Adult Weight Management

Healthy Non-Obese Adults (2010-2012)


Owen OE, Holup JL, D'Alessio DA, Craig ES, Polansky M, Smalley KJ, Kavle EC, Bushman MC, Owen LR, Mozzoli MA, et al. A reappraisal of the caloric requirements of men. Am J Clin Nutr. 1987; 46: 875-885.

PubMed ID: 3687821
Study Design:
Cross-Sectional Study
D - Click here for explanation of classification scheme.
Quality Rating:
Positive POSITIVE: See Quality Criteria Checklist below.
Research Purpose:
  • To reappraise the caloric requirements of healthy lean and obese men from a mixed population in the US
  • To analyze the effects of age on RMR and analyze the relationship of predicted to actual metabolic rates.
Inclusion Criteria:
  • Understand and give written consent
  • Eating balanced meals
  • Stable weights for at least one month
  • Not taking any medications
  • No evidence of physical or mental disease
  • Physical activities were approximately comparable day-to-day.
Exclusion Criteria:
  • Refusal to consent
  • Professional or world-class athletes
  • Unable to use metabolic equipment properly.
Description of Study Protocol:


Volunteers selected after initial screening process; other recruitment procedures not described


Cross-sectional study

Blinding used 

Not applicable


Not applicable

Statistical Analysis

  • Pearson’s coefficient of correlation, simple regressions, stepwise multiple regressions used to assess relationships among RMR and weight, age, height, body surface area (BSA), body mass index (BMI), lean body mass (LBM), body cell mass (BCM), fat-free mass by densitometry (FFMD), fat mass by densitometry (FATMD), fat-free mass by skinfolds (FFMSF) and fat mass by skinfolds (FMSF).
  • Statistical differences in the abilities of the regression lines for weight, FFMD or FFMSF for predicting RMR was calculated using the partial F test for multiple regression analysis
  • A T-test assuming unequal variances was used to evaluate derived regression lines in analyses of lean and obese men separately and in combinations
  • Resistant regression lines reflect trends in nonprotein RQ, and CHO, fat and protein quantity
  • Measured RMRs and RMRs calculated from the Harris-Benedict equation were plotted against age to further evaluate the effects of age on RMR and to analyze the relationship of predicted to actual metabolic rates.
Data Collection Summary:

Timing of Measurements

One measurement time

Volunteers completed a routine day of activity, at 19:00 hours they ate a balance CHO, fat and protein meal providing ample calories; encouraged to go to bed at 22:00 and RMR was measured at 08:00 the next a.m.

Dependent variables

  • Measured REE [(VO2, liters per minute), CO2 (liters per minute; ml/kg per minute), RQ, non-protein RQ]
    • IC type: Use of mouth piece and nose clip
    • Rest before measure: Semi-supine position at complete bed rest for at least 30 minutes before the resting studies were done
    • Measurement length: 10 minutes; first four to five minutes used to clear the machine of room air; last five to six minutes used for recording/calculating O2 consumption, CO2 production and RQ
    • Fasting length: 12- to 13-hour overnight fast
    • Exercise conditioning 24 prior to test? Comparable from day-to-day
    • Room temp: 22-24 degrees C; humidity was approximately 33%
    • No. of measures and were they repeated? Each value was mean of five or six one-minute values; two or three baseline line values were determined at 15-minute intervals
    • Coefficient of variation? None reported
    • Equipment of Calibration: Yes, before and during each study
    • Training of measurer? Standard protocol
    • Subject training of measuring process?: Yes
    • Monitored heart rate? Yes
    • Body temperature? Yes.

 Independent variables

  • Age
  • Height: Barefoot
  • Weight: Barefoot and in light clothes
  • Body mass index (BMI): kg/m2
  • Body cell mass
  • Abdominal:hip ratio (A:H): Calculated from the circumference of the waist measured at a point through the upper one-third of the distance between the xiphoid process and the umbilicus divided by the circumference of the hips measured at a point 4cm below the superior anterior iliac process
  • Body composition: To determine fat mass and fat-free mass
    • Densitometric analysis:
      Underwater weighing was conducted in a 5x5x5½ tank with a light metal chair with a 10-pound weighted belt suspended from a Chatillion 15kg scale
      Weighing procedure repeated six or more times until three similar readings within 25g were obtained. Residual lung volume determined by the N washout technique.
    • Skinfold thicknesses obtained using a Lange caliper; had a constant tension of 10g/mm2 and measurements were taken on the right side of the body at eight sites to nearest 0.5mm and three skinfolds used for calculations to obtain body density data (chest, abdomen and thigh)
  • Predicted REE using HB, Mayo Foundation, Cunningham.

Control variables

Lean (≤30kg/m2) vs. obese (>30kg/m2)



Description of Actual Data Sample:
  • Initial N: Not given
  • Final N: N=60 males
  • Age: 38±15.6 years (range 18-82)
  • Ethnicity: Caucasian, "Negro" and "Oriental" volunteers
  • Other relevant demographics: Broad social, economic, educational and employment backgrounds
  • Anthropometrics:
  Mean±SD Range
Height, cm 175±6.9 163-188
Weight, kg 86.6±23.8 59.8-171.4
BSA 2.01±0.24 1.64-2.81
BMI 28.2±7.5 20.4-58.7
FFMD 6.0±11.0 45.2-97.9
FATMD 20.6±15.5 3.9-89.9


64.9±10.2 45.4-105.3


19.1±12.1 4.4-66.1
LBM 61.0±8.7 44.6-81.3
BCM 32.1±5.3 20.7-44.3

A:H ratio

0.70±0.67 0.84-1.10

BSA=body surface area; BMI=body mass index; LMB=lean body mass, BCM=body cell mass, FFMD=fat-free mass by densitometry, FATMD=fat mass by densitometry, FFMSF=fat-free mass by skinfolds, FATMSF=fat mass by skinfolds, A:H ratio=abdominal:hip ratio.

  • Location: Temple University, Philadelphia PA.
Summary of Results:

Pearson Correlation Coefficients with RMR:

  • Age: -0.31
  • Weight: 0.75
  • Height: 0.28
  • BSA: 0.75
  • BMI: 0.68
  • LBM: 0.74
  • BCM: 0.72
  • FFMD: 0.76
  • FATMD: 0.61
  • FFMSF: 0.78
  • FATMSF: 0.55
  • A:H: 0.22
  • Body composition variables reflecting active protoplasmic tissue such as weight, BSA, LBM, BCM, FFMD and FFMSF were all highly interrelated (r>0.85)
  • Since fat-free mass skinfold measurements (FFMSF) or fat-free mass-densitometry (FFMD) were highly correlated (R=0.97), researchers were unable to distinguish the best predictor
  • The influence of age was statistically insignificant and no effect of the abdominal:hip ratio
  • Body weight is most accurate, easily determined variable, and highly correlated with other measurements of active protoplasmic tissue (r>0.85)and highly correlated with RMR (R=0.75).


Resting energy expenditure: The measured RMR varied from 1,237-2,713kcal per 24-hours and related to body size.

Lean and obese regression  

Slopes of regression lines for RMR and weight for lean and obese men were statistically indistinguishable. A single regression line with 95% confidence limits was developed (18-29%).

Correlation between Owen predictions, HB, Mayo, Robertson-Reid, and Cunningham   

  • New Owen prediction equation ±1SD vs. predicted RMR was 0.00±215kcal per 24 hours
  • HB, Mayo Foundation, and Cunningham regression formulas or tables systematically overestimated RMR by 113±245, 99±218, and 56±224kcal per 24-hours, respectively
  • Robertson-Reid underestimated RMR by 42±213kcal per 24 hours
  • Over and underestimations were age dependent. The equation of the regression line is 118%-0.28 years. HB equation overestimates the RMR of young individuals and underestimates the RMR of males >64 years. On the average HB equation overestimates RMR by 9.2% in people <50 years and underestimates RMR by 0.8% in men >50 years.


  • The influence of gender on RMR is eliminated when fat-free mass by densitometry or skinfold thickness is used as the variable
  • The influence of gender on body composition (body weight, fat-free mass and fat mass) for women and men (using Owens previously published data on women). The slopes of the fat masses compared with the fat-free masses are statistically different (P<0.05) for women and men.

Dietary Data

There was a continuum for caloric requirements from the lowest to highest weights among lean and obese men. The quantities of individual macronutrients (CHO, fat, pro) oxidized did not increase parallel to weights. The non-protein respiratory quotient decreases as body weight increases.

Author Conclusion:

As stated by the author in body of report:

  • In our study, the body compositional variables reflecting active protoplasmic tissue such as WT, BSA, BMI, LBM, FFMD and FFMSF are all highly interrelated
  • The prediction equation may over- or underestimate the measured RMR by 18-29%. This broad range of RMR per unit mass of both lean and obese men conclusively demonstrates that metabolic efficiency is neither necessarily nor exclusively related to obesity
  • The influence of age on the RMR of healthy women (-2.9±2.3 age in years) and men (-3.3±1.8 age in years) was present but too small to be statistically significant
  • Usefulness of any RMR prediction equation derived from a population with large 95% confidence limits is questionable. Metabolic requirements of humans should be measured rather than predicted
  • Adult women have more stored, relatively inert triglyceride than men per unit body mass. Slopes of the RMR regression lines for women and men are different when weight is used as the variable but there is no difference in the slope when FFM is used. [Hence] the influence of sex is negated when fat-free mass is used to calculate the predicted RMR
  • Body fat distribution does not influence RMR.
Funding Source:
Government: US PHS, NIH
University/Hospital: Temple University School of Medicine, Temple University
Reviewer Comments:


  • Multi-ethnic groups represented-Caucasian, Negro, Oriental with broad social, economic, educational and employment backgrounds
  • Measurement standardized for optimum RMR conditions
  • Fat-free mass measured by densiometry and skinfolds.


  • Researcher selected participants after initial screening evaluations
  • Did not identify number in each ethnic group
  • Limited number of older adults; Ddd not perform a power analysis on small difference between age on the RMR of healthy women and men
  • Study biases include
    • Unable to determine who performed IC measurements
    • An intervening variable not measured smoking and body temperature
    • Did not analyze measured vs. predicted differences by weight classification. Group mean error differences excluding obese weight classifications were recalculated and found at the end of the Evidence Summary.
Quality Criteria Checklist: Primary Research
Relevance Questions
  1. Would implementing the studied intervention or procedure (if found successful) result in improved outcomes for the patients/clients/population group? (Not Applicable for some epidemiological studies) Yes
  2. Did the authors study an outcome (dependent variable) or topic that the patients/clients/population group would care about? Yes
  3. Is the focus of the intervention or procedure (independent variable) or topic of study a common issue of concern to dieteticspractice? Yes
  4. Is the intervention or procedure feasible? (NA for some epidemiological studies) Yes
Validity Questions
1. Was the research question clearly stated? Yes
  1.1. Was (were) the specific intervention(s) or procedure(s) [independent variable(s)] identified? Yes
  1.2. Was (were) the outcome(s) [dependent variable(s)] clearly indicated? Yes
  1.3. Were the target population and setting specified? Yes
2. Was the selection of study subjects/patients free from bias? Yes
  2.1. Were inclusion/exclusion criteria specified (e.g., risk, point in disease progression, diagnostic or prognosis criteria), and with sufficient detail and without omitting criteria critical to the study? Yes
  2.2. Were criteria applied equally to all study groups? Yes
  2.3. Were health, demographics, and other characteristics of subjects described? Yes
  2.4. Were the subjects/patients a representative sample of the relevant population? Yes
3. Were study groups comparable? Yes
  3.1. Was the method of assigning subjects/patients to groups described and unbiased? (Method of randomization identified if RCT) N/A
  3.2. Were distribution of disease status, prognostic factors, and other factors (e.g., demographics) similar across study groups at baseline? ???
  3.3. Were concurrent controls or comparisons used? (Concurrent preferred over historical control or comparison groups.) N/A
  3.4. If cohort study or cross-sectional study, were groups comparable on important confounding factors and/or were preexisting differences accounted for by using appropriate adjustments in statistical analysis? Yes
  3.5. If case control study, were potential confounding factors comparable for cases and controls? (If case series or trial with subjects serving as own control, this criterion is not applicable.) N/A
  3.6. If diagnostic test, was there an independent blind comparison with an appropriate reference standard (e.g., "gold standard")? N/A
4. Was method of handling withdrawals described? Yes
  4.1. Were follow-up methods described and the same for all groups? N/A
  4.2. Was the number, characteristics of withdrawals (i.e., dropouts, lost to follow up, attrition rate) and/or response rate (cross-sectional studies) described for each group? (Follow up goal for a strong study is 80%.) Yes
  4.3. Were all enrolled subjects/patients (in the original sample) accounted for? ???
  4.4. Were reasons for withdrawals similar across groups? N/A
  4.5. If diagnostic test, was decision to perform reference test not dependent on results of test under study? N/A
5. Was blinding used to prevent introduction of bias? N/A
  5.1. In intervention study, were subjects, clinicians/practitioners, and investigators blinded to treatment group, as appropriate? N/A
  5.2. Were data collectors blinded for outcomes assessment? (If outcome is measured using an objective test, such as a lab value, this criterion is assumed to be met.) N/A
  5.3. In cohort study or cross-sectional study, were measurements of outcomes and risk factors blinded? N/A
  5.4. In case control study, was case definition explicit and case ascertainment not influenced by exposure status? N/A
  5.5. In diagnostic study, were test results blinded to patient history and other test results? N/A
6. Were intervention/therapeutic regimens/exposure factor or procedure and any comparison(s) described in detail? Were interveningfactors described? Yes
  6.1. In RCT or other intervention trial, were protocols described for all regimens studied? N/A
  6.2. In observational study, were interventions, study settings, and clinicians/provider described? Yes
  6.3. Was the intensity and duration of the intervention or exposure factor sufficient to produce a meaningful effect? Yes
  6.4. Was the amount of exposure and, if relevant, subject/patient compliance measured? Yes
  6.5. Were co-interventions (e.g., ancillary treatments, other therapies) described? N/A
  6.6. Were extra or unplanned treatments described? N/A
  6.7. Was the information for 6.4, 6.5, and 6.6 assessed the same way for all groups? N/A
  6.8. In diagnostic study, were details of test administration and replication sufficient? N/A
7. Were outcomes clearly defined and the measurements valid and reliable? Yes
  7.1. Were primary and secondary endpoints described and relevant to the question? Yes
  7.2. Were nutrition measures appropriate to question and outcomes of concern? Yes
  7.3. Was the period of follow-up long enough for important outcome(s) to occur? Yes
  7.4. Were the observations and measurements based on standard, valid, and reliable data collection instruments/tests/procedures? Yes
  7.5. Was the measurement of effect at an appropriate level of precision? Yes
  7.6. Were other factors accounted for (measured) that could affect outcomes? Yes
  7.7. Were the measurements conducted consistently across groups? Yes
8. Was the statistical analysis appropriate for the study design and type of outcome indicators? Yes
  8.1. Were statistical analyses adequately described and the results reported appropriately? Yes
  8.2. Were correct statistical tests used and assumptions of test not violated? Yes
  8.3. Were statistics reported with levels of significance and/or confidence intervals? Yes
  8.4. Was "intent to treat" analysis of outcomes done (and as appropriate, was there an analysis of outcomes for those maximally exposed or a dose-response analysis)? N/A
  8.5. Were adequate adjustments made for effects of confounding factors that might have affected the outcomes (e.g., multivariate analyses)? Yes
  8.6. Was clinical significance as well as statistical significance reported? Yes
  8.7. If negative findings, was a power calculation reported to address type 2 error? N/A
9. Are conclusions supported by results with biases and limitations taken into consideration? Yes
  9.1. Is there a discussion of findings? Yes
  9.2. Are biases and study limitations identified and discussed? Yes
10. Is bias due to study's funding or sponsorship unlikely? Yes
  10.1. Were sources of funding and investigators' affiliations described? Yes
  10.2. Was the study free from apparent conflict of interest? Yes