How distance and visibility affect food consumption without conscious awareness.
What the evidence says
- 2019 Cochrane review: food placed farther away reduces consumption (SMD −0.60, moderate effect)1
- Effect operates below conscious awareness — people don't realize proximity influences choices2
- Visible food generates repeated cues; hidden food doesn't trigger these prompts3
- Reducing available options also reduces selection (large effect size, SMD −1.13)1
- Effect persists over time, not just novelty2
- Specific distances tested: 20cm vs 70cm showed meaningful differences (arm's reach vs standing up)2,4
- Three distances were tested in the study that separated the mechanisms: snacks at 20cm, 70cm or 140cm (n=77), with *both* distant conditions reducing the probability and the amount of intake against the 20cm condition4
- The same work measured perceived effort and visual salience separately and found distance moved *effort but not salience* — which is what licenses the effort reading rather than a visibility reading4
- No compensatory behavior followed: greater distance did not increase craving or produce later compensation, so the intervention does not appear to backfire4
- Distance effect works through perceived effort, not reduced visual salience4
- 18 of 24 Cochrane studies examined proximity interventions1
- Cochrane-identified proximity mechanism: effort minimization — "humans tend to take the least effortful course of action without the need for conscious deliberation"1
- Equity concern: Cochrane meta-regression found larger proximity effects among low-deprivation populations — these interventions may benefit already-advantaged groups more1