On 2017 Sep 02, Lise Bankir commented:

After we published the paper above " Relationship between Sodium Intake and Water Intake: The False and the True", we rediscovered a publication that we should have mentioned in this paper because it is one more study showing no change in urine volume (= water excretion) in normal subjects in response to marked changes in sodium intake (leading to corresponding changes in sodium excretion). The reference of this paper is : Hormonal responses to gradual changes in dietary sodium intake in humans. Sagnella GA, Markandu ND, Buckley MG, Miller MA, Singer DR, MacGregor GA. Am J Physiol. 1989 Jun;256(6 Pt 2):R1171-5. PMID: 2525347

Table 1 shows urine volumes in six normal subjects submitted to increasing sodium intakes. After 4 days on a very low sodium intake (12 mmol/24h), sodium intake was increased gradually by 50 mmol/day on successive days. For sodium intakes of 10, 50, 100, 150, 200, 300, 350, 350 mmol/day, urine volumes were 1.43, 1.40, 1.23, 1.38, 1.47, 1.96, 1.69, 1.53 L/24h, respectively. No comment is made in the paper about this relatively stable urine volume.

This study, like several others cited in our paper, confirms that urine volume, and thus probably fluid intake, do not increase with increasing sodium intake without other changes, when studied in healthy young subjects.

This observation in 1989 is at variance with the results of an experimental study reported by the same group in 2001, in hypertensive patients (off their usual treatment for 3 months). Effect of salt intake on renal excretion of water in humans. He FJ, Markandu ND, Sagnella GA, MacGregor GA. Hypertension. 2001 Sep;38(3):317-20. PMID: 11566897

After a few days on a 350 mmol/day salt intake, these hypertensive patients were switched to a low salt intake of 10-20 mmol/day. Urine volume fell significantly from 2.2 ± 0.09 to 1.3 ± 0.05 L/day. The difference between the two studies can possibly be explained by the fact that the 1989 study was conducted in healthy young subjects (age range 19-21 y) whereas the 2001 study concerned hypertensive patients (mean age 48 y, range 19-70).

On 2017 Sep 02, Lise Bankir commented:

After we published the paper above " Relationship between Sodium Intake and Water Intake: The False and the True", we rediscovered a publication that we should have mentioned in this paper because it is one more study showing no change in urine volume (= water excretion) in normal subjects in response to marked changes in sodium intake (leading to corresponding changes in sodium excretion). The reference of this paper is : Hormonal responses to gradual changes in dietary sodium intake in humans. Sagnella GA, Markandu ND, Buckley MG, Miller MA, Singer DR, MacGregor GA. Am J Physiol. 1989 Jun;256(6 Pt 2):R1171-5. PMID: 2525347

Table 1 shows urine volumes in six normal subjects submitted to increasing sodium intakes. After 4 days on a very low sodium intake (12 mmol/24h), sodium intake was increased gradually by 50 mmol/day on successive days. For sodium intakes of 10, 50, 100, 150, 200, 300, 350, 350 mmol/day, urine volumes were 1.43, 1.40, 1.23, 1.38, 1.47, 1.96, 1.69, 1.53 L/24h, respectively. No comment is made in the paper about this relatively stable urine volume.

This study, like several others cited in our paper, confirms that urine volume, and thus probably fluid intake, do not increase with increasing sodium intake without other changes, when studied in healthy young subjects.

This observation in 1989 is at variance with the results of an experimental study reported by the same group in 2001, in hypertensive patients (off their usual treatment for 3 months). Effect of salt intake on renal excretion of water in humans. He FJ, Markandu ND, Sagnella GA, MacGregor GA. Hypertension. 2001 Sep;38(3):317-20. PMID: 11566897

After a few days on a 350 mmol/day salt intake, these hypertensive patients were switched to a low salt intake of 10-20 mmol/day. Urine volume fell significantly from 2.2 ± 0.09 to 1.3 ± 0.05 L/day. The difference between the two studies can possibly be explained by the fact that the 1989 study was conducted in healthy young subjects (age range 19-21 y) whereas the 2001 study concerned hypertensive patients (mean age 48 y, range 19-70).