Research paper
Rolls BJ. The relationship between dietary energy density and energy intake. Physiology & Behavior. 2009;97(5):609-615. doi:10.1016/j.physbeh.2009.03.011. PMID: 19303887. PMCID: PMC4182946.
Why we cite it
Synthesised the evidence that studies of macronutrient composition are "incomplete, or could be misleading" — the review's own words — when they do not also account for energy density (kcal/g). Directly relevant to the project because lowering energy density without changing macronutrient proportions enhanced satiety and reduced subsequent intake, in evidence spanning 26 preschool-age children and 658 adults in the PREMIER trial, where those with the largest reduction in energy density lost significantly more weight than those with a modest one. *The review reasons from the regularity that people "tend to" eat a consistent weight of food; it does not set out to demonstrate it.* That premise is the load-bearing assumption behind the whole energy-density case, and it is worth naming as an assumption wherever this record is cited.
About the author
Barbara J. Rolls is the Helen A. Guthrie Chair in Nutritional Sciences at Penn State University, where she has directed the Laboratory for the Study of Human Ingestive Behavior since 1992. Previously she held a faculty position at Johns Hopkins University School of Medicine and conducted early research at the University of Oxford. She is an internationally recognised authority on energy density and volumetrics, with over 250 scientific publications and six books including The Volumetrics Weight-Control Plan and The Ultimate Volumetrics Diet. Past president of both the Society for the Study of Ingestive Behavior and The Obesity Society, she received The Obesity Society's Presidential Medal of Distinction, an ASNS Award in Human Nutrition, and an NIH MERIT award.