Effect of salt intake on renal excretion of water in humans

Citation
Fj. He et al., Effect of salt intake on renal excretion of water in humans, HYPERTENSIO, 38(3), 2001, pp. 317-320
Citations number
16
Categorie Soggetti
Cardiovascular & Respiratory Systems","Cardiovascular & Hematology Research
Journal title
HYPERTENSION
ISSN journal
0194911X → ACNP
Volume
38
Issue
3
Year of publication
2001
Pages
317 - 320
Database
ISI
SICI code
0194-911X(200109)38:3<317:EOSIOR>2.0.ZU;2-9
Abstract
Two studies were performed to determine the quantitative relationship betwe en salt intake and urinary volume (U-v) in humans. In study 1, 104 untreate d hypertensives were studied on the fifth day of a high- and a low-salt die t. The 24-hour U-v was 2.2 L (urinary sodium [U-Na] 277 mmol) on the high-s alt diet and decreased to 1.3 L (P<0.001) (U-Na 20.8 mmol) on the low-salt diet. The reduction in 24-hour U-v was significantly related to the decreas e in 24-hour U-Na (P<0.001) and predicts that a 100-mmol/d reduction in sal t intake would decrease 24-hour U-v by 367 mL. In study 2, 634 untreated hy pertensives were studied on their usual diet. There was a significant relat ionship between 24-hour U-v and U-Na (P<0.001). This predicts that a 100-mm ol/d reduction in salt intake would decrease 24-hour U-v by 454 mL. The Int ernational Study of Salt and Blood Pressure (INTERSALT) of 1731 hypertensiv es and 8343 normotensives on their usual diet showed that 24-hour U-v was s ignificantly related to U-Na (P<0.001) and predicted that a 100-mmol/d redu ction in salt intake would decrease 24-hour U-v by 379 and 399 mL in hypert ensives and normotensives, respectively. These findings document the import ant effect that salt intake has on U-v. The recommended reduction in salt i ntake in the general population is from 10 to 5 g/d. This would reduce flui d intake in the population by approximate to 350 mL/d per person. This woul d have a large impact on the sales of soft drinks, mineral water, and beer.