Food insecurity, hoarding behavior, and environmental harshness do not predict weight changes during the COVID-19 pandemic

The COVID-19 pandemic not only presents a medical and psychological stressor to many, but has also
led to alterations that many perceived as threatening, such as reduced financial income and job
insecurity. A symptom of collective worrying were so-called panic- or ‘hamster’ purchases, whereby people
hoarded food following the introduction of governmental restrictions in response to the pandemic. This
behavior indicated subjective ‘food insecurity’ in many individuals at a time when loss of income could
potentially lead to real food insecurity for some. Since both perceived and actual food insecurity, as well
as stress, are thought to facilitate weight gain as an adaptive response, this study aimed to investigate
body weight during the pandemic. Specifically, we modeled the effects of both psychological and
environmental factors such as food insecurity, hoarding behavior and loss of income, on body on weight
as lockdown measures were introduced and loosened in four European countries. While we observe no
systematic changes in body weight over the observed period, there was inter-individual variation in
weight changes. However, contrary to our hypothesis, results show that neither food insecurity, hamster
purchases, nor loss of income were predictors of weight change or weight/height ratio in our models, and
none of our machine learning models outperformed a trivial predictor using the mean of all values for
each prediction. In conclusion, this study does not add support for the notion that perceived food
insecurity can predict weight gain or a higher weight/height ratio at a time of environmental
uncertainties. This suggests that acute alterations in appetite reported upon triggering environmental
harshness have no effect beyond that moment. Possibly life-history strategies acquired earlier in life
remained stable during this crisis with respect to food consumption and weight.