Purpose: The aim of this study was to investigate the change of restrictions applied in the COVID-19 pandemic in the diet behaviors, physical activities and stress levels of adults in Turkish population with this study. Materials and Methods: This study, designed as a crosssectional type, was conducted publicly with people who are 18 years old and over this age and living in different provinces of Turkey between 9-18 June 2020. Due to the measures of the pandemic process, the data were collected by electronic survey from 579. Participant Information Form, Dietary Behavior Form, International Physical Activity Questionnaire-Short Form and a four-item form of the Perceived Stress Scale were used to collect the research data. Results: Of the participants, 69.7% consumed their favorite foods more, 70.4% increased the frequency of snacking after meals, 74.8% increased tea and coffee consumption, 65.1% increased consumption of sugary foods such as chocolate and sweets, 68.9% increased flour and bakery products, and 67.9% increased the fruit consumption. 54.1% of the participants, 56.3% of the women and 48.1% of the men were inactive. Perceived stress level of women was higher and the difference was significant. Conclusion: During pandemics period, that the popular foods were consumed more, nearly half of the participants in the study and more than half of the women spent the whole day in a closed environment and more than half of the participants were inactive.