TY - JOUR
T1 - A computational model to determine energy intake during weight loss
AU - Thomas, Diana M.
AU - Schoeller, Dale A.
AU - Redman, Leanne A.
AU - Martin, Corby K.
AU - Levine, James A.
AU - Heymsfield, Steven B.
PY - 2010/12/1
Y1 - 2010/12/1
N2 - Background: Energy intake (EI) during weight loss is difficult and costly to measure accurately. Objective: The objective was to develop and validate a computational energy balance differential equation model to determine individual EI during weight loss. Design: An algorithm was developed to quantify EI during weight loss based on a validated one-dimensional model for weight change. By using data from a 24-wk calorie-restriction study, we tested the validity of the EI model against 2 criterion measures: 1) EI quantified through food provision from weeks 0-4 and 4-12 and 2) EI quantified through changes in body energy stores [measured with dual-energy X-ray absorptiometry (DXA)] and energy expenditure [measured with doubly labeled water (DLW)] from weeks 4-12 and 12-24. Results: Compared with food provision, the mean (6SD) model errors were 41 ± 118 kcal/d and -22 ± 230 kcal/d from weeks 0-4 and 4-12, respectively. Compared with EI measured with DXA and DLW, the model errors were -71 ± 272 kcal/d and -48 ± 226 kcal/d from weeks 4-12 and 12-24, respectively. In every comparison, the mean error was never significantly different from zero (P values > 0.10). Furthermore, Bland and Altman analysis indicated that error variance did not differ significantly over amounts of EI (P values > 0.26). Almost all individual participants' values were within CI limits. Conclusion: The validity of the newly developed EI model was supported by experimental observations and can be used to determine an individual participant's EI during weight loss.
AB - Background: Energy intake (EI) during weight loss is difficult and costly to measure accurately. Objective: The objective was to develop and validate a computational energy balance differential equation model to determine individual EI during weight loss. Design: An algorithm was developed to quantify EI during weight loss based on a validated one-dimensional model for weight change. By using data from a 24-wk calorie-restriction study, we tested the validity of the EI model against 2 criterion measures: 1) EI quantified through food provision from weeks 0-4 and 4-12 and 2) EI quantified through changes in body energy stores [measured with dual-energy X-ray absorptiometry (DXA)] and energy expenditure [measured with doubly labeled water (DLW)] from weeks 4-12 and 12-24. Results: Compared with food provision, the mean (6SD) model errors were 41 ± 118 kcal/d and -22 ± 230 kcal/d from weeks 0-4 and 4-12, respectively. Compared with EI measured with DXA and DLW, the model errors were -71 ± 272 kcal/d and -48 ± 226 kcal/d from weeks 4-12 and 12-24, respectively. In every comparison, the mean error was never significantly different from zero (P values > 0.10). Furthermore, Bland and Altman analysis indicated that error variance did not differ significantly over amounts of EI (P values > 0.26). Almost all individual participants' values were within CI limits. Conclusion: The validity of the newly developed EI model was supported by experimental observations and can be used to determine an individual participant's EI during weight loss.
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U2 - 10.3945/ajcn.2010.29687
DO - 10.3945/ajcn.2010.29687
M3 - Article
C2 - 20962159
AN - SCOPUS:78651272116
SN - 0002-9165
VL - 92
SP - 1326
EP - 1331
JO - American Journal of Clinical Nutrition
JF - American Journal of Clinical Nutrition
IS - 6
ER -