Changes in body weight in various population groups in Poland during the COVID-19 pandemic - a comparison of two cross-sectional studies.

Introduction And Objective: The disruption of daily activities caused by the COVID-19 pandemic had health consequences, especially during peak lockdown periods. The aim of the study is to assess the impact of the first year of the COVID-19 pandemic on the process of weight change among Polish adults.

Material And Methods: Two representative studies involving Polish adults aged 18-65 years were conducted, the first in June 2020 (N = 2527, from the perspective of the last 2-3 months), and the second a year later, in June 2021 (N = 2087, covering the last 12 months). Both surveys included two groups of respondents, and conducted using the CAWI method - computer-assisted web interview.

Results: In the first period of the COVID-19 pandemic, there were more individuals with obesity than a year later (18.7% vs 19.9%), and more respondents reported weight change in 2020 than in 2021 (53% vs 49.6%). In both surveys, women were more likely to report weight gain than men (p<0.001). Statistically significant factors for weight change in 2020 and 2021 were gender, age, and in 2021, education and relationship status. Multinomial logistic regression showed that BMI, age of 18-29 and 30-49, being male, and education below high school, was significant for weight gain. While for weight loss, BMI, age 18-29 and 30-49, being male, and year of study, were statistically significant.

Conclusions: The findings confirmed that body weight changed throughout the pandemic, depending on the time of the pandemic and selected socio-demographic factors.