Dietary sodium and cardiovascular morbidity/mortality: a brief commentary on the ‘J-shape hypothesis’

Abstract

The last decade, a growing number of evidence support Jshape or inverse -instead of positive linear -associations between dietary sodium intake and cardiovascular morbidity/mortality. A careful evaluation of these studies leads to the following observations: less accurate methods for dietary sodium assessment are usually used; most studies included high-risk participants, enhancing the possibility of a 'reverse causality' phenomenon. However, these limitations do not explain all the findings. Few carefully designed randomized clinical trials comparing different levels of sodium intake that address the issue of the optimal and safe range exist; therefore, current guidelines recommend a higher cut-off instead of a safe range of intake. Given the demonstrated harmful effects of very low sodium diets leading to subclinical vascular damage in animal studies, the 'J-shape hypothesis' cannot yet be either neglected or verified. There is a great need of well-designed general population-based prospective randomized clinical trials to address the issue.

Association between dietary quality and accelerated aging: a cross-sectional study of two cohorts

“…Some studies suggest a “J-shaped” relationship between salt intake and the incidence of cardiovascular events. 31 However, the presence of a comparable relationship between salt intake and aging necessitates further evidence for validation.…”

“…Some studies suggest a "J-shaped" relationship between salt intake and the incidence of cardiovascular events. 31 However, the presence of a comparable relationship between salt intake and aging necessitates further evidence for validation. We conducted analyses in different subgroups to explore the relationship between dietary quality and accelerated aging, assessing potential variations among populations with distinct characteristics.…”

Excessive salt intake accelerates the progression of cerebral small vessel disease in older adults

“…Studies have shown that there is a J-shaped association of dietary salt intake with mortality and cardiovascular events [ 33 , 34 ]. In this study, we found that the new-incident CSVD was positively correlated with salt intake and the J-shape curve was less obvious.…”

Serum osmolality was non-linearly associated with the risk of all-cause and cardiovascular mortality in patients with diabetes

“… 5 An acute decrease in serum osmolality was also a risk factor for potentially severe postoperative neurologic complications following kidney transplantation. 6 It has been proven that the components of the formula, namely sodium, 7 blood urea nitrogen, 8 serum glucose, 9 and other parameters interacting with osmolality such as serum albumin 10 and renal function, 11 affect all-cause and cause-specific mortality in general population, while few studies have elucidated about the prognostic meaning of osmolality itself in all-cause and cause-specific mortality in diabetic population.…”