• Record: found
  • Abstract: found
  • Article: found
Is Open Access

The causal role of breakfast in energy balance and health: a randomized controlled trial in lean adults1234

Read this article at

      There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.


      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/m 2 in women ( n = 21) and ≤7.5 kg/m 2 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. This trial was registered at as ISRCTN31521726.

      Related collections

      Most cited references 44

      • Record: found
      • Abstract: not found
      • Article: not found

      Executive Summary of the Third Report of the National Cholesterol Education Program (NCEP) Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults (Adult Treatment Panel III)

        • Record: found
        • Abstract: found
        • Article: found
        Is Open Access

        CONSORT 2010 Statement: updated guidelines for reporting parallel group randomised trials

        The CONSORT statement is used worldwide to improve the reporting of randomised controlled trials. Kenneth Schulz and colleagues describe the latest version, CONSORT 2010, which updates the reporting guideline based on new methodological evidence and accumulating experience. To encourage dissemination of the CONSORT 2010 Statement, this article is freely accessible on and will also be published in the Lancet, Obstetrics and Gynecology, PLoS Medicine, Annals of Internal Medicine, Open Medicine, Journal of Clinical Epidemiology, BMC Medicine, and Trials.
          • Record: found
          • Abstract: found
          • Article: found
          Is Open Access

          Dual Energy X-Ray Absorptiometry Body Composition Reference Values from NHANES

          In 2008 the National Center for Health Statistics released a dual energy x-ray absorptiometry (DXA) whole body dataset from the NHANES population-based sample acquired with modern fan beam scanners in 15 counties across the United States from 1999 through 2004. The NHANES dataset was partitioned by gender and ethnicity and DXA whole body measures of %fat, fat mass/height2, lean mass/height2, appendicular lean mass/height2, %fat trunk/%fat legs ratio, trunk/limb fat mass ratio of fat, bone mineral content (BMC) and bone mineral density (BMD) were analyzed to provide reference values for subjects 8 to 85 years old. DXA reference values for adults were normalized to age; reference values for children included total and sub-total whole body results and were normalized to age, height, or lean mass. We developed an obesity classification scheme by using estabbody mass index (BMI) classification thresholds and prevalences in young adults to generate matching classification thresholds for Fat Mass Index (FMI; fat mass/height2). These reference values should be helpful in the evaluation of a variety of adult and childhood abnormalities involving fat, lean, and bone, for establishing entry criteria into clinical trials, and for other medical, research, and epidemiological uses.

            Author and article information

            [1 ]From the Departments for Health (JAB, JDR, EAC, and DT) and Biology and Biochemistry (GDH), University of Bath, Bath, United Kingdom; and the School of Life Sciences, Queen's Medical Centre, Nottingham, United Kingdom (KT).
            Author notes

            JDR and EAC contributed equally to this article.


            Supported by a grant from the Biotechnology and Biological Sciences Research Council (BB/H008322/1). This is an open access article distributed under the CC-BY license (

            [4 ]Address correspondence to JA Betts, Department for Health, University of Bath, Bath, BA2 7AY, United Kingdom. E-mail: j.betts@ .
            Am J Clin Nutr
            Am. J. Clin. Nutr
            The American Journal of Clinical Nutrition
            American Society for Nutrition
            August 2014
            4 June 2014
            4 June 2014
            : 100
            : 2
            : 539-547

            This is an open access article distributed under the CC-BY license (

            Pages: 9
            Nutritional Status, Dietary Intake, and Body Composition

            Nutrition & Dietetics


            Comment on this article