Body Fatness Influences Associations of Body Composition and Energy Expenditure with Energy Intake in Healthy Women

Abstract

This study aimed to investigate the influence of body fatness on the associations of body composition and energy expenditure (EE) with energy intake (EI). Methods: Data from 93 women (BMI = 25.5 [SD 4.2] kg/m 2) recruited for two studies (Study 1, n = 48, BMI = 25.0-34.9 kg/m 2 ; Study 2, n = 45, BMI = 18.5-24.9 kg/m 2) were examined. Body composition, resting metabolic rate (RMR), and test meal EI were assessed during a laboratory probe day. Physical activity, total daily EE (TDEE), and self-reported freeliving 24-hour EI were collected during 7 days. Results: In the whole sample, fat-free mass (r = 0.45; P < 0.001), RMR (r = 0.41; P < 0.001), and TDEE (r = 0.39; P < 0.001), but not fat mass (r = 0.17; P = 0.11), were positively associated with free-living 24-hour EI. Body fat percentage moderated the associations of RMR (β = −1.88; P = 0.02) and TDEE (β = −1.91; P = 0.03) with mean free-living 24-hour EI. Fat mass was negatively associated with test meal EI only in the leaner group (r = −0.43; P = 0.004), and a weak nonlinear association was observed in the whole sample (r 2 = 0.092; P = 0.04). Conclusions: Body fat percentage appears to moderate the associations between EE and daily EI. Furthermore, the negative association between fat mass and test meal EI observed in leaner individuals was absent in those with higher body fatness. Therefore, higher levels of body fatness may weaken the coupling between EE and EI.

The importance of fat-free mass and constituent tissue-organs in the control of human appetite

“…For example, Grannell et al [10] found a positive association between FFM and ad libitum test meal energy intake in 43 individuals with severe obesity, but the strength of this association was weaker in those with a higher BMI. These findings are supported by Casanova et al [9], who reported that percentage body fat moderated the associations between RMR and total daily energy expenditure with free-living 24-h energy intake. Weaker associations in those with obesity are in line with the notion of leptin resistance [11], and suggests that the relationship between fat mass and energy intake is more variable than with FFM and may be differ depending on the level of adiposity.…”

“…The findings of McNeil et al [6] that leptin was negatively associated with energy intake are interesting in that previous studies have reported inconsistent findings between fat mass and energy intake, with negative associations reported in lean individuals but no association or weak positive associations seen in those with obesity (see Blundell et al [5]). To examine this issue further, Casanova et al [9] recently investigated the associations between body composition, energy expenditure and energy intake ( ad libitum test meal and free-living 24-h energy intake) in healthy weight ( n = 45) and individuals with overweight or obesity ( n = 48). Fat mass was negatively associated with test meal energy intake in the lean individuals, but no associations were seen in those with overweight or obesity.…”

Fat-free mass and resting metabolic rate are determinants of energy intake: implications for a theory of appetite control

“…As noted by the authors these 'findings suggest that at the extremes of obesity FFM continues to promote hunger and EI' [50, p. 1], but the strength of this association was weaker in individuals with a higher BMI. These findings were supported by Casanova et al [56] who reported that percentage body fat moderated the associations between FFM and free-living 24 h EI in 45 healthy weight and 48 individuals with obesity, with these associations becoming weaker at higher percentage body fat levels. When considered alongside similar findings [54,55,57], these data suggest that excess FM may disrupt the coupling between FFM and EI.…”

Dietary Intake and Energy Expenditure in Breast Cancer Survivors: A Review

“…Specifically, the FFM-EI relationship is mediated by RMR, which positively relates to meal size and EI [79]. The correlation between RMR and EI occurs independently of FM and BMI [80], although it may be less apparent in people with obesity [81]. It is believed that EI is also driven by habitual TDEE; that is, individuals with increased physical activity and RMR would be expected to have a higher EI to compensate for their higher energy requirements.…”