The Effect of Boron Supplementation on Kidney Stones in Patients With Nephrolithiasis: A Double‐Blind Randomized Controlled Trial

Kidney stones (nephrolithiasis) are a common and costly medical condition frequently linked with metabolic disorders. These disorders elevate the risk of serious complications and often necessitate invasive, expensive treatments, highlighting the need for alternative therapies. This study aimed to evaluate the effects of boron supplementation-in the form of boric acid and boron citrate-on kidney stone size and number in patients with nephrolithiasis. In this double-blind, randomized, placebo-controlled clinical trial, 60 eligible patients aged 20-65 years with nephrolithiasis were enrolled. Participants were randomly assigned to receive daily oral supplements for 8 weeks: boric acid (10 mg), boron citrate (10 mg), or placebo. The primary outcomes were kidney stone size and number; secondary outcomes included paraclinical parameters. Boron supplementation with either boric acid or boron citrate did not significantly reduce the number of kidney stones in fully adjusted models compared to the control group. The incidence rate ratios (IRR) were 1.09 (95% CI: 0.65-1.85; <i>p</i>-value = 0.740) for boric acid and 1.30 (95% CI: 0.79-2.13; <i>p</i>-value = 0.296) for boron citrate. Quade analysis also revealed no significant differences in kidney stone size among the groups. Regarding laboratory parameters, only urine phosphorus levels were significantly elevated in the boric acid group compared to placebo. No other clinically relevant effects were observed. Despite previous preliminary evidence, this study found no beneficial evidence for boron supplementation in patients with nephrolithiasis. <b>Trial Registration:</b> IRCT20210914052469N1 (www.irct.behdasht.gov.ir).