Adult Weight Management

Healthy Non-Obese Adults (2010-2012)

Citation:

Mifflin MD, St Jeor ST, Hill LA, Scott BJ, Daugherty SA, Koh YO. A new predictive equation for resting energy expenditure in healthy individuals. Am J Clin Nutr. 1990 Feb; 51 (2): 241-247.

PubMed ID: 2305711
 
Study Design:
Cross-Sectional Study
Class:
D - Click here for explanation of classification scheme.
Quality Rating:
Positive POSITIVE: See Quality Criteria Checklist below.
Research Purpose:
  • Mathematically derive a predictive equation for REE based on a sample of 498 healthy normal-weight and obese individuals
  • Assess the usefulness of the more recent body composition measures of body composition (%BF) and distribution (WHR) in predicting REE
  • Assess the predictive value as well as overall practicality of the new equations compared with those currently being applied.
Inclusion Criteria:
  • Recruitment by a 2x2x5 factorial design where sex and weight were stratified by five different age groups according to decade
  • Bias toward the working class (defined as either the subject or spouse being employed at least half-time for the past year)
  • Understand and give written consent
  • Either the subject or spouse being employed the equivalent of half-time
  • Good health with less than one sick day per month for the past year
  • No major current illnesses or psychological problems
  • Extreme underweight (<80% IBW) or morbidly obese (>180% IBW).
Exclusion Criteria:
  • Refusal to consent
  • In poor health.
Description of Study Protocol:

Recruitment   

  • Data from subjects enrolled in the five-year RENO Diet-Heart study
  • Recruitment by a 2x2x5 factorial design where sex and weight were stratified by five different age groups according to decade
  • Bias toward working-class individuals.

Design

Cross-sectional study

Blinding used

Not applicable

Intervention

Not applicable

Statistical Analysis

  • Pearson correlation coefficients and simple and stepwise multiple-regression analyses to assess relationships between measured resting energy expenditure and weight, height, age, sex, fat-free mass (FFM), percent ideal body weight ( percent IBW), body mass index (BMI) and waist-hip ratio (WHR)
    • Predictive equations were developed and compared with commonly used equations
    • Sex was entered as a dummy variable
    • Included estimates of FFM
    • Data for 482 of 498 subjects.
Data Collection Summary:

Timing of Measurements

One measurement time

Dependent variables

  • Measured resting energy expenditure (REE) [(VO2, liters per minute), CO2 (liters per minute; ml/kg per minute), RER, ventilation (liters per minute)]
    • IC type: Metabolic measurement care with a canopy hood; Standard computer programs converted O2 and CO2 gas exchanged into REE
    • Rest before measure: Relaxed, supine position with a standardized relaxation tape
    • Measurement length: Approximately 20 minutes per subject; measurements repeated on all subjects until a three-minute steady state was achieved
    • Fasting length: Overnight
    • Exercise conditioning 24 prior to test? Abstain from exercise 12 hours before the test
    • Room temp: Not reported
    • No. of measures were they repeated? Only one day for obtaining IC measurement, described in measurement length
    • Coefficient of variation? None reported
    • Equipment of Calibration: “SF was key to our successful measurement by his training of our staff and high quality research methodology commitment”
    • Training of measurer? Trained and certified nutritionists using a standardized protocol
    • Subject training of measuring process? None reported
    • Other: Refrain from smoking more than one hour before testing but for 12 hours if possible
    • Monitored heart rate? Not reported
    • Body temperature? Not reported
  • Predicted REE.

Independent variables

  • Age
  • Weight: Measured to nearest 0.55kg on standard physician's beam scale in street clothes and without shoes
  • Height: measured to nearest 0.63cm on standardized wall-mounted height board without shoes and using standard protocol
  • Percent ideal body weight (%IBW): Determined using 1959 Metropolitan tables
  • BMI: kg/m2
  • FFM: Body fat (BF) determined from three skinfolds using Jockson-Pollock method; FFM calculated by weight (kg) - fat (kg) where fat (kg) is weight (kg) x %BF
  • Waist: Hip ratio: Waist measured at obvious indentation or smallest circumference at mid-torso; hip measurement taken at widest circumference on the torso.
Description of Actual Data Sample:
  • Initial N: N=508
  • Attrition (final N): N=498 (N=247 females; N=251 males) (10 dropouts due to inability to obtain REE measurements)
  • Age:
    • Females: 44.6±14.0 years (range: 20-76)
    • Males: 44.4+14.3 years (range: 19-78)
  • Ethnicity: Not reported
  • Other relevant demographics: None reported
  • Anthropometrics:
    • <100% Ideal Body Weight
  Women N=52 Mean±SD Men N=26 Mean±SD

Weight, kg

54.9±4.5 68.5±5.8

Height, cm

164.8±5.2 178.9±6.3

Percent IBW

92.8±4.4 94.8±4.0

BMI

20.3±1.0 21.5±0.9

W:H ratio

0.73±0.05 0.86±0.04

Percent Body fat

30.0±4.5 10.7±5.3
  • 100-119% Ideal Body Weight
   Women N=83 Mean±SD  Men N=103 Mean±SD

Weight, kg

 63.7±5.5  80.2±7.2

Height, cm

 163.9±5.8  178.5±7.1

Percent IBW

 108.8±5.9  110.9±5.2

BMI

 23.8±1.3  25.2±1.1

W:H ratio

 0.76±0.06  0.90±0.05

Percent Body fat

 28.7±5.5  17.6±4.9
  • 120-139% Ideal Body Weight
  Women N=61 Mean±SD Men N=82 Mean±SD

Weight, kg

76.2±6.6 92.2±7.3

Height, cm

164.7±6.4 178.0±6.3
Percent IBW 129.5±6.4 128.5±5.4

BMI

28.4±1.5 29.1±1.2

W:H ratio

0.80±0.07 0.93±0.05

Percent Body fat

36.1±4.5 21.9±5.1
  • =140% Ideal Body Weight
  Women N=51 Mean±SD Men N=40 Mean±SD

Weight, kg

 89.4±11.0  108.7±13.1

Height, cm

 163.7±7.7  178.3±7.3
Percent IBW  153.1±11.3  151.9±10.8

BMI

 33.5±2.5  34.4±2.4

W:H ratio

 0.82±0.07  0.96±0.06

Percent Body fat

 41.5±5.5  28.4±6.0
  • Unplanned exposure factor: N=1 individual was <80% IBW and N=2 were >180% IBW.
  •  Location: University of Nevada, Reno NV.
Summary of Results:

Pearson Correlation Coefficients with REE

  • Percent FFM was shown to correlate most highly with REE (R=0.80) for the entire group of males and females
    • FFM and weight were correlated (R=0.79)
    • FFM and height were correlated (R=0.81)
    • Sex and FFM were correlated (R=0.83)
  • Weight: 0.72607
  • Height: 0.68669
  • Age: -0.26104
  • Percent IBW: 0.35497
  • WHR: 0.54599.

Stepwise multiple regression for predictive equations

  • Stepwise multiple regression analysis including all variables yielded a predictive equation for REE in which FFM alone yielded an R2 value of 0.64
    • The stepwise addition of weight, age, height, and WHR increased the R2 value to 0.70
    • The remaining variables (sex,  percent IBW and BMI) did not contribute further to the predictive value of the equation
  • To develop a practical equation for predicting REE, FFM was excluded and weight alone was used: Weight alone yielded a R2 value of 0.56
    • The addition of percent IBW, age and sex increased the correlation to R2=0.71
    • Further, a more practical equation that included weight, height and age had a predictive value that equaled equations containing FFM and percent IBW (R2=0.71
      • REE=9.88 x weight+6.25 x height-4.92 x age+166 x sex (males, one; females, zero)-161
  • The R2 value of approximately 0.7 seemed to be a barrier above which REE could not be more accurately predicted, suggesting that there is a variability of >30% in REE that cannot be explained on the basis of the variables assessed in this study... [possibly] due to individual differences in genetically determined or acquired metabolic efficiency.
  • The effects of sex and obesity on REE were extensively explored by analyzing men and women, normal (<120% IBW) and overweight (≥120% IBW)  individuals separately. No significant differences were observed between simple regression lines for FFM in men and women within the range of values studied (males R2=0.44; females R2=0.36).
  • A stepwise multiple-regression analyses of subsets of the population based on sex and %IBW did not reveal any relationships or equations surpassing the predictive value of the equation considering measured weight and height and age.
  • The R2 of 0.71 is obtained in using gender-specific equation of Mifflin-Jeor (above)
  • Proposed equations (MSJE)  for males and females after simplification by rounding of numbers:
    • Females: REE=10 x weight (kg)+6.25 x height (cm)-5 x age (years)-161
    • Males: REE=10 x weight (kg) + 6.25 x height (cm)-5 x age (years)+5.

Clinical

  • Measured REE for all women (N=247) had a mean of 1,349±214kcal per day and a range of 927-2,216kcal per day
    • MSJE equation predicted 1,348+179kcal per day
  • Measured REE for all men (N=251) had a mean of 1,776±297kcal per day and a range of 1,030-2,849kcal per day.
    • MSJE equation predicted 1,775+192kcal per day.

Correlation between measured and other predictive equations:

  • Mifflin-St Jeor (this study) had the best predictors of REE with the Owen equations having the least mean difference from measured REE (-4% in females and 0.1% in males)
  • HB significantly overpredicted REE in studies population (paired T-tests on individual means, P<0.01) by 5% and Cunningham equations significantly overpredicted REE in study population by 14-15% (by paired T-tests on individual means, P<0.01).
Author Conclusion:

As stated by the author in body of report:

  • The relationships between REE and several variables were studied to derive predictive equations for practical, clinical use in weight management today. The result of this process was to confirm EE is determined largely by FFM but is highly correlated with total body weight as well; adding height, age and sex builds on the predictive value of weight in determining REE
  • Previous findings suggest HB equation overpredicts measured REE by an average of >15% in modern populations; in our study, the are marked differences between means for weights and ages.
  • Our equations are limited to their derivation from our study population, their clinical utility can be assessed by testing in other populations. Their strength and significance lie in
    • Derivation from a larger, modern-day population (stratified by age, weight and sex)
    • Use of advanced equipment and technology for the measurement of actual REE
    • A reasonably high correlation between REE and weight, height and age (R2=0.71)
  • Direct metabolic measurements are preferable in individuals where a precise determination of REE is indicated. Other components of 24-EE (physical activity and thermic effect of food should be studied to assess more accurately the individual total daily caloric requirements.
  • 30% unexplained variability in REE observed should be studied further.
Funding Source:
Government: NIDDK, NIH
University/Hospital: University of Nevada School of Medicine, and the Graduate School University of Nevada,
Reviewer Comments:

Strengths

  • Large sample size in comparison to other studies and stratified for age, sex and weight
  • Standardized measurements.

Generalizability/Weaknesses

  • Generalizability to study population with potential clinical utility with further validation testing
  • Potential for small IC inaccuracy due to lack of subject training on the procedure.
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
  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
  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
  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
  4. Is the intervention or procedure feasible? (NA for some epidemiological studies) Yes
 
Validity Questions
  1. Was the research question clearly stated? Yes
1. Was the research question clearly stated? Yes
  1.1. Was (were) the specific intervention(s) or procedure(s) [independent variable(s)] identified? Yes
  1.1. 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
  1.2. Was (were) the outcome(s) [dependent variable(s)] clearly indicated? Yes
  1.3. Were the target population and setting specified? Yes
  1.3. Were the target population and setting specified? Yes
  2. Was the selection of study subjects/patients free from bias? 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
  2.1. 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
  2.2. Were criteria applied equally to all study groups? Yes
  2.3. Were health, demographics, and other characteristics of subjects described? 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
  2.4. Were the subjects/patients a representative sample of the relevant population? Yes
  3. Were study groups comparable? 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
  3.1. 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? N/A
  3.2. Were distribution of disease status, prognostic factors, and other factors (e.g., demographics) similar across study groups at baseline? N/A
  3.3. Were concurrent controls or comparisons used? (Concurrent preferred over historical control or comparison groups.) N/A
  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
  3.4. 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.) 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.) Yes
  3.6. If diagnostic test, was there an independent blind comparison with an appropriate reference standard (e.g., "gold standard")? 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. Was method of handling withdrawals described? Yes
  4.1. Were follow-up methods described and the same for all groups? Yes
  4.1. Were follow-up methods described and the same for all groups? Yes
  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
  4.2. 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? Yes
  4.3. Were all enrolled subjects/patients (in the original sample) accounted for? Yes
  4.4. Were reasons for withdrawals similar across groups? N/A
  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
  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. 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
  5.1. 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
  5.2. 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
  5.3. 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
  5.4. 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
  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. 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
  6.1. 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
  6.2. 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
  6.3. 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
  6.4. 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
  6.5. Were co-interventions (e.g., ancillary treatments, other therapies) described? N/A
  6.6. Were extra or unplanned treatments 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
  6.7. 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
  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. 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
  7.1. 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
  7.2. 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
  7.3. 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
  7.4. 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
  7.5. 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
  7.6. Were other factors accounted for (measured) that could affect outcomes? Yes
  7.7. Were the measurements conducted consistently across groups? 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. 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
  8.1. 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
  8.2. 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
  8.3. 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
  8.4. 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
  8.5. 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
  8.6. 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
  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. Are conclusions supported by results with biases and limitations taken into consideration? Yes
  9.1. Is there a discussion of findings? Yes
  9.1. Is there a discussion of findings? Yes
  9.2. Are biases and study limitations identified and discussed? 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. Is bias due to study's funding or sponsorship unlikely? Yes
  10.1. Were sources of funding and investigators' affiliations described? Yes
  10.1. Were sources of funding and investigators' affiliations described? Yes
  10.2. Was the study free from apparent conflict of interest? Yes
  10.2. Was the study free from apparent conflict of interest? Yes