scholarly journals Effects of a 14-Day Hydration Intervention on Individuals with Habitually Low Fluid Intake

Author(s):  
Aaron R. Caldwell ◽  
Megan E. Rosa-Caldwell ◽  
Carson Keeter ◽  
Evan C. Johnson ◽  
François Péronnet ◽  
...  

<b><i>Background:</i></b> Debate continues over whether or not individuals with low total water intake (TWI) are in a chronic fluid deficit (i.e., low total body water) [<xref ref-type="bibr" rid="ref1">1</xref>]. When women with habitually low TWI (1.6 ± 0.5 L/day) increased their fluid intake (3.5 ± 0.1 L/day) for 4 days 24-h urine osmolality decreased, but there was no change in body weight, a proxy for total body water (TBW) [<xref ref-type="bibr" rid="ref2">2</xref>]. In a small (<i>n</i> = 5) study of adult men, there were no observable changes in TBW, as measured by bioelectrical impedance, after increasing TWI for 4 weeks [<xref ref-type="bibr" rid="ref3">3</xref>]. However, body weight increased and salivary osmolality decreased indicating that the study may have been underpowered to detect changes in TBW. Further, no studies to date have measured changes in blood volume (BV) when TWI is increased. <b><i>Objectives:</i></b> Therefore, the purpose of this study was to identify individuals with habitually low fluid intake and determine if increasing TWI, for 14 days, resulted in changes in TBW or BV. <b><i>Methods:</i></b> In order to identify individuals with low TWI, 889 healthy adults were screened. Participants with a self-reported TWI less than 1.8 L/day (men) or 1.2 L/day (women), and a 24-h urine osmolality greater than 800 mOsm were included in the intervention phase of the study. For the intervention phase, 15 participants were assigned to the experimental group and 8 participants were assigned to the control group. The intervention period lasted for 14 days and consisted of 2 visits to our laboratory: one before the intervention (baseline) and 14 days into the intervention (14-day follow-up). At these visits, BV was measured using a CO-rebreathe procedure and deuterium oxide (D<sub>2</sub>O) was administered to measure TBW. Urine samples were collected immediately prior, and 3–8 h after the D<sub>2</sub>O dose to allow for equilibration. Prior to each visit, participants collected 24-h urine to measure 24-h hydration status. After the baseline visit, the experimental group increased their TWI to 3.7 L for males and 2.7 L for females in order to meet the current Institute of Medicine recommendations for TWI. <b><i>Results:</i></b> Twenty-four-hour urine osmolality decreased (−438.7 ± 362.1 mOsm; <i>p</i> &#x3c; 0.001) and urine volume increased (1,526 ± 869 mL; <i>p</i> &#x3c; 0.001) in the experimental group from baseline, while there were no differences in osmolality (−74.7 ± 572 mOsm; <i>p</i> = 0.45), or urine volume (−32 ± 1,376 mL; <i>p</i> = 0.89) in the control group. However, there were no changes in BV (Fig. <xref ref-type="fig" rid="f01">1</xref>a) or changes in TBW (Fig. <xref ref-type="fig" rid="f01">1</xref>b) in either group. <b><i>Conclusions:</i></b> Increasing fluid intake in individuals with habitually low TWI increases 24-h urine volume and decreases urine osmolality but does not result in changes in TBW or BV. These findings are in agreement with previous work indicating that TWI interventions lasting 3 days [<xref ref-type="bibr" rid="ref2">2</xref>] to 4 weeks [<xref ref-type="bibr" rid="ref3">3</xref>] do not result in changes in TBW. Current evidence would suggest that the benefits of increasing TWI are not related changes in TBW.

PEDIATRICS ◽  
1962 ◽  
Vol 29 (6) ◽  
pp. 883-889
Author(s):  
Wesley M. Clapp ◽  
L. Joseph Butterfield ◽  
Donough O'Brien

Normal values for both total body water and extracellular water have been determined in 86 premature infants aged 1 to 90 days and weighing 940 to 2,435 gm, with use of the techniques of deuterium oxide and bromide dilution. Nine full-term infants aged 1 to 6 days and weighing 2,590 to 4,985 gm were similarly studied. Nine infants with the respiratory distress syndrome and eight infants of toxemic mothers studied in the first 24 hours of life showed no significant difference in their body water compartments in comparison to a control group of normal infants matched for age and weight. Seven infants of diabetic mothers studied in the first 24 hours of life showed a significant decrease in total body water, expressed as percentage of body weight, with a normal intracellular to extracellular water ratio. These data indirectly support other evidence that there is an increase in body fat in these infants at birth. See Table in the PDF file


1969 ◽  
Vol 72 (1) ◽  
pp. 31-40 ◽  
Author(s):  
W. R. McManus ◽  
R. K. Prichard ◽  
Carolyn Baker ◽  
M. V. Petruchenia

SUMMARYThe use of tritiated water to estimate total body-water content of animals experiencing recovery from under-nutrition was studied.The time for equilibration of tritiated water (TOH), given intraperitoneally, with total body water (TBW) was determined in rabbits and in rats. As judged by the specific activity of blood water, equilibration had occurred by 76–125 min in the rabbit and did not appear to be affected by the plane of nutrition. However, between slaughter groups the specific activity of water obtained from the liver 180 min after injection of TOH was significantly different from the specific activity of water simultaneously obtained from the blood plasma. It is concluded that the liver is not a suitable tissue to use for testing achievement of equilibration.As judged by the specific activity of blood water compared to that of water from the whole body macerate, equilibration in mature rats either in stable body condition or undergoing rapid compensatory growth occurred in less than 60 min.A trial comparing TOH-space (corrected by 3% body weight) and actual TBW (by desiccation) was conducted on thirty rabbits which experienced under-nutrition followed by compensatory growth.Prior to under-nutrition the agreement between actual and estimated TBW was satisfactory and within 2·3%. During compensatory growth the agreement was poor— the TOH values over-estimating actual TBW by about 12%.A trial with mature rats confirmed the findings with rabbits. For rats in stable body weight the mean estimated TOH-space for fourteen animals was within 1·2% of the actual TBW. For fourteen rats undergoing compensatory growth the mean estimated TOH-space (corrected by 3% body weight) overestimated actual TBW by 6·2%.


1988 ◽  
Vol 47 (3) ◽  
pp. 435-445 ◽  
Author(s):  
F. R. Dunshea ◽  
A. W. Bell ◽  
K. D. Chandler ◽  
T. E. Trigg

ABSTRACTA two-pool model of tritiated water kinetics was investigated as a means of partitioning total body water into empty body water and gut water in 17 lactating goats. Empty body water, gut water and total body water were of a similar magnitude to, and highly correlated with, a rapidly equilibrating tritiated water pool, a more slowly equilibrating pool and the sum of these two pools, respectively.Empty body fat was poorly correlated with both live weight and empty body weight (R2 = 0·42 and 0·51, respectively). However, there was a strong inverse relationship between the water and fat contents of the empty body. Consequently, empty body fat was accurately predicted by a multiple regression equation which included both empty body weight and empty body water as independent variables (R2 = 0·97). Substitution of these variables with estimates derived from tritiated water kinetics still resulted in a high correlation (R2 = 0·88). Tritiated water kinetics offered little improvement over live weight alone in the prediction of empty body protein, empty body ash or fat-free empty body.


2020 ◽  
Vol 35 (Supplement_3) ◽  
Author(s):  
Anna Matyjek ◽  
Aleksandra Rymarz ◽  
Stanisław Niemczyk

Abstract Background and Aims One of the major symptoms of severe nephrotic syndrome is fluid retention. Fluid overload can induce cardiovascular damage. NT-proBNP (N-terminal pro-brain natriuretic peptide) and hsTnT (high sensitivity troponin T) are well known markers of this disorder. The aim of the study was to evaluate the association between volumes of body water compartments and markers of cardiovascular damage in patients with severe nephrotic syndrome (SNS) defined as nephrotic range proteinuria and hypalbuminaemia ≤ 2.5 g/dl. Method 40 patients with SNS and eGFR &gt;30 ml/min/1.73m2 formed the study group (SNSG) and 40 healthy volunteers without SNS matched according to age, sex, height, body mass and kidney function formed the control group (CG). In all participants serum creatinine, serum albumin concentration, daily proteinuria, hsTnT and NT-proBNP were measured. Body water compartments such as extracellular water (ECW), intracellular water (ICW), total body water (TBW), overhydration (OH) were assessed using Body Composition Monitor, Fresenius Medical Care. For statistical analysis Spearman’s correlation coefficients, chi2 or Mann-Whitney U tests were used (Statistica v 13.1). Results SNSG included 28 males (70%) and 12 females. Median age was 55 years (IQR 30-65), the mean daily proteinuria was 10.5 ±5.0 g. The characteristics of the study parameters in two groups are described in the table. Significantly higher hsTnT (18 vs 6 ng/l, p=0.0001) and NT-proBNP (294.8 vs 47.1 pg/ml, p=0.0003) levels were observed in the severe nephrotic syndrome group in comparison (SNSG) to CG. In SNSG extracellular water was significantly higher (20.9 ±5,2 vs 17.4 ±3.3 L, p=0.001) and intracellular water (ICW) was significantly lower (18.9 ±5.2 vs 21.4 ±4.8 L, p=0.034) in comparison to CG. Interestingly total body water (TBW) did not differ between the groups (39.8 ±8.6 vs 38.8 ±7.7 L, p=0.603). Also overhydration which is a derivative of ECW, was higher in SNSG (OH: 4.2 vs 0.3 L, p&lt;0.0001) than in CG. Significant, positive correlation was observed between OH and NT-proBNP (R=0.56, p&lt;0.0001) as well as hsTnT (R=0.60, p&lt;0.0001). We did not observed significant correlation between ECW and NT-proBNP or hsTnT. Conclusion In the severe nephrotic syndrome group fluid retention was associated with the increase in ECW and the decrease in ICW whereas TBW was the same in both groups. Such constellation can indicate for intracellular underhydration which was not describe so far. Overhydration, which is a derivative of ECW, positively correlated with markers of cardiovascular damage and can be important for patients with resistant SNS and can influence their prognosis.


PEDIATRICS ◽  
1951 ◽  
Vol 7 (3) ◽  
pp. 321-327 ◽  
Author(s):  
BENT J. FRIIS-HANSEN ◽  
MALCOLM HOLIDAY ◽  
THOMAS STAPLETON ◽  
WILLIAM M. WALLACE

Total body water was determined in 24 normal infants and children by deuterium oxide dilution and by the antipyrine method. A micro-modification of the antipyrine method is described. Agreement between the two methods for determining total body water was good. Total body water was found to be highest in premature and newborn babies, the values ranging from 70 to 83% of body weight. During the first 6 months of life there was a gradual decrease of body water as per cent body weight. From 6 months to 11 years of age, the values varied between 53 and 63% with no correlation to age or sex.


1974 ◽  
Vol 82 (1) ◽  
pp. 105-112 ◽  
Author(s):  
B. S. W. Smith ◽  
A. R. Sykes

SUMMARYEight mature female sheep were offered a ration which maintained body weight constant during a 20-week period. During the final 10 weeks a comparison was made in each animal of the pattern of equilibration and urinary losses of tritiated water during 8 h after dosing by four different routes. These were intravenous, intraperitoneal, intraruminal and a combination of the intraperitoneal and intraruminal routes. Tritiated water spaces were calculated from (a) the 8-h plasma specific activity and (b) by extrapolation to zero time of the plasma specific activities during the 7 days after injection. At the end of the experiment the fat and water contents of the bodies of the sheep were determined directly.Complete equilibration of tritiated water between plasma and rumen water was not achieved in all animals 8 h after intravenous or intraperitoneal injection but was when the rumen was primed by the combination of intraperitoneal and intraruminal dosing. After intraruminal dosing equilibration was not achieved in any animal within 8 h of dosing.Urinary losses of marker were lower after intraruminal dosing but otherwise averaged 4–5 % of the dose/1 urine. This was equivalent to 0·3–6·7% of the dose for individual sheep.Errors resulting from incomplete equilibration and urinary loss of marker did not influence the efficiency of prediction of total body water from tritiated water space. The multiple correlation coefficient relating body fat with empty body weight and its water content was very high (r = 0·99). Errors introduced into this relationship by the inclusion of gut water in the prediction equations were apparently of a similar magnitude to those resulting from the errors in the estimation of tritiated water space.The extrapolation method for the determination of tritiated water space was shown to have the same accuracy as equilibration techniques under these controlled dietary conditions.


1977 ◽  
Vol 232 (1) ◽  
pp. R60-R65 ◽  
Author(s):  
J. M. Culebras ◽  
G. F. Fitzpatrick ◽  
M. F. Brennan ◽  
C. M. Boyden ◽  
F. D. Moore

Total body water (TBW) determination by tritium space could be factitiously elevated by exchangeable H+ contained within water-soluble chemical configurations. Should this nonaqueous (molecular) exchangeable H+ turn out to be a large fraction of total exchangeable H+, TBW measurement by tritiated water (THO) dilution would display a systematic upward and non-random error. TBW was measured by THO dilution and subsequently by total body desiccation in 21 rats (weight 227+/-83 g, mean+/-SD). TBW was 71.38+/-2.4% by THO dilution and 70.20+/-1.5% by body desiccation. Analysis of variance of TBW vs. body weight showed a highly significant correlation both with desiccation (P less than 0.0005, r=-0.78) and dilution (P less than 0.03, r= -0.50). Convariance analysis of both methods showed no difference in slope (P greater than 0.9). There was a difference in variance (P less than 0.001) and means (P less than 0.03). Tritium space is 1.2% of body weight larger than TBW measured by desiccation. TBW measured by THO dilution gives a 1.71% overestimation of TBW as measured by desiccation. TBW measurement by THO dilution is accurate within less than 2% error. These findings have particular significance in the light of our theoretical model of the total nonaqueous exchangeable H+ in fat, protein, and carbodhydrate in the living vertebrate.


1956 ◽  
Vol 34 (5) ◽  
pp. 959-966 ◽  
Author(s):  
C. Deb ◽  
J. S. Hart

Body fluid volumes and hematological values have been compared in rats exposed to 6 °C. for various periods of time and in rats at 30 °C. for comparable periods. Absolute blood and plasma volumes (T1824 space) decreased with time of exposure to 30 °C, while extracellular fluid volume (sodium space), total body water, and body weight increased. Rats transferred from the warm to the cold environment had larger plasma and blood volumes than those of rats at 30 °C. after the first week of exposure. After five weeks, blood volume was 22% greater on an absolute basis and 30% greater relative to total body water than that of the larger rats at 30 °C. There were no differences in extracellular fluid volumes between warm and cold exposed rats at comparable intervals. Total water and intracellular water tended to be greater in rats at 30 °C. on an absolute basis but they were much greater per unit body weight in rats at 6 °C. No differences were observed in red blood cell counts, in hemoglobin concentration, or in plasma specific gravity between warm and cold exposed rats, but there was an increased hematocrit, increased corpuscular volume, and decreased corpuscular hemoglobin content in rats kept at 6 °C. Hemoglobin, red cells, and plasma specific gravity increased with time in both groups.


2015 ◽  
Vol 16 (1) ◽  
Author(s):  
Joanna Kantyka ◽  
Damian Herman ◽  
Robert Roczniok ◽  
Lidia Kuba

AbstractPurpose. The aim of the present investigations was to determine the effects of aqua aerobics on body weight and composition, lipid profile, and selected blood count parameters in middle-aged sedentary females. Methods. Twenty-one women were randomly assigned to an experimental group (age 56.20 ± 2.57 years, height 162.80 ± 4.76 cm, weight 74.03 ± 3.84 kg) that participated in aqua aerobics classes three times a week for three months and a control group (mean age 56.44 ± 3.28 years, height 165.00 ± 3.91 cm, weight 70.01 ± 11.36 kg) not involved in any kind of targeted exercise. The aqua aerobics classes were tailored to suit the age and abilities of the participants, with workout intensity controlled and maintained at approximately 128-137 bpm. Results. Significant differences between the experimental and control groups were found for body weight, total body water, fat-free mass, and skeletal muscle mass. A significant increase in post-intervention hemoglobin and erythrocyte counts was observed in the experimental group. Conclusions. Future studies should determine the intensity of physical activity with the most beneficial effect on blood variables in middle-aged and older individuals.


Sign in / Sign up

Export Citation Format

Share Document