if then produce plan
This identifier was used as an evidence-review target but was never published as a canonical Brali protocol. It is retained as provenance and deliberately does not link to a public route.
Evidence Ledger · Protocol candidate · reviewed 2026-09-01
A systematic review and meta-analysis on the effectiveness of if-then plans – in a strict sense – to facilitate fruit and vegetable consumption in adults
The reviewed source can support a conservative practical protocol.
Brali decision: Protocol candidate. This page summarizes a reviewed evidence boundary; it does not reproduce the source and it does not turn one paper into a universal prescription.
What the source supports
When an adult already intends to eat more fruit or vegetables, adding one or more explicit cue-response plans is a defensible low-resource experiment: identify a recurring situation that can be noticed and link it to a concrete action under the person's control, such as preparing, packing, buying or adding the intended food. Across 12 randomized active-control comparisons, strict if-then planning produced a small average increase in self-reported fruit-and-vegetable intake. Brali should present this as a planning aid with a modest expected effect, not as a diet prescription.
What it does not establish
- If-then planning produces a large change in diet.
- The observed increase in self-reported fruit and vegetable intake has been shown to prevent disease or improve clinical health outcomes.
- A particular cue, meal, food, portion count, reminder schedule or number of if-then plans is optimal.
- If-then planning is superior to all other nutrition interventions.
- The evidence establishes effectiveness for weight loss, calorie reduction, protein intake, supplements or other dietary targets.
- The effect generalizes equally across cultures, age groups, sexes or populations not represented in the included trials.
- The review validates medical nutrition advice for people with allergies, eating disorders, metabolic disease or other conditions requiring individualized care.
- Self-reported intake in the trials is equivalent to objectively verified dietary change.
Important limitations
- All included fruit-and-vegetable intake outcomes relied on retrospective self-report, often one or two questions estimating portions per day.
- The included samples were predominantly western European, female, Caucasian and young-to-middle-aged, limiting generalizability.
- The pooled benefit was small: about 0.29 self-reported portions per day relative to active controls.
- The review's protocol was not prospectively registered; an unpublished protocol existed and the authors narrowed the planned nutrition outcome to fruit and vegetables before analysis.
- The review's strict intervention definition required judgment about whether study instructions truly linked a perceivable cue to a response.
- The evidence concerns fruit and vegetable intake specifically and cannot be extended to other nutrition outcomes.
- The meta-analysis does not establish the clinical relevance of the modest reported intake increase.
Source context
A systematic review and meta-analysis on the effectiveness of if-then plans – in a strict sense – to facilitate fruit and vegetable consumption in adults
- Source type: meta-analysis
- Design: Systematic review and random-effects meta-analysis of randomized controlled trials comparing strict if-then planning with active control conditions. Searches of MEDLINE, Embase and PsycInfo were last run April 3, 2025. Ten articles contributed 12 comparisons and 2,399 participants, with outcomes measured from 1 week to 24 months.
- Population: Adult samples from studies conducted mainly in western Europe, plus one Canadian study. Four studies recruited university students and five recruited broader adult samples such as employees or members of a health-insurance population. Across studies, participants were predominantly young-to-middle-aged, female and Caucasian.
- Exposure / intervention: Strict if-then planning that explicitly linked a perceivable situational cue with a goal-directed response relevant to increasing fruit or vegetable intake. Examples across the reviewed interventions included planning when and where to buy, prepare, pack or eat fruit and vegetables. Active controls received similar health information and encouragement without the if-then linkage.
- Outcomes: Self-reported daily fruit and vegetable intake; Pooled mean difference between if-then planning and active control at the latest reported outcome
Citation: Melum SK, Martiny-Huenger T. Int J Behav Nutr Phys Act. 2026;23:51.
DOI: 10.1186/s12966-026-01915-y
What this changes in Brali
Editorial note: Protocol-design direction: first confirm that the user already wants to increase fruit or vegetables; this is a volitional aid, not persuasion. Pick one repeatable cue and one visible response, for example: 'If I pack lunch tonight, then I will add one fruit' or 'If I serve dinner, then I will add a vegetable.' Track whether the cue and response occurred. Avoid medical or weight-loss claims and do not prescribe a fixed portion target from this source.
Use the boundary, not just the headline
When an AI agent or a person retrieves this decision, preserve both the supported claim and the unsupported or overstated claims. Dropping the boundary would turn a reviewed source into a stronger claim than Brali actually maintains.
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