The Impact of Lockdown During the COVID-19 Outbreak on Dietary Habits in Various Population Groups: A Scoping Review

Background: Since the beginning of the COVID-19 pandemic, access to fresh food has been restricted, and people are spending more time inside and have limited their physical activity. However, more time at home may have resulted in some positive habits including an increase in cooking. The aim of this review was to assess dietary changes during the first lockdown. Themes and patterns were considered and associations with other lifestyle factors were assessed. Methods: Between June and July 2020, the PubMed, Google Scholar, and Science Direct databases were searched, and results were screened for eligibility based on title, abstract, and full text. The inclusion criteria of this search included: papers published (or in pre-print) in the year 2020; studies that investigated the impact of COVID-19 lockdown on diet; papers published in English. Exclusion criteria were as follows: papers examining dietary changes in those following a structured diet based on diagnosed conditions or dietetic advice; literature, systematic, or narrative studies reviewing previous research. Researchers agreed on the study characteristics for extraction from final papers. Results: Four thousand three hundred and twenty-two studies were originally considered with 23 final full-text papers included. Four themes were identified: dietary patterns, dietary habits (favorable), dietary habits (unfavorable), and other (includes physical activity levels, weight gain). A total of 10 studies reported an increase in the number of snacks consumed, while six studies found that participants increased their meal number and frequency during quarantine. Eleven studies reported favorable changes in dietary habits with an increase in fresh produce and home cooking and reductions in comfort food and alcohol consumption. However, nine studies found a reduction in fresh produce, with a further six reporting an increase in comfort foods including sweets, fried food, snack foods, and processed foods. Two studies reported an increase in alcohol consumption. In eight studies participants reported weight gain with seven studies reporting a reduction in physical exercise. Conclusion: The effect of COVID-19 lockdown both negatively and positively impacted dietary practices throughout Europe and globally, and negative diet habits were associated with other poor lifestyle outcomes including weight gain, mental health issues, and limited physical activity. Both in the short term and if sustained in the long term, these changes may have significant impacts on the health of the population.