Table 2.

Changea in indices of total water intake and body water flux, regulation, distribution, and volume in Week 6 relative to baseline for each study participant

	Change from Week 1 to Week 6 for each participant
Participant ID	1	2	3	4	5
Total water intake
L/dayb	+1.0	+1.7	+0.8	+1.5	+0.7
mL/kcal intake	+0.6	+1.3	+0.6	+0.3	+0.4
mL/kg body weight	+16	+24	+11	+21	+11
% Change vs Week 2	+38	+51	+17	+46	+32
Body water flux
Half‐life of water in the body, %c	−31	−38	−15	−11	−21
Half‐life of water in the body, days	−4.7	−6.7	−1.7	−1.6	−2.5
Body water regulation
Thirst, mmd	−12	−4	+10	+15	−21
Serum osmolality, mmol/kge	−5	−2	+1	+3	−5
Urine ADH, pmol/Lf	+5.1	−11.8	−9.6	−16.5	+0.2
Plasma aldosterone, pg/mLe	+31	+15	+4	+73	+37
Plasma vitamin D 1,25, pg/mLe	+23	+10	+14	+27	+39
Serum Na, mmol/Le	−2	0	+2	+1	+3
Serum K, mmol/Le	−0.3	+0.3	0	+0.1	−0.1
RBC K:Nae	−0.7	−0.6	−1.8	−1.5	−1.7
Fasting RMR, kcal/dayg	−5	+532	−341	−275	−595
Urine Na, mmol/Lh	+46	−74	−81	−65	−129
Urine K, mmol/Lh	−76	−10	−11	−10	−72
Urine osmolality, mmol/kgh	−342	−270	−244	−304	−817
Urine norepinephrine, ug/g crtf	+29	+30	+5	−28	−41
Systolic blood pressure, mmHge	+2	+15	0	+5	−18
Diastolic blood pressure, mmHge	−3	+1	+3	−3	−8
Serum BUN: creatininee	+2	−7	−4	−1	−5
Body water distribution
BIA height‐squared/reactance, cm2/Ωg		−0.4	+1.6	−0.3	+0.6
Manual hematocrit, %e	+1	−2	−1	0	−3
Automated hematocrit, %	−3	−2	−2	+2	−3
Body water volume
Saliva osmolality, mmol/kgd	+10	−5	−44	−19	−36
BIA height squared/resistance, cm2/Ωg		−1	+1	+2	0
Body weight, kgi	+1.9	+0.6	+1.3	+1.9	+0.4
Body weight, % change	+3.0	+0.9	+2.0	+2.7	+0.6

^aData are presented as the net change from Week 1 to Week 6 for each participant, n = 5, except for bioelectric impedance measures, which were missing for one participant due to instrument malfunction.

^bThe weekly mean intake was estimated from 7 24 h records.

^cThe half‐life of water in the body was estimated by deuterium elimination rate in Periods 1, 2, and 3.

^dThirst and overnight, water restricted, fasting saliva osmolality was assessed on arrival at the clinic.

^eBlood pressure was measured and fasting blood collected 90 min after a 750 mL water bolus.

^fUrine ADH and norepinephrine were determined on urine collected after the first morning void until 11 pm on the day before the clinic visit.

^gFasting, recumbent RMR and bioimpedance reactance were determined 60 min after the 750 mL water bolus.

^hUrine sodium, potassium, and osmolality were determined on first morning specimen collected at home before the clinic visit.

ⁱFasting body weight was measured when participants arrived at the clinic.