Bite count rates in free-living individuals: new insights from a portable sensor

Background: Conclusions regarding bite count rates and body mass index (BMI) in free-living populations have primarily relied on self-report. The objective of this exploratory study was to compare the relationship between BMI and bite counts measured by a portable sensor called the Bite Counter in free-living populations and participants eating in residence.

Methods: Two previously conducted studies were analyzed for relationships between BMI and sensor evaluated bite count/min, and meal duration. Participants from the first study (N = 77) wore the bite counter in a free-living environment for a continuous period of 14 days. The second study (N = 214) collected bite count/min, meal duration, and total energy intake in participants who consumed one meal in a cafeteria. Linear regression was applied to examine relationships between BMI and bite count/min.

Results: There was no significant correlation in the free-living participants average bite counts per second and BMI (R² = 0.03, p = 0.14) and a significant negative correlation in the cafeteria participants (R ² = 0.04, p = 0.03) with higher bite count rates observed in lean versus obese participants. There was a significant correlation between average meal duration and BMI in the free-living participants (R ² = 0.08, p = 0.01). Total energy intake in the cafeteria participants was also significantly correlated to meal duration (R ² = 0.31, p < 0.001).

Conclusions: With additional novel applications of the Bite Counter, insights into free-living eating behavior may provide avenues for future interventions that are sustainable for long term application.