@Article{info:doi/10.2196/25529,
author="Vuorinen, Anna-Leena
and Helander, Elina
and Pietil{\"a}, Julia
and Korhonen, Ilkka",
title="Frequency of Self-Weighing and Weight Change: Cohort Study With 10,000 Smart Scale Users",
journal="J Med Internet Res",
year="2021",
month="Jun",
day="28",
volume="23",
number="6",
pages="e25529",
keywords="self-monitoring; self-weighing; weight change, weight loss, normal weight, overweight, obese, temporal weight change",
abstract="Background: Frequent self-weighing is associated with successful weight loss and weight maintenance during and after weight loss interventions. Less is known about self-weighing behaviors and associated weight change in free-living settings. Objective: This study aimed to investigate the association between the frequency of self-weighing and changes in body weight in a large international cohort of smart scale users. Methods: This was an observational cohort study with 10,000 randomly selected smart scale users who had used the scale for at least 1 year. Longitudinal weight measurement data were analyzed. The association between the frequency of self-weighing and weight change over the follow-up was investigated among normal weight, overweight, and obese users using Pearson's correlation coefficient and linear models. The association between the frequency of self-weighing and temporal weight change was analyzed using linear mixed effects models. Results: The eligible sample consisted of 9768 participants (6515/9768, 66.7{\%} men; mean age 41.5 years; mean BMI 26.8 kg/m2). Of the participants, 4003 (4003/9768, 41.0{\%}), 3748 (3748/9768, 38.4{\%}), and 2017 (2017/9768, 20.6{\%}) were normal weight, overweight, and obese, respectively. During the mean follow-up time of 1085 days, the mean weight change was --0.59 kg, and the mean percentage of days with a self-weigh was 39.98{\%}, which equals 2.8 self-weighs per week. The percentage of self-weighing days correlated inversely with weight change, r=--0.111 (P<.001). Among normal weight, overweight, and obese individuals, the correlations were r=--0.100 (P<.001), r=--0.125 (P<.001), and r=--0.148 (P<.001), respectively. Of all participants, 72.5{\%} (7085/9768) had at least one period of ≥30 days without weight measurements. During the break, weight increased, and weight gains were more pronounced among overweight and obese individuals: 0.58 kg in the normal weight group, 0.93 kg in the overweight group, and 1.37 kg in the obese group (P<.001). Conclusions: Frequent self-weighing was associated with favorable weight loss outcomes also in an uncontrolled, free-living setting, regardless of specific weight loss interventions. The beneficial associations of regular self-weighing were more pronounced for overweight or obese individuals. ",
issn="1438-8871",
doi="10.2196/25529",
url="https://www.jmir.org/2021/6/e25529",
url="https://doi.org/10.2196/25529",
url="http://www.ncbi.nlm.nih.gov/pubmed/34075879"
}