Deuterium Oxide Dilution Research Articles

Criterion Validity of Screening Tools and Field-Based Tests for Health-Related Physical Fitness in Inflammatory Bowel Disease.

Monitoring health-related physical fitness (HRPF) may benefit proactive Inflammatory Bowel Disease (IBD) management. However, knowledge regarding HRPF in patients with IBD is limited and gold standard tests are impractical for widespread use, necessitating simpler methods. This study evaluated the criterion validity of screening tools and field-based tests compared to gold standard tests for HRPF in patients with IBD. Adult patients with IBD completed screening tools, field-based tests, and gold standard tests for HRPF. Criterion validity was examined through (intraclass) correlation coefficients and Bland-Altman plots. Predictive capacity of the screening tools was examined with receiver operating curve analysis. Among 53 included patients, screening tools demonstrated poor-to-moderate validity compared to the cardiopulmonary exercise test (CPET) for cardiorespiratory fitness. Very strong correlations were found for four-site skinfold thickness and multi-frequency bioimpedance analysis (BIA) with deuterium oxide dilution for body fat percentage (ICC = 0.90, ICC = 0.93), and between the steep ramp test and CPET (r = 0.95) for cardiorespiratory fitness. The steep ramp test also correlated strongly with isokinetic quadriceps (r > 0.75) and hamstring (r > 0.74) strength. Hand-held dynamometry and the sit-to-stand test showed strong correlations with hamstring strength (r > 0.80, r > 0.76). Negligible correlations were found for field-based tests compared to isokinetic quadriceps and hamstring endurance. Four-site skinfold thickness and BIA showed good agreement with the gold standard for body fat measurement. The steep ramp test demonstrated strong correlations with the gold standard tests for cardiorespiratory fitness and quadriceps and hamstring strength, while hand-held dynamometry and the sit-to-stand test showed strong correlations with hamstring strength.

Establishment of the deuterium oxide dilution method as a new possibility for determining the transendothelial water permeability

Increase in transendothelial water permeability is an essential etiological factor in a variety of diseases like edema and shock. Despite the high clinical relevance, there has been no precise method to detect transendothelial water flow until now. The deuterium oxide (D2O) dilution method, already established for measuring transepithelial water transport, was used to precisely determine the transendothelial water permeability. It detected appropriate transendothelial water flow induced by different hydrostatic forces. This was shown in four different endothelial cell types. The general experimental setup was verified by gravimetry and absorbance spectroscopy. Determination of transendothelial electrical resistance (TEER) and immunocytochemical staining for proteins of the cell-cell contacts were performed to ensure that no damage to the endothelium occurred because of the measurements. Furthermore, endothelial barrier function was modulated. Measurement of transendothelial water flux was verified by measuring the TEER, the apparent permeability coefficient and the electrical capacity. The barrier-promoting substances cyclic adenosine monophosphate and iloprost reduced TEER and electrical capacity and increased permeability. This was accompanied by a reduced transendothelial water flux. In contrast, the barrier-damaging substances thrombin, histamine and bradykinin reduced TEER and electrical capacity, but increased permeability. Here, an increased water flow was shown. This newly established in vitro method for direct measurement of transendothelial water permeability was verified as a highly precise technique in various assays. The use of patient-specific endothelial cells enables individualized precision medicine in the context of basic edema research, for example regarding the development of barrier-protective pharmaceuticals.

Accuracy and precision of multiple body composition methods and associations with muscle strength in athletes of varying hydration: The Da Kine Study

BackgroundAthletes vary in hydration status due to ongoing training regimes, diet demands, and extreme exertion. With water being one of the largest body composition compartments, its variation can cause misinterpretation of body composition assessments meant to monitor strength and training progress. In this study, we asked what accessible body composition approach could best quantify body composition in athletes with a variety of hydration levels. MethodsThe Da Kine Study recruited collegiate and intramural athletes to undergo a variety of body composition assessments including air-displacement plethysmography (ADP), deuterium-oxide dilution (D2O), dual-energy X-ray absorptiometry (DXA), underwater-weighing (UWW), 3D-optical (3DO) imaging, and bioelectrical impedance (BIA). Each of these methods generated 2- or 3-compartment body composition estimates of fat mass (FM) and fat-free mass (FFM) and was compared to equivalent measures of the criterion 6-compartment model (6CM) that accounts for variance in hydration. Body composition by each method was used to predict abdominal and thigh strength, assessed by isokinetic/isometric dynamometry. ResultsIn total, 70 (35 female) athletes with a mean age of 21.8 ± 4.2 years were recruited. Percent hydration (Body Water6CM/FFM6CM) had substantial variation in both males (63- 73%) and females (58- 78%). ADP and DXA FM and FF M had moderate to substantial agreement with the 6C model (Lin’s Concordance Coefficient [CCC] = 0.90-0.95) whereas the other measures had lesser agreement (CCC < 0.90) with one exception of 3DO FFM in females (CCC = 0.91). All measures of FFM produced excellent precision with %CV < 1.0 %. However, FM measures in general had worse precision (% CV < 2.0%). Increasing quartiles (significant p<0.001 trend) of 6CM FFM resulted in increasing strength measures in males and females. Moreover, the stronger the agreement between the alternative methods to the 6CM, the more robust their correlation with strength, irrespective of hydration status. ConclusionThe criterion 6CM showed the best association to strength regardless of the hydration status of the athletes for both males and females. Simpler methods showed high precision for both FM and FFM and those with the strongest agreement to the 6CM had the highest strength associations. Summary BoxThis study compared various body composition analysis methods in 70 athletes with varying states of hydration to the criterion 6-compartment model and assessed their relationship to muscle strength. The results showed that accurate and precise estimates of body composition can be determined in athletes, and a more accurate body composition measurement produces better strength estimates. The best laboratory-based techniques were air displacement plethysmography and dual-energy x-ray absorptiometry, while the commercial methods had moderate-poor agreement. Prioritizing accurate body composition assessment ensures better strength estimates in athletes.

Measurement of body composition by deuterium oxide dilution technique and development of a predictive equation for body fat mass among severe neurologically impaired children.

Neurologically impaired (NI) children are at risk of malnutrition, which consequently impacts their health and quality of life. Accurate nutrition assessment is an important step in guiding appropriate nutrition support. Conventional anthropometric measurements among NI children have some limitations. Determining body composition requires more complex equipment, which is not routinely performed. This study was conducted to evaluate the association between anthropometric parameters and body composition assessed using the deuterium dilution technique (DDT) in NI children. A cross-sectional study enrolled severe NI children aged 1-20 years who received home enteral nutrition for at least 3 months. Weight, length, and 4-site skinfold thickness were measured. Body composition was determined using DDT following the International Atomic Energy Agency (IAEA) protocol. A total of 37 NI children (56.76% male, median age 7.2 years) were enrolled. The prevalence of underweight, stunting, and overweight were 22, 38, and 35%, respectively. Body composition analysis showed the mean (SD) of total body water (TBW) and fat mass (FM) were 10.52 (4.51) kg and 9.51 (6.04) kg, respectively. Multivariate GLM analysis showed that the factors associated with FM were age (β = 0.07 [0.05,0.08]; p < 0.001), body mass index (BMI) (β = 0.82 [0.52, 1.12]; p < 0.001), biceps skinfold thickness (BSF) (β = 0.49 [0.23,0.75]; p = 0.001), and subscapular skinfold thickness (SSF) (β = -0.24 [-0.46,0.03]; p = 0.030). A predictive equation for FM was constructed. A high prevalence of malnutrition was found among severe NI children despite enteral nutrition support. Our findings showed that age, BMI, BSF, and SSF were associated with FM. The predictive equation of FM was proposed and needed to be further validated and applied to clinical practice.

Relationship of body mass index to percent body fat determined by deuterium isotopic dilution and impedancemetry among Tunisian schoolchildren.

This study aims to evaluate the relation of body mass index (BMI) to fat mass among children by two techniques impedancemetry and deuterium oxide dilution (D2O). This study was carried out in 156 schoolchildren aged between 8 and 11 years. The children received interrogation specifying lifestyle and food habits. Body composition was determined using the impedancemetry and D2O technique. The results showed a difference between the percentage of obese and overweight children according to BMIZ classification (30.1%), bioelectrical impedance method (14.7%) and D2O technique (42.9%). Despite the difference between the last two classifications, we found a significant correlation between body fat percentages determined by impedancemetry and D2O technique (r = 0.695, p<0.01). Bioelectrical impedance analysis underestimated %BF by 78.02% in overall children, by 70.05% in boys and by 84.73% in girls compared to D2O technique. This study has demonstrated that the percentage of overweight and obesity varied according the methods used. Further development of body composition methods is needed in children for the real determination of the obesity prevalence and therefore a better monitoring of this public health problem.

Influence of four fiber-rich supplements on digestibility of energy and nutrients and utilization of energy and nitrogen in early and mid-gestating sows.

The digestibility of energy and nutrients in fiber-rich diets depends greatly on the fiber source but most data are from studies with growing pigs. The purpose of this study was to investigate the apparent total tract digestibility (ATTD) of nutrients in different fiber-rich diets and to quantify whole-body metabolism and utilization of energy and nitrogen (N) in gestating sows. Four fiber-rich diets based on sugar beet pulp (SBP), soy hulls (SH), palm kernel expellers (PKE), or a mixed fiber (MF) were formulated, with an average daily intake of total fiber (TF) of 471, 507, 651, and 437 g/d, respectively. A total of 48 multiparous sows were stratified by body weight at mating (day 0) and assigned to one of the four diets throughout gestation. Body weight and backfat were measured, and body pools of fat and protein were estimated using the deuterium oxide dilution technique at days 0, 30, and 60. On days 30 and 60, urine and fecal grab samples were obtained. On days 15 and 45, heart rate was measured to estimate total heat production. The ATTD of nutrients differed across treatments (P < 0.001), while in vivo organic matter digestibility deviated with up to ±3.3% units from in vitro enzyme digestibility of organic matter. The ATTD of energy was highly negatively correlated with intake of lignin (P < 0.001), while ATTD of N was highest (negatively) correlated (P < 0.001) with intake of insoluble non-starch polysaccharides (NSP). The ATTD of all nutrients except NSP was lowest in PKE-fed sows and highest, except for N, in sows fed the SBP diet. The ATTD of N was highest in the MF-fed sows and ATTD of NSP was lowest in the MF-fed sows. Sows lost most energy as heat (53% to 72% of gross energy intake), followed by energy in feces (15% to 17%), urine (3% to 4%), and methane (0.5% to 0.9%). Energy for maintenance accounted for the majority of the heat production and the total energy retention was lowest and highest in the SBP- and PKE-fed sows, with a retention of 3.3 and 13.3 MJ/d, respectively (P < 0.001). Sows lost most N through urine, the lowest and highest N loss (relative to intake) was observed in SH- and SBP-fed sows (50% to 63%, respectively), while 14% to 26% was retained as body protein. In conclusion, the fiber-rich diets were utilized efficiently by gestating sows with respect to energy with ATTD values above 82% in all four fiber-rich diets, whereas the high TF content in the diets compromised the N utilization in gestating sows.

Body Composition in Youths Aged 10‒17 Years by Deuterium Oxide Dilution, Air Displacement Plethysmography, and DXA: Validation of the Medical Body Composition Analyzer Bioimpedance Device by a 4-Compartment Model

BackgroundThe medical body composition analyzer (mBCA) incorporates advances in multifrequency technology and has been validated using a 4-compartment (4C) model in adults but not in youths aged <18 y. ObjectivesThis study aimed to formulate a 4C model based on 3 reference methods and develop and validate a body composition prediction equation for the mBCA in youths aged 10‒17 y. MethodsThe body density of 60 female and male youths was measured by air displacement plethysmography, total body water by deuterium oxide dilution, and BMC by DXA. Data from the equation group (n = 30) were used to formulate a 4C model. The all-possible-regressions method was used to select variables. The model was validated in a second cohort (n = 30) in a random split design. The accuracy, precision, and potential bias were evaluated by the Bland and Altman procedure. ResultsMean age, weight (W), height (H), waist circumference, and z-score of BMI were 13.6 ± 2.3 y, 54.5 ± 15.5 kg, 156 ± 11.9 cm, 75.5 ± 10.9 cm, and 0.70 ± 1.32 z, respectively. The prediction equation was as follows: FFM in kg (FFMkg) = ([0.2081] ∗ [W] + [0.8814] ∗ [H2cm/RΩ] + [0.2055 ∗ XcΩ])–15.343; R2 = 0.96; standardized root-mean-square error (SRMSE) = 2.18 kg. FFM did not differ between the 4C method (38.9 ± 12.0 kg) and the mBCA (38.4 ± 11.4 kg) (P > 0.05). The relationship between these 2 variables did not deviate from the identity line, was not significantly different from 0, and the slope was not significantly different from 1.0. In the precision prediction model of mBCA, the R2 value was 0.98 and SRMSE was 2.1. No significant bias was found when regressing differences between methods and their means (P = 0.08). ConclusionsThe equation for the mBCA was accurate, precise, had no significant bias, had substantial strength of agreement and could be used in this age group when subjects were preferentially within the constraints of a specified body size.

Effect of multiday endurance exercise on total body water and calculated body composition in racing sled dogs

Prolonged multiday exercise in dogs is often associated with a caloric deficit that can lead to changes in body composition but may also result in an increase in lean body mass due to a conditioning effect. To test the hypothesis that multiday exercise decreases fat mass but increases lean body mass, body composition was measured using deuterium oxide dilution in a team of racing Alaskan sled dogs competing in a multiday race. Twelve dogs completed 961 km in 6 days, resulting in a 3% decrease in body mass (P=0.003) and 16% decrease in body fat (P=0.005), and an increase in total body water as a fraction of body mass (P=0.01). Within the study population, there was considerable dog-to-dog variation, with 2 dogs gaining fat mass and 2 dogs losing over 40% of their pre-race fat mass during the measurement period. These results confirm that dogs participating in multiday exercise events are at risk for loss of body fat reserve, likely due to a net calorie deficit. However, individual dog responses to an exercise challenge can be highly variable, emphasizing the need for careful assessment of individual dogs.

Use of bioelectrical impedance analysis in centenarians: a systematic review

BackgroundCentenarians often represent one of the best examples of aging successfully. However, the role of body composition or hydration status assessed with bioelectrical impedance analysis (BIA) is poorly explored in this population. Therefore, the aim of this systematic review was to better understand the use and the role of BIA for evaluating body composition and hydration status in centenarians.MethodsWe conducted a systematic review of the literature up to the 1st of May, 2022 for published articles providing data on BIA to evaluate body composition parameters or hydration status in centenarians. Data were summarized descriptively because a meta-analysis was not possible due to the scarcity of available studies.ResultsAmong 2222 articles screened, four were eligible including 291 centenarians (mean age: 100.5 years) who were mainly women (88%). In one study, BIA overestimated fat-free mass and underestimated fat mass when compared to deuterium oxide dilution. Another study carried out in Italy including 14 centenarians found a significant correlation between BIA and fat-free mass evaluated using anthropometric tools. In one study, BIA showed a significant agreement with anthropometric measures of fat mass. In the same sample, sarcopenia and dehydration, evaluated with BIA, had a high prevalence.ConclusionBIA may be used for assessing body composition in centenarians, but research is limited to a few studies suggesting the need of future research in this area.

Birth Weight and Body Composition as Determined by Isotopic Dilution with Deuterium Oxide in 6- to 8-Year-Old South African Children.

Low and high birth weight (BW) are associated with obesity later in life; however, this association has not been extensively studied in African countries. This study determines the association between BW and body composition derived from deuterium oxide (D2O) dilution in 6- to 8-year-old South African children (n = 91; 40 boys, 51 girls). BW was recorded retrospectively from the children’s Road-to-Health cards. Weight and height were measured using standard procedures, and D2O dilution was used to determine total body water and, subsequently, to determine body fat. Fatness was classified using the McCarthy centiles, set at 2nd, 85th, and 95th (underfat, overfat and obese). BW correlated with body composition measures, such as body weight (r = 0.23, p = 0.03), height (r = 0.33, p < 0.001), and fat free mass (FFM; r = 0.27, p = 0.01). When multiple regression analysis was employed, BW significantly and positively associated with FFM (β = 0.24, p = 0.013; 95% CI: 0.032; 0.441) and fat mass (β = 0.21, p = 0.02, 95%CI: 0.001; 0.412) in girls and boys combined. A total of 13% of the children had a low BW, with 21% being overweight and 17% obese. More girls than boys were overweight and obese. Intervention strategies that promote healthy uterine growth for optimal BW are needed in order to curb the global obesity pandemic.

Total water intake guidelines are sufficient for optimal hydration in United States adults.

Recent studies suggest that 24-h urine osmolality (UOsm) for optimal water intake should be maintained < 500mmol·kg-1. The purpose of this study was to determine the total water intake (TWI) requirement for healthy adults to maintain optimal hydration as indicated by 24-h urine osmolality < 500mmol·kg-1. Twenty-four-hour UOsm was assessed in 49 men and 50 women residing in the United States (age: 41 ± 14 y, body mass index: 26.3 ± 5.2kg·m-2). TWI was assessed from 7-day water turnover, using a dilution of deuterium oxide, corrected for metabolic water production. The diagnostic accuracy of TWI to identify UOsm < 500mmol·kg-1 was evaluated using receiver operating characteristic (ROC) analysis in men and women separately. Twenty-four-hour UOsm was 482 ± 229 and 346 ± 182mmol·kg-1 and TWI was 3.57 ± 1.10L·d-1 and 3.20 ± 1.27L·d-1 in men and women, respectively. ROC analysis for TWI detecting 24-h UOsm < 500mmol·kg-1 in men yielded an area under the curve (AUC) of 77.4% with sensitivity, specificity, and threshold values of 83.3%, 64.5%, and 3.39L·d-1, respectively. The AUC was 82.4% in women with sensitivity, specificity, and threshold values of 85.7%, 72.1%, and 2.61L·d-1. Considering threshold values in men and women of 3.4L·d-1 and 2.6L·d-1, respectively, maintaining TWI in line with National Academy of Medicine guidelines of 3.7L·d-1 in men and 2.7L·d-1 in women should be sufficient for most individuals in the United States to maintain 24-h UOsm < 500mmol·kg-1.

Development of bioelectrical impedance-based equations for the prediction of body composition of Malawian adolescents aged 10–18 years: a cross-sectional study

ObjectivesThe accuracy of bioelectrical impedance analysis (BIA) depends on population-specific prediction equations and there is no population-specific equation for predicting fat-free mass (FFM) in Malawian adolescents. This study aimed at...

Body Composition Assessment in Mexican Children and Adolescents. Part 1: Comparisons between Skinfold-Thickness, Dual X-ray Absorptiometry, Air-Displacement Plethysmography, Deuterium Oxide Dilution, and Magnetic Resonance Imaging with the 4-C Model.

The evaluation of body composition (BC) is relevant in the evaluation of children’s health-disease states. Different methods and devices are used to estimate BC. The availability of methods and the clinical condition of the patient usually defines the ideal approach to be used. In this cross-sectional study, we evaluate the accuracy of different methods to estimate BC in Mexican children and adolescents, using the 4-C model as the reference. In a sample of 288 Mexican children and adolescents, 4-C body composition assessment, skinfold-thickness (SF), dual-energy X-ray absorptiometry (DXA), air displacement plethysmography (ADP), and deuterium dilution (D2O) were performed, along with MRI in a subsample (52 participants). The analysis of validity was performed by correlation analysis, linear regression, and the Bland–Altman method. All methods analyzed showed strong correlations for FM with 4-C values and between each other; however, DXA and MRI overestimated FM, whereas skinfolds and ADP under-estimated FM. Conclusion: The clinical assessment of BC by means of SF, ADP, DXA, MRI and D2O correlated well with the 4-C model and between them, providing evidence of their clinical validity and utility. The results from different methods are not interchangeable. Preference between methods may depend on their availability and the specific clinical setting.

Body composition from birth to 2 years in term healthy Indian infants measured by deuterium dilution: Effect of being born small for gestational age and early catch-up growth.

South Asian body composition is characterized by higher body fat at any given BMI. While this does not occur during fetal growth, it is important to understand if inappropriate fat accretion then begins in the first 2 years in Indian infants. The fat mass (FM) and fat-free mass (FFM) of healthy term newborns was evaluated at 12 days, 3.5 months, 1 year, and 2 years, by deuterium oxide (D2O) dilution. The effect of being born small versus appropriate for gestational age (SGA vs. AGA), and accelerated early growth pattern on FM and FFM accretion was also investigated. Newborns (262 total, 150 males) with mean birth weight of 2863 ± 418 g were enrolled. FM percentage (FM%) assessed by D2O in 144, 166, 81, and 115 infants at 12 days, 3.5 months, 1 year, and 2 years respectively, was11.6 ± 6.8, 21.1 ± 7.0, 17.9 ± 8.2 and 22.4 ± 9.5%. Boys had higher FFM at all ages, but FM% was similar in both sexes. Children born SGA had similar FM index (FMI) but a lower FFM index (FFMI) at 2 years compared with those born AGA. Infants with catch-up growth between 0 and 2 years had higher FMI at 2 years compared to those without. Infants in the present study had a lower FM% and FMI till 1 year of age in comparison to previous studies from other countries, but had an increase in adiposity between 1 and 2 years, whereas in previous studies FM% remained stable or declined between 1 and 2 years of age. There was an upward inflection in the curve of FM% and FMI between 1 and 2 years of age in the present study, which may represent an early adiposity rebound. Further longitudinal body composition data for Indian infants as well as those of other ethnicities but with low birth weight will clarify whether early accelerated growth pattern contributes to greater accrual of fat rather than lean mass during childhood.

Mid-upper arm circumference in pregnant women and birth weight in newborns as substitute for skinfold thickness: findings from the MAASTHI cohort study, India

BackgroundEstimating total body fat in public hospitals using gold-standard measurements such as air displacement plethysmography (ADP), deuterium oxide dilution, or dual-energy X-ray absorptiometry (DXA) is unaffordable, and it is challenging to use skinfold thickness. We aimed to identify the appropriate substitute marker for skinfold thickness to estimate total body fat in pregnant women and infants.MethodsThe study is part of a prospective cohort study titled MAASTHI in Bengaluru, from 2016 to 19. Anthropometric measurements such as body weight, head circumference, mid-upper arm circumference (MUAC), and skinfold thickness were measured in pregnant women between 14 and 36 weeks of gestational age; while measurements such as birth weight, head, chest, waist, hip, mid-upper arm circumference, and skinfold thickness were recorded for newborns. We calculated Kappa statistics to assess agreement between these anthropometric markers with skinfold thickness.ResultsWe found the highest amount of agreement between total skinfold thickness and MUAC (Kappa statistic, 0.42; 95 % CI 0.38–0.46) in pregnant women. For newborns, the highest agreement with total skinfold thickness was with birth weight (0.57; 95 % CI 0.52–0.60). Our results indicate that MUAC higher than 29.2 cm can serve as a suitable alternative to total skinfolds-based assessments for obesity screening in pregnancy in public facilities. Similarly, a birth weight cut-off of 3.45 kg can be considered for classifying obesity among newborns.ConclusionMid-upper arm circumference and birth weight can be used as markers of skinfold thickness, reflecting total body fat in pregnant women and the infant, respectively. These two anthropometric measurements could substitute for skinfold thickness in low- and middle-income urban India settings.

NUTRITIONAL STATUS IN CHILDREN WITH CANCER: COMPARISON OF DEUTERIUM OXIDE DILUTION WITH BIOELECTRIC IMPEDANCE ANALYSIS AND ANTHROPOMETRY

ABSTRACTObjective: To explore changes in the nutritional status of pediatric cancer patients before and after chemotherapy and evaluate the correlation between deuterium oxide dilution, bioelectric impedance analysis, and anthropometry for assessment of body composition.Methods: This study included 14 children (aged 5.6 to 13.6 years) and classified them as having hematologic or solid tumors. They had their body composition analyzed according to deuterium oxide, bioelectric impedance, and anthropometric measurements before the first chemotherapy cycle and after three and six months of therapy.Results: The patients in the hematologic tumor group had an increase in weight, height, body mass index, waist, hip, and arm circumference, subscapular skinfold thickness, and fat mass with the isotope dilution technique during chemotherapy. In the solid tumor group, the children showed a reduction in fat-free mass when assessed by bioimpedance analysis. We found a positive correlation between the triceps skinfold thickness and fat mass determined by bioimpedance analysis and deuterium oxide. The arm muscle circumference correlated with the fat-free mass estimated by bioimpedance analysis and deuterium oxide.Conclusions: Patients with hematologic tumors had an increase in body weight, height, and fat mass, which was not identified in the solid tumor group. The positive correlation between anthropometry (triceps skinfold thickness and arm muscle circumference), deuterium oxide dilution, and bioelectric impedance analysis shows the applicability of anthropometry in clinical practice.

Relevance of body mass index and bioelectrical impedance analysis vs. deuterium dilution technique to assess excess of fat among young adults

ABSTRACT Our study aimed to assess the nutritional status by using body composition among young Tunisian adults through three measurement methods: body mass index (BMI), bioelectrical impedance analysis (BIA) and deuterium oxide dilution technique (2H2O) and to determine the accuracy of BMI and BIA in order to evaluate the overweight and obesity among young adults in Tunisia. Our study involved 144 young adults. Anthropometric parameters were measured. The fat mass percentage (%FM) was determined by 2H2O and BIA techniques. The analysis of deuterium enrichment was performed using a Fourier transform infrared spectrophotometer (FTIR). According to BMI, 26.4% of subjects were overweight and 5.5% were obese. The mean of %FM estimated by BIA was significantly higher than that determined by 2H2O (29.7 ± 7.7 vs. 26.3 ± 10.6, p < .0001). Consequently, the prevalence of overweight and obesity assessed by BIA was significantly higher than by 2H2O (51.4% vs. 34%, p < .0001). Using BMI, the prevalence of overweight and obesity was similar to that estimated by 2H2O (31.9% vs. 34%, p = 0.544). Compared to 2H2O, BIA overestimates the prevalence of overweight and obesity in young adults. On the other hand, the BMI showed an interesting correlation with the %FM determined by 2H2O.

Impact of litter size, supplementary milk replacer and housing on the body composition of piglets from hyper-prolific sows at weaning

The modern hyper-prolific sow gives birth to 17 live-born piglets on average. An alternative strategy to nurse sows and artificial rearing may be providing milk replacer while letting all the piglets stay with their dam. However, milk replacer is of lower nutritional quality than sow milk and may reduce the body fat content of piglets who use milk replacer to compensate for low suckling success due to competition at the udder. Therefore, the aim of this study was to investigate the body composition at weaning of two random sow-reared piglets per litter from 93 litters by using the deuterium oxide dilution technique. The piglets were part of large study with a 2×2×2 factorial design of either 14 or 17 piglets from day 1 (LS: LS14/LS17) with or without access to milk replacer (MILK: -MILK/+MILK) and reared by crated or loose-housed sows (HOUSING: CRATE/ LOOSE). From behavioral observations day 21 in +MILK, piglets were divided according to their frequency of drinking milk replacer and suckling (Nutrition Source). Increasing LS from 14 to 17 reduced the average daily gain from 258 to 228 g/d and body fat % from 14.4 to 12.7% (P<0.01). In a two-way interaction between LS and HOUSNG, the body fat percentage was lower (P=0.04) and the water percentage tended to be higher (P=0.07) in LS17 CRATE compared to the other treatments (i.e. LS17 LOOSE, LS14 CRATE and LOOSE). There was no effect of MILK on piglet composition day 28 (P>0.1). In +MILK, the Nutrition Source affected piglet body composition (P<0.05) as piglets with low suckling frequency (LOW) had lower body fat and higher water content compared to piglets who had high suckling frequency (SUCKLE). Unexpectedly, drinking milk replacer in addition to suckling (MIXED) did not increase piglet body fat content. Relying mainly on milk replacer (CUP) caused body fat and water contents to be intermediate to piglets with high (SUCKLE and MIXED) and low suckling frequency (LOW). In conclusion, LS had a clear impact on piglet growth and body composition at weaning. In contrast, supplementation of milk and housing had only negligible impact on litter performance. Some individual piglets that had low frequency of sow milk intake benefitted from milk supplementation. Loose housing appeared to benefit piglet body fat at weaning but this was due to a greater piglet mortality.

241 Metoclopramide induces low-level hyperprolactinemia to increase milk production in sows

Abstract Inadequate milk production by sows often limits the growth rate of piglets. A successful lactation requires prolactin (PRL)-induced differentiation of the alveolar epithelium within the mammary glands of sows between gestation days 90–110 (G90-110). We hypothesized that late gestational hyperprolactinemia in primiparous sows induced by feeding the dopamine antagonist metoclopramide (MET) would enhance mammary epithelial differentiation, milk yield, and piglet growth rate, and that these effects would carry over into a subsequent lactation. Twenty-six gilts were randomly assigned to receive either MET (n = 13, 0.8mg/kg) or vehicle (CON, n = 13) twice daily from G90-110. On G90, circulating PRL levels peaked 45 min after MET dosing (P &amp;lt; 0.001) then returned to baseline 3 h later. This response occurred daily out to G104 (P &amp;lt; 0.05). Treated gilts had increased alveolar lumen diameter on G110 (P &amp;lt; 0.05), though feed intake, body weight, and carcass fat percent were not different during pregnancy or lactation. Piglets born to treated sows had increased body weight and average daily gain on lactation days 14 and 21 (P &amp;lt; 0.05). Piglet milk intake was estimated from deuterium oxide dilution. While milk intake by piglets nursing MET sows was not statistically different from those nursing CON sows on day 21 of lactation (P = 0.18), there was a greater increase in milk consumption by piglets born to MET-treated sows between days 9 and 21 of lactation than for those in CON litters (P &amp;lt; 0.001). In one group of second parity sows, milk yield was increased during their second lactation with no additional treatment (P &amp;lt; 0.05) and their carcass fat dropped by 14% (P &amp;lt; 0.05). These findings demonstrate that MET-induced hyperprolactinemia in pigs during late pregnancy can increase milk yield and piglet growth rate, and this response can be sustained into a second lactation in some sows.

Total Energy Expenditure and Functional Status in Older Adults: A Doubly Labelled Water Study.

Higher total energy expenditure in free living conditions, regardless of any activity, has been strongly associated with a lower risk of mortality in healthy older adults. Also, a good performance in physical and functional tests is a marker of good functional prognosis. However, it is not yet clear what is the association between total energy expenditure and the performance in physical and functional tests. The objective of this study was to verify the association between the total energy expenditure of older adults measured by doubly labelled water and the performance in functional tests. Cross-sectional study. Fifty-six older people were recruited from health services linked to the participating institutions. Socio-demographic, anthropometric and clinical characteristics were assessed through the application of a structured questionnaire. Body composition was evaluated by isotopic dilution of deuterium oxide and functional status was assessed by the gait speed test, 6-minute walk test and handgrip strength. Total energy expenditure (GET) was assessed using the doubly labelled water method and the physical activity profile was verified using an activity monitor based on accelerometery. The results showed that the highest total energy expenditure correlated with the best performance in the gait speed tests (r = 0.266; p = 0.047), 6-minute walk test (r = 0.424; p = 0.001) and maximum handgrip strength (r = 0.478; p = 0.000). Multivariate regression analysis in a model adjusted for sex and fat-free mass revealed an association between total energy expenditure and the 6-minute walk test (ß = 1.790; t = 2.080; p = 0.044) and the number of sedentary events ( ß = 6.389; t = 2.147; p = 0.038). The results of this study suggest that, in clinical practice, older individuals with lower gait speed, worse performance in the 6-minute walk test and lower handgrip strength, may have lower total energy expenditure, being the stimulus for its increase important for the prevention of possible problems related to low energy expenditure.