Weight changes during the COVID-19 home confinement. Effects on psychosocial variables

•During the COVID-19 home confinement, most individuals declared no weight changes.•Males and obese individuals had greater weight variability.•Depressive symptoms were linked to larger weight changes.•The concept of depreobesity was expanded to include weight loss too.•Physical activity and optimism were found protective elements for weight change. The goal was to assess individuals’ weight changes and their connections with depressive symptoms, optimism and physical activity. 4379 Spanish citizens, 16–84 years, participated. Most participants declared no weight changes. Males, young and obese individuals had greater weight variability. Depressive symptoms were linked to larger weight changes. Optimism and MVPA followed a descending pattern from ≥−3 kg. MVPA minutes/week and fulfilling physical activity recommendations were inversely associated to weight changes. The COVID-19 confinement impacted individuals’ weight, expanding depreobesity to include weight loss. Optimism and physical activity seemed to be “protective elements”.