The association between dietary calcium intake and hyperuricemia among Chinese adults: results from the China Health and Nutrition Survey in 2009

Previous studies have shown that the intake of some specific dietary nutrients is associated with the risk of hyperuricemia (HUA). However, the relationship between dietary calcium intake and HUA remains unknown. Participants aged 18–94 years were identified from the China Health and Nutrition Survey (CHNS) in 2009. Three consecutive 24-h dietary recalls were used to assess estimated dietary intake. Multivariable logistic regression and linear regression were performed to evaluate the relationships between dietary calcium intake and HUA and serum uric acid, respectively, after adjustment for potential confounders. A restricted cubic spline (RCS) was used to visualize the nonlinear or linear relationship of this relationship. A total of 7606 participants were enrolled. The prevalence of HUA was 15.67% (20.21% for males, 11.66% for females), and the median estimated calcium intake was 352.87 mg/day. Compared with the lowest quintile (Q1) of dietary calcium intake, the multivariable-adjusted odds ratio ( OR ) and 95% confidence interval ( CI ) for HUA in Q4 and Q5 were 1.31 (1.02, 1.68) and 1.55 (1.18, 2.04), respectively ( P for trend = 0.002). Relative to those of participants with Q1 calcium intake, the regression coefficients ( β ) and 95% ( CI ) of participants with Q3, Q4, and Q5 for serum uric acid were 7.57 (1.58, 13.56), 13.92 (7.73, 20.11), and 14.76 (7.73, 21.79), respectively, and there was a clear positive linear dose‒response relationship ( P for nonlinearity = 0.057). There is a positive association between dietary calcium intake and HUA in individuals who habitually consume low levels of calcium, primarily from vegetables.