BACKGROUND: While recent studies in humans indicate that fat-free mass (FFM) is closely associated with energy intake (EI) when in energy balance, associations between fat mass (FM) and EI are inconsistent. OBJECTIVES: The present study used a cross-sectional design to examine the indirect and direct effects of FFM, FM and resting metabolic rate (RMR) on EI in individuals at or close to energy balance. METHODS: Data for 242 individuals (114 males; 128 females; BMI = 25.7 ± 4.9 kg/m2) were collated from the non-intervention baseline conditions of five studies employing common measures of body composition (air-displacement plethysmography), RMR (indirect calorimetry) and psychometric measures of eating behaviours (Dutch Eating Behaviour Questionnaire). Daily EI (weighed dietary records) and energy expenditure (flex heart rate) were measured for 6-7 days. Sub-analyses were conducted in 71 individuals who had additional measures of body composition (dual-energy X-ray absorptiometry) and fasting glucose, insulin and leptin. RESULTS: After adjusting for age, sex and study, linear regression and mediation analyses indicated that the effect of FFM on EI was mediated by RMR (P < 0.05). FM also independently predicted EI, with path analysis indicating a positive indirect association (mediated by RMR; P < 0.05), and a stronger direct negative association (P < 0.05). Leptin, insulin and insulin resistance failed to predict EI, but cognitive restraint was a determinant of EI and partially mediated the association between FM and EI (P < 0.05). CONCLUSIONS: While the association between FFM and EI was mediated by RMR, FM influenced EI via two separate and opposing pathways; an indirect 'excitatory' effect (again, mediated by RMR), and a stronger direct 'inhibitory' effect. Psychological factors such as cognitive restraint remain robust predictors of EI when considered alongside physiological determinants of EI, and indeed, have the potential to play a mediating role in the overall expression of EI.
BACKGROUND: While recent studies in humans indicate that fat-free mass (FFM) is closely associated with energy intake (EI) when in energy balance, associations between fat mass (FM) and EI are inconsistent. OBJECTIVES: The present study used a cross-sectional design to examine the indirect and direct effects of FFM, FM and resting metabolic rate (RMR) on EI in individuals at or close to energy balance. METHODS: Data for 242 individuals (114 males; 128 females; BMI = 25.7 ± 4.9 kg/m2) were collated from the non-intervention baseline conditions of five studies employing common measures of body composition (air-displacement plethysmography), RMR (indirect calorimetry) and psychometric measures of eating behaviours (Dutch Eating Behaviour Questionnaire). Daily EI (weighed dietary records) and energy expenditure (flex heart rate) were measured for 6-7 days. Sub-analyses were conducted in 71 individuals who had additional measures of body composition (dual-energy X-ray absorptiometry) and fasting glucose, insulin and leptin. RESULTS: After adjusting for age, sex and study, linear regression and mediation analyses indicated that the effect of FFM on EI was mediated by RMR (P < 0.05). FM also independently predicted EI, with path analysis indicating a positive indirect association (mediated by RMR; P < 0.05), and a stronger direct negative association (P < 0.05). Leptin, insulin and insulin resistance failed to predict EI, but cognitive restraint was a determinant of EI and partially mediated the association between FM and EI (P < 0.05). CONCLUSIONS: While the association between FFM and EI was mediated by RMR, FM influenced EI via two separate and opposing pathways; an indirect 'excitatory' effect (again, mediated by RMR), and a stronger direct 'inhibitory' effect. Psychological factors such as cognitive restraint remain robust predictors of EI when considered alongside physiological determinants of EI, and indeed, have the potential to play a mediating role in the overall expression of EI.
Authors: Emma J Stinson; Alexis L Graham; Marie S Thearle; Marci E Gluck; Jonathan Krakoff; Paolo Piaggi Journal: Int J Obes (Lond) Date: 2019-01-16 Impact factor: 5.095
Authors: Nicole Fearnbach; Amanda E Staiano; Neil M Johannsen; Daniel S Hsia; Robbie A Beyl; Owen T Carmichael; Corby K Martin Journal: Nutrients Date: 2022-01-05 Impact factor: 5.717
Authors: Guillermo Sanchez-Delgado; Francisco M Acosta; Borja Martinez-Tellez; Graham Finlayson; Catherine Gibbons; Idoia Labayen; Jose M Llamas-Elvira; Angel Gil; John E Blundell; Jonatan R Ruiz Journal: Am J Clin Nutr Date: 2020-02-01 Impact factor: 7.045