The causal role of breakfast in energy balance and health: a randomized controlled trial in lean adults

Background: Popular beliefs that breakfast is the most important meal of the day are grounded in cross-sectional observations that link breakfast to health, the causal nature of which remains to be explored under real-life conditions. Objective: The aim was to conduct a randomized controlled trial...

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Main Authors: Betts, James A., Richardson, Judith D., Chowdhury, Enhad A., Holman, Geoffrey D., Tsintzas, Kostas, Thompson, Dylan
Format: Article
Published: American Society for Nutrition 2014
Online Access:https://eprints.nottingham.ac.uk/44967/
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author Betts, James A.
Richardson, Judith D.
Chowdhury, Enhad A.
Holman, Geoffrey D.
Tsintzas, Kostas
Thompson, Dylan
author_facet Betts, James A.
Richardson, Judith D.
Chowdhury, Enhad A.
Holman, Geoffrey D.
Tsintzas, Kostas
Thompson, Dylan
author_sort Betts, James A.
building Nottingham Research Data Repository
collection Online Access
description Background: Popular beliefs that breakfast is the most important meal of the day are grounded in cross-sectional observations that link breakfast to health, the causal nature of which remains to be explored under real-life conditions. Objective: The aim was to conduct a randomized controlled trial examining causal links between breakfast habits and all components of energy balance in free-living humans. Design: The Bath Breakfast Project is a randomized controlled trial with repeated-measures at baseline and follow-up in a cohort in southwest England aged 21–60 y with dual-energy X-ray absorptiometry–derived fat mass indexes #11 kg/m2 in women (n = 21) and #7.5 kg/m2 in men (n = 12). Components of energy balance (resting metabolic rate, physical activity thermogenesis, energy intake) and 24-h glycemic responses were measured under free-living conditions with random allocation to daily breakfast ($700 kcal before 1100) or extended fasting (0 kcal until 1200) for 6 wk, with baseline and follow-up measures of health markers (eg, hematology/biopsies). Results: Contrary to popular belief, there was no metabolic adaptation to breakfast (eg, resting metabolic rate stable within 11 kcal/d), with limited subsequent suppression of appetite (energy intake remained 539 kcal/d greater than after fasting; 95% CI: 157, 920 kcal/d). Rather, physical activity thermogenesis was markedly higher with breakfast than with fasting (442 kcal/d; 95% CI: 34, 851 kcal/d). Body mass and adiposity did not differ between treatments at baseline or follow-up and neither did adipose tissue glucose uptake or systemic indexes of cardiovascular health. Continuously measured glycemia was more variable during the afternoon and evening with fasting than with breakfast by the final week of the intervention (CV: 3.9%; 95% CI: 0.1%, 7.8%). Conclusions: Daily breakfast is causally linked to higher physical activity thermogenesis in lean adults, with greater overall dietary energy intake but no change in resting metabolism. Cardiovascular health indexes were unaffected by either of the treatments, but breakfast maintained more stable afternoon and evening glycemia than did fasting.
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spelling nottingham-449672020-05-04T16:49:57Z https://eprints.nottingham.ac.uk/44967/ The causal role of breakfast in energy balance and health: a randomized controlled trial in lean adults Betts, James A. Richardson, Judith D. Chowdhury, Enhad A. Holman, Geoffrey D. Tsintzas, Kostas Thompson, Dylan Background: Popular beliefs that breakfast is the most important meal of the day are grounded in cross-sectional observations that link breakfast to health, the causal nature of which remains to be explored under real-life conditions. Objective: The aim was to conduct a randomized controlled trial examining causal links between breakfast habits and all components of energy balance in free-living humans. Design: The Bath Breakfast Project is a randomized controlled trial with repeated-measures at baseline and follow-up in a cohort in southwest England aged 21–60 y with dual-energy X-ray absorptiometry–derived fat mass indexes #11 kg/m2 in women (n = 21) and #7.5 kg/m2 in men (n = 12). Components of energy balance (resting metabolic rate, physical activity thermogenesis, energy intake) and 24-h glycemic responses were measured under free-living conditions with random allocation to daily breakfast ($700 kcal before 1100) or extended fasting (0 kcal until 1200) for 6 wk, with baseline and follow-up measures of health markers (eg, hematology/biopsies). Results: Contrary to popular belief, there was no metabolic adaptation to breakfast (eg, resting metabolic rate stable within 11 kcal/d), with limited subsequent suppression of appetite (energy intake remained 539 kcal/d greater than after fasting; 95% CI: 157, 920 kcal/d). Rather, physical activity thermogenesis was markedly higher with breakfast than with fasting (442 kcal/d; 95% CI: 34, 851 kcal/d). Body mass and adiposity did not differ between treatments at baseline or follow-up and neither did adipose tissue glucose uptake or systemic indexes of cardiovascular health. Continuously measured glycemia was more variable during the afternoon and evening with fasting than with breakfast by the final week of the intervention (CV: 3.9%; 95% CI: 0.1%, 7.8%). Conclusions: Daily breakfast is causally linked to higher physical activity thermogenesis in lean adults, with greater overall dietary energy intake but no change in resting metabolism. Cardiovascular health indexes were unaffected by either of the treatments, but breakfast maintained more stable afternoon and evening glycemia than did fasting. American Society for Nutrition 2014-08-01 Article PeerReviewed Betts, James A., Richardson, Judith D., Chowdhury, Enhad A., Holman, Geoffrey D., Tsintzas, Kostas and Thompson, Dylan (2014) The causal role of breakfast in energy balance and health: a randomized controlled trial in lean adults. American Journal of Clinical Nutrition, 100 (2). pp. 539-547. ISSN 0002-9165 http://ajcn.nutrition.org/content/100/2/539 doi:10.3945/ajcn.114.083402 doi:10.3945/ajcn.114.083402
spellingShingle Betts, James A.
Richardson, Judith D.
Chowdhury, Enhad A.
Holman, Geoffrey D.
Tsintzas, Kostas
Thompson, Dylan
The causal role of breakfast in energy balance and health: a randomized controlled trial in lean adults
title The causal role of breakfast in energy balance and health: a randomized controlled trial in lean adults
title_full The causal role of breakfast in energy balance and health: a randomized controlled trial in lean adults
title_fullStr The causal role of breakfast in energy balance and health: a randomized controlled trial in lean adults
title_full_unstemmed The causal role of breakfast in energy balance and health: a randomized controlled trial in lean adults
title_short The causal role of breakfast in energy balance and health: a randomized controlled trial in lean adults
title_sort causal role of breakfast in energy balance and health: a randomized controlled trial in lean adults
url https://eprints.nottingham.ac.uk/44967/
https://eprints.nottingham.ac.uk/44967/
https://eprints.nottingham.ac.uk/44967/