Human heart. Credit: copyright American Heart Association

Salt (sodium chloride) is well-known to increase blood pressure and to be a target of public health intervention. However, some controversy remains about the role of salt in cardiovascular disease in the general population, because few relevant trials have been conducted and observational studies have not been definitive.

In a recent study published in Clinical Nutrition, CUNY SPH Professor Mary Schooling and University of Hong Kong Assistant Professor Shiu Lun Au Yeung compared risk of stroke, heart failure and type 2 diabetes according to genetically predicted levels of sodium excretion. Genetically predicted exposures are unlikely to be affected by factors that could affect sodium and disease meaning that using this study design helps provide reliable evidence.

The researchers found, as expected, that higher sodium excretion was associated with higher risk of stroke and heart failure. Higher sodium excretion was also found to be associated with type 2 diabetes.

"This study provides additional evidence supporting public health advice to reduce salt intake to help prevent and additionally suggests the benefits may extend to protecting against type 2 diabetes," says Dr. Schooling.

More information: Shiu Lun Au Yeung et al. Impact of urinary sodium on cardiovascular disease and risk factors: A 2 sample Mendelian randomization study, Clinical Nutrition (2020). DOI: 10.1016/j.clnu.2020.09.018