A Cochrane review found that people consistently ate more food or drank more non-alcoholic beverages when offered larger portions, packages, or tableware.
The number at a glance
Change the size, and the same food feels different.
The modeled change in average daily food energy intake among UK adults if the observed effect continued across the whole diet
What the study can say
The environment matters—not only willpower.
When the amount in front of us becomes the reference point, finishing it can feel normal. The offered size may shape a decision alongside hunger.
This is not an argument that a large portion is always wrong. It is evidence that eating amount is not determined by personal intention alone.
Read the 12–16% carefully
The estimate is not a prediction for one person.
The 12–16% figure models what might happen if the review’s observed effect continued across an entire diet. It does not mean one large meal automatically adds that amount.
Most included studies were conducted in the United States and commonly measured short-term responses. The limitations belong beside the headline.
What to keep
Portion size is shaped by the visible reference point, not willpower alone.
How MorselFlow fits
You can correct the estimated portion before saving.
MorselFlow may suggest a small, typical, or large portion from a photo, but it does not treat the result as certain.
Because bowls and plating change how food looks, the suggestion remains editable before it enters your timeline.
The figures in this article come from population guidance or research. They are not personal diagnosis, treatment, or nutritional advice. Food, portion, and nutrition suggestions are estimates and may differ from the actual meal.