Significance of adjusting salt intake by body weight in the evaluation of dietary salt and blood pressure

- We investigated the significance of body weight-adjusted salt intake.
- Salt intake of 7629 participants was assessed using a spot urine test.
- Total salt intake increased with increasing body weight.
- Body weight-adjusted salt intake related to blood pressure and target organ damage.
- Adjustment for body weight might provide clinically important information.

The close association between dietary salt and hypertension is well established. However, previous studies generally assessed salt intake without adjustment for body weight. Herein, we investigated the significance of body weight-adjusted salt intake in the general population. The present cross-sectional study included 7629 participants from our yearly physical checkup program, and their salt intake was assessed using a spot urine test to estimate 24-hour urinary salt excretion. Total salt intake increased with increasing body weight. Body weight-adjusted salt intake was greater in participants with hypertension than in those without hypertension. Systolic blood pressure, estimated glomerular filtration rate, and urinary albumin were independently correlated with body weight-adjusted salt intake after adjustment for possible cardiovascular risk factors. Excessive body weight-adjusted salt intake could be related to an increase in blood pressure and hypertensive organ damage. Adjustment for body weight might therefore provide clinically important information when assessing individual salt intake.