Supporting The Many Lives of Personal Data with Rebite: LLM-Powered Goal-Directed Framing in Food Journaling
2026-08-21 • Human-Computer Interaction
Human-Computer Interaction
AI summaryⓘ
The authors explain that people’s health goals often change, but tracking systems usually don’t adjust well, causing people to restart their progress. They introduce "goal-directed framing," which lets a system reinterpret past data based on a person’s current goals instead of locking the data’s meaning at the time it was recorded. They built Rebite, a food journaling app that uses AI to read meal photos and give feedback tied to changing goals. In a study, participants found this method helped them understand and adjust their goals better by showing how old data fits new priorities. The authors also highlight design challenges and suggestions for systems that track changing goals.
personal informaticsgoal-directed framingRebitephoto-based food journalinglarge language models (LLMs)goal adaptationself-reflectiondietary goalsdata reframinguser engagement
Authors
Weijun Li, Daniel A. Epstein
Abstract
People's health and tracking goals frequently change, but most personal informatics systems struggle to adapt, leading people to abandon their data and start over. We propose goal-directed framing, an approach that repositions goals within personal informatics systems. Instead of fixing the meaning of data at capture time, the approach frames the collected data through the current goal and reframes it whenever the goal changes. We realize this in Rebite, a photo-based food journaling system that uses LLMs to read unstructured meal photos and produce goal-directed feedback. In a one-week deployment with 21 participants managing multiple dietary goals, we find that goal-directed framing shaped how participants engaged with their goals. Translating a goal into metrics helped them see what it meant in practice, confirming existing priorities, surfacing what they overlooked, and revealing where the metrics fell short. When goals changed, seeing past meals reframed under the new goal exposed overlaps and conflicts, prompting participants to negotiate trade-offs and refine priorities. We discuss how goal-directed framing both supports and complicates reflection as goals change, and offer design implications for personal informatics systems to support evolving goals.