Gareth Hollands
Gareth J. Hollands is the first author of the 2015 Cochrane review of portion, package and tableware size. A Cochrane review is a systematic review produced to a fixed international methodological standard, and this one pooled sixty-one studies and 6,711 participants. It found that people consistently consume more when they are given larger portions or larger packages. The effect was small to moderate, and the evidence was rated moderate in quality, downgraded because of incomplete reporting in the underlying studies.
Who they are
Hollands is a behavioural scientist working on choice architecture, which means changing the environment people choose in rather than trying to change their minds. The portion-size review is the strongest evidence in that tradition on food, and it is unusual in covering food, alcohol and tobacco together rather than one at a time.
The review is also the reason two claims that sound alike have to be kept apart. Portion and package size is established. Tableware size, which is to say the plate-and-bowl claim, is not, and Eric Robinson's work is the reason it is not.
Key papers
Hollands, G. J., Shemilt, I., Marteau, T. M., Jebb, S. A., Lewis, H. B., Wei, Y., Higgins, J. P. T., & Ogilvie, D. (2015). "Portion, package or tableware size for changing selection and consumption of food, alcohol and tobacco", Cochrane Database of Systematic Reviews. First author. Sixty-one studies, 6,711 participants. Small-to-moderate effect, moderate-quality evidence, downgraded for incomplete reporting. Abstract and reported figures read.
Key ideas
One figure in the review needs care. Its estimate of what removing larger portions might do to daily energy intake is a modelled projection, worked out from the pooled effect rather than measured in anybody. It should never be quoted as a measured result, and it is not quoted here.
What the review does establish is simple and easy to underrate: give people more, and they take more. It holds across food, drink and cigarettes, which suggests something about how servings are read rather than anything about a particular appetite.
Portion size and plate size are separate claims with separate evidence. Running them together lets a well-supported finding smuggle in a poorly supported one.
The practical implication belongs to the environment rather than to willpower. The size of what you are handed does part of the deciding before you start.
Concepts on this site
Sources
- Hollands, G. J., et al. (2015). Cochrane Database of Systematic Reviews.
- Vault note, 2026-09-11.