A groundbreaking study published last week in Mayo Clinic Proceedings has revealed that shift workers face a 15% higher risk of developing kidney stones, with the greatest risk observed among younger employees and those engaged in less physically demanding jobs.

The research underscores the urgent need to extend kidney stone prevention efforts to this often-overlooked group, the authors say. 

Shift work—defined as irregular work hours outside of the conventional 9-to-5 schedule, including night shifts—has long been associated with various health risks, including cardiovascular disease, metabolic syndrome, and mental health disorders. However, until now, the link between shift work and kidney stone disease had received little scientific scrutiny. 

The study, led by Dr Yin Yang, PhD, of the Department of Epidemiology at Sun Yat-sen University in Guangzhou, China, analysed data from more than 220,000 participants in the UK Biobank over a median follow-up period of nearly 14 years. Researchers examined different aspects of shift work—its type, frequency, and duration—and assessed kidney stone events during the study period.

A comprehensive review

“This is the first population-based cohort study to comprehensively evaluate how various shift work patterns contribute to kidney stone risk,” Dr Yang said. “We found that shift work is associated with a higher risk of kidney stone events; an association partially mediated by lifestyle factors such as smoking, sleep patterns, fluid intake, and body mass index (BMI).” 

Interestingly, the study found that participants with longer histories of shift work showed a slightly lower risk of kidney stones, a phenomenon the authors suggest could be due to a “healthy worker effect” or physiological adaptation over time—an area that warrants further investigation. 

Kidney stone disease is both common and preventable, with global prevalence estimates ranging from 1% to 13%. The condition can be silent or cause severe complications, including intense pain and hospitalisation. More importantly, kidney stones are linked to longer-term health problems such as chronic kidney disease and cardiovascular disease. 

In an editorial accompanying the study, Dr Felix Knauf, MD, from Mayo Clinic’s Division of Nephrology and Hypertension, highlighted the role of circadian rhythm disruption in kidney stone development. 

“A central effect of shift work is the disruption of circadian rhythms,” Dr Knauf explained.

“These internal biological clocks regulate nearly all physiological systems, including those governing water balance and solute homeostasis—processes crucial to preventing kidney stone formation.” 

The research suggests that initiatives targeting modifiable lifestyle habits—such as increasing daily water intake, improving sleep hygiene, encouraging physical activity, maintaining healthy body weight, and supporting smoking cessation—could reduce the kidney stone risk in shift workers. 

Dr Yang emphasised, “Supporting healthy lifestyle habits among shift workers could have a meaningful impact on their urological health. Workplace health promotion programs should integrate education about weight management, fluid intake, healthy sleep, reduced sedentary behaviour, and smoking cessation.” 

Given the global rise in non-traditional working hours, the findings highlight an urgent priority for both employers and public health officials: implementing strategies that safeguard the health of workers whose schedules deviate from the traditional workday.