ViFeed: Promoting Slow Eating and Food Awareness through Strategic Video Manipulation during Screen-Based Dining

Research Background and Problem

• Problem and Challenges: In modern society, people often engage in screen use during meals, leading to "zombie eating," a habit of mindless eating. This behavior disrupts the perception of hunger and satiety, potentially resulting in overeating and long-term health issues such as obesity. Although existing research advocates for "mindful eating" (e.g., focusing on the sensory attributes of food and eating slowly) as a way to improve eating behavior, traditional mindful eating methods typically require an environment free from screens, making them difficult to align with current screen usage habits.
• Significance: 88% of Americans interact with screens while eating, posing a significant challenge to the formation of healthy eating habits. If methods to enhance mindful eating in screen-use scenarios can be developed, this trend can be addressed, and potential health issues can be mitigated.
• Research Motivation and Related Work: The authors argue that screens should not necessarily be seen as obstacles to mindfulness but could potentially promote mindful habits, such as slow eating and food awareness, through content design. Previous studies have preliminarily explored the impact of video content on eating behavior but lack systematic exploration of "mindful eating" in screen-based dining contexts.

Solution

• Proposed Method: A video playback system called ViFeed was developed, which improves the mindful eating experience during screen-based dining through two core mechanisms: subtle adjustments to video playback speed and real-time mindful visual prompts.
  • Slow Eating: By subtly adjusting the video playback speed to 83% of the user's habitual speed (imperceptible to the user), chewing time is extended.
  • Food Awareness Reminders: Real-time visual prompts, such as encouraging users to focus on the sensory details of their food, are displayed in the corner of the screen.
• Innovations:
  1. Integrating the core principles of mindful eating into screen-based dining scenarios rather than completely rejecting screen use;
  2. Cleverly utilizing a camera to detect users' chewing behaviors and gaze direction, dynamically triggering mindful prompts;
  3. Combining implicit interventions (playback speed adjustments) with explicit prompts (on-screen visual cues).
• Implementation Steps:
  1. Study Design:
     • Three cascading studies: a Zoom-based simulated dining study (to validate the impact of playback speed adjustments on eating behavior), a participatory design workshop (to co-design visual prompts), and a one-week user experiment (to evaluate the real-world effectiveness of ViFeed).
  2. Technical Implementation:
     • Developed real-time chewing and gaze detection algorithms using facial keypoint motion captured by a camera, combined with response time thresholds to determine states and dynamically trigger prompts.
     • Created gradually varying video playback speed controls and contextualized prompts, such as icons and text displays, to enhance users' attention to food.

Research Outcomes

• Specific Findings:
  • Experiment 1: In the Zoom-based simulated study, compared to eating without distractions or watching videos at normal speed, adjusting playback speed significantly slowed eating rates (by 15.31%) and reduced food intake (by 9.65%), while enhancing food perception.
  • Experiment 2: The participatory design workshop identified key principles for designing "quickly noticeable visual prompts," such as "abstract representation," "balance between explicitness and non-intrusiveness," and "dynamic triggering mechanisms."
  • Experiment 3: ViFeed performed well in a one-week real-world test, consistently improving sensory awareness of food (e.g., attention to taste, smell, and appearance). Users also reported increased acceptance and engagement with the system.
• Comparison with Existing Solutions: ViFeed not only retains the entertainment value of video watching but also significantly enhances mindful eating behaviors without disrupting users' entertainment experience, in stark contrast to traditional offline mindfulness training methods.
• Experiment or Evaluation Results:
  • ViFeed significantly improved food-related perception metrics (e.g., food observation and appreciation);
  • Users gradually shifted from external interest in the system to intrinsic motivation and demonstrated higher focus and mindful habits in the final days of the trial.
• Limitations and Future Directions:
  • Limitations:
    1. The current study focuses on a single screen activity (watching videos) and does not cover other screen-related behaviors such as social media browsing;
    2. The technical implementation has certain limitations, such as the need for optimization of real-time detection algorithms to achieve higher accuracy and lower latency.
  • Future Directions:
    1. Explore broader screen scenarios, such as social media or mixed screen usage;
    2. Expand the content of visual prompts (e.g., incorporating nutrition education and emotional management tips);
    3. Design customized solutions for family dining scenarios;
    4. Investigate the long-term effects of interventions and explore the potential applications of ViFeed in improving psychological and physical health.

Through the design and validation of ViFeed, this study demonstrates that digital interventions can leverage existing behavioral habits to achieve effective mindfulness practices in modern dining contexts, providing new insights and empirical evidence for health technology innovation and digital mindfulness.