-purine foods was significantly higher in patients with uric acid stones than in those with calcium stones (p=0.007). The mean intake of vitamin A (p=0.02), beta-carotene (p=0.03), and fructose (p=0.03) was significantly higher in patients with calcium stones than in those with uric acid stones, while caffeine intake was significantly higher in patients with uric acid than in those with calcium stones (p=0.01). There was a significant correlation between consumption of high-oxalic beverages (p=0.005, correlation coefficient = 0.26) and high-fructose (p=0.048, correlation coefficient = 0.18) with spontaneous stone expulsion. Conclusion: There was a significant relationship between consuming vitamin A, beta-carotene, and foods containing calcium, purine, fructose, and oxalate and formation of kidney stones. Therefore, adopting a healthy diet and increasing physical activity may be effective in the treatment of kidney stones.