The impact of COVID-19 on diet – challenges and opportunities ahead

Dr. Yvonne Finnegan Ph.D Registered Dietitian

Contributed by Dr. Yvonne Finnegan Ph.D Registered Dietitian

Since the outbreak of COVID-19 over a year ago, many surveys have attempted to capture the impact of the various restrictions and disruption to daily patterns on diet and health behaviours.

The combination of restricted daily routines, increased screen time, boredom, reduced physical activity, loss of employment and stockpiling of food has created a perfect storm, tipping the balance in favour of weight gain and poorer eating habits. However, other changes such as a reduction in the daily commute, greater community action, time to improve cooking skills and increased use of online workouts may have had a positive impact on lifestyle for others.

What is clear is that the experience has impacted individuals very differently.

The ‘Covid Stone’ or ‘Quarantine 19’

Largely anecdotal in the first wave of the pandemic and referred to in the media as the ‘Covid stone’ or ‘Quarantine 19’, data has since emerged to support the impact of COVID restrictions in promoting weight gain, but not necessarily in all individuals1. While the surveys are self-reported and therefore prone to bias and with restrictions on research due to COVID, it is likely that data from more objective measurements of weight gain in populations will be delayed.

A study of U.S. adults conducted last March/April in the initial phase of restrictions showed that 44% reported maintaining weight, 18% lost weight and 36% gained weight. Of those gaining >5 lbs (2.3kg), 33% continued to gain weight in Sept/October 2020 when restrictions had lifted, with 28% maintaining a higher body weight2. In those who gained weight, takeout meal frequency increased, stress, and low craving control continued to persist after the lockdown eased. Again, the data here is self-reported but highlights that lifting restrictions does not necessarily mean that individuals will naturally revert to healthier lifestyles and support will be needed to help people recover or prevent further weight gain. Similarly, 21% of those surveyed in 17 countries across the Middle East and North Africa reported weight gain, with the other 79% presumably maintaining or decreasing weight3.

Spending time out of school also increases the risk of weight gain in children. Pre-COVID, several U.S. studies had linked the closure of schools in the summer period to accelerated weight gain and a reduction in fitness in children4-5. COVID-19 restrictions are likely to present many of the same challenges particularly in lower socio-economic groups and increased obesity rates have already been reported6.

Masked shopper

A mixed picture on dietary behaviours

A review published in January this year has confirmed that the COVID-19 restrictions have both negatively and positively impacted dietary practices throughout Europe and globally1. Using studies mainly based on online surveys of self-reported behaviours in adults, a mixed picture emerges. Some studies report improvements in certain dietary practices including an increase in the consumption of fresh produce (mostly fruit and vegetables) and home cooking, while the majority of studies reported poorer consumption habits including increased meal frequency, alcohol consumption, late evening snacking and a reduction in the consumption of fresh produce. Within the U.S., one of two studies reported a reduction in fresh produce but limited supply and pricing rather than choice may have had a role to play. Those with a higher BMI were more likely to develop unhealthy dietary habits during quarantine1,7. On the upside, another study has confirmed an increase in inclusion of children in cooking activities during the COVID-19 pandemic8.

Much of the published research however captured the impact of the first set of restrictions and it may be another year before we can fully assess the overall impact of successive ‘lockdowns’. A recent global survey of dietary lifestyles carried out in November 2020 (covering at least two periods of high level restrictions in some countries) also reinforces this mixed response in terms of dietary and other health changes9. Overall, 22% of participants stated that the pandemic had improved their diet and food choices while 15% cited that it had worsened. Specific changes include:

  • A 30% increase in fruit and vegetables over the last 12 months and a reduction in red meat consumption
  • 32% reported consuming vitamins and minerals daily with an increased focus on immunity and general health.
  • 24% cited they now seeking out food/drink with immune boosting benefits, with greater numbers in China and the US subscribing to this versus Europe.
  • An increased association with plant-based diets (vegetarian, vegan or flexitarian) and 47% reporting that ethically and sustainably sourced ingredients are more important to them than before the pandemic.
  • Overall however, more people reported that their weight, fitness, body image, mental health and energy levels had worsened rather than improved.
Masked shoppers browsing shelves

Dietary surveys are usually the cornerstone on which nutritionists assess changes in dietary behaviour, but this type of data tends to lag behind due to the more intensive analysis required. Going forward it will be interesting to see how well the self-reported dietary changes align with actual dietary assessments during this period but it is clear that COVID-19 restrictions have had a negative impact on the diet of some individuals.

Navigating the way ahead

As we count down to the resumption of some level of normality, we face some significant challenges ahead. It is inevitable that there will be a certain amount of making up for ‘lost time’, including an element of over-consumption which may exacerbate issues like weight gain. However, prior to the COVID pandemic we were already in the midst of a global obesity epidemic, with national authorities and health/nutrition communities using multiple strategies to address it. These strategies have not changed but may need some adjustments as some degree of restrictions linger and we will need to maintain the agile and ‘can do’ attitude that emerged during COVID.

The disproportionate impact of COVID on those who are obese has focused efforts on this chronic condition and support will be necessary to help people to reset or adopt healthier lifestyles. Some government authorities have redoubled efforts in this area with an updated range of proposed measures including reformulation, education and restrictions on marketing and promotional offers on high fat and sugar foods10. Due to overburdened healthcare systems, key stakeholders like schools, communities and families may need to be supported to step in more to help. Strategies identified to prevent continued weight gain in children include increasing access to structured summer programmes for at risk groups11 and greater consumption of fruit and vegetables, identified as a priority by WHO12.

For the food industry, reformulation remains an important part of the toolbox for addressing obesity and is a useful one as it requires little action on the part of the consumer. With advances in fibres, sugars and fat can be replaced with dietary fibre, reducing energy density. Increasing fibre this way can also help close the current gap in fibre intakes observed in most developed countries13,14. While this is certainly not a silver bullet for obesity, the more products that can be successfully reformulated to lower energy density, the greater the potential impact on day-to-day energy and fibre intakes.

However, we cannot lose sight of the opportunity presented in the last year to play out what effect more seismic social changes might have on our health behaviours. To what extent has a reduction in the daily commute driven other positive behaviours like increased time for exercise, cooking from scratch, eating meals together as a family? Can we encourage continued use of online workouts or community-based meal delivery/shopping schemes that provided nutritious food to the vulnerable? Can ‘telemedicine’, so widely adopted during the pandemic, improve access to healthcare advice? We also have a unique opportunity to learn how the way we lived in the last year may have facilitated better dietary and health behaviours so that we can truly ‘build back better’.


1. Bennett G, Young E, Butler I, Coe S. The Impact of Lockdown During the COVID-19 Outbreak on Dietary Habits in Various Population Groups: A Scoping Review. Front Nutr. 2021 Mar 4;8:626432. doi: 10.3389/fnut.2021.626432. PMID: 33748175; PMCID: PMC7969646.
2. Bhutani S, vanDellen MR, Cooper JA. Longitudinal Weight Gain and Related Risk Behaviors during the COVID-19 Pandemic in Adults in the US. Nutrients. 2021 Feb 19;13(2):671. doi: 10.3390/nu13020671. PMID: 33669622; PMCID: PMC7922943
3. Abouzid M, El-Sherif DM, Eltewacy NK, Dahman NBH, Okasha SA, Ghozy S, Islam SMS; EARG Collaborators. Influence of COVID-19 on lifestyle behaviors in the Middle East and North Africa Region: a survey of 5896 individuals. J Transl Med. 2021 Mar 30;19(1):129. doi: 10.1186/s12967-021-02767-9. PMID: 33785043; PMCID: PMC8008335.
4. Moreno JP, Johnston CA, Woehler D. Changes in weight over the school year and summer vacation: results of a 5-year longitudinal study. J Sch Health. 2013 Jul;83(7):473-7. doi: 10.1111/josh.12054. PMID: 23782089.
5. Lane TS, Sonderegger DL, Holeva-Eklund WM, Brazendale K, Behrens TK, Howdeshell H, Walka S, Cook JR, de Heer HD. Seasonal Variability in Weight Gain Among American Indian, Black, White, and Hispanic Children: A 3.5-Year Study. Am J Prev Med. 2021 May;60(5):658-665. doi: 10.1016/j.amepre.2020.12.010. Epub 2021 Feb 23. PMID: 33632651; PMCID: PMC8068602.
6. Jenssen BP, Kelly MK, Powell M, et al. COVID-19 and Changes in Child Obesity. Pediatrics. 2021;147(5):e2021050123
7. Robinson E, Boyland E, Chisholm A, Harrold J, Maloney NG, Marty L, Mead BR, Noonan R, Hardman CA. Obesity, eating behavior and physical activity during COVID-19 lockdown: A study of UK adults. Appetite. 2021 Jan 1;156:104853. doi: 10.1016/j.appet.2020.104853. Epub 2020 Oct 7. PMID: 33038479; PMCID: PMC7540284
8. Benson, T., Murphy, B., McCloat, A., Mooney, E., Dean, M., & Lavelle, F. (2021). From the pandemic to the pan: The impact of COVID19 on parental inclusion of children in cooking activities - a cross-continental survey. Public health nutrition, 1–17. Advance online publication.
9. BordBia study conducted via N=2,000+ online interviews in 9 key markets (Ireland, UK, Germany, Sweden, US, Italy, France, The Netherlands and China). Final sample size achieved for this project was: N=18,591. Fieldwork was conducted in November 2020. Research is nationally representative of adults in each market.
10. Department of Health and Social care. Policy paper. Tackling obesity: empowering adults and children to live healthier lives. Published 27 July 2020
11. Weaver RG, Beets MW, Brazendale K, Brusseau TA. Summer Weight Gain and Fitness Loss: Causes and Potential Solutions. Am J Lifestyle Med. 2018 Jan 12;13(2):116-128. doi: 10.1177/1559827617750576. PMID: 30800015; PMCID: PMC6378497.
12. Williams J, et al. A Snapshot of European Children's Eating Habits: Results from the Fourth Round of the WHO European Childhood Obesity Surveillance Initiative (COSI). Nutrients. 2020 Aug 17;12(8):2481. doi: 10.3390/nu12082481. PMID: 32824588; PMCID: PMC7468747.
13. Rippin HL, Hutchinson J, Jewell J, Breda JJ, Cade JE. Adult Nutrient Intakes from Current National Dietary Surveys of European Populations. Nutrients. 2017 Nov 27;9(12):1288. doi: 10.3390/nu9121288. PMID: 29186935; PMCID: PMC5748739.
14. McGill CR, Fulgoni VL 3rd, Devareddy L. Ten-year trends in fiber and whole grain intakes and food sources for the United States population: National Health and Nutrition Examination Survey 2001-2010. Nutrients. 2015 Feb 9;7(2):1119-30. doi: 10.3390/nu7021119. PMID: 256 Yu D, Zhao L, Zhao W. Status and trends in consumption of grains and dietary fiber among Chinese adults (1982-2015). Nutr Rev. 2020 Aug 1;78(Suppl 1):43-53. doi: 10.1093/nutrit/nuz075. PMID: 32728754. 71414; PMCID: PMC4344579.

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