The impact of COVID-19 has been far reaching. Alongside the devastating humanitarian cost of the pandemic, nations have collectively taken significant economic hits due to the loss of business and the limitations imposed on international borders. Alongside this, it’s also important to consider how the lives of individuals around the world have been significantly altered by lockdown measures, remote work and isolation. 

Evidence suggests that the pandemic has affected our mental health, physical activity, sleep patterns, dietary habits and physical health in a variety of ways. Let’s explore some key findings into the impact of COVID-19, and subsequent lockdown measures, have had on our lifestyles. 

Sleep and Physical Activity

The disruptive nature of COVID-19 has been documented in a recent study published in the Proceedings of the National Academy of Sciences of the United States of America, in which a longitudinal dataset of college students before and after the pandemic showed significant changes in the physical activity, sleep, time use, and mental health of participants ¹. 

Fig 1. Here, we can see a visualisation of the study’s findings for participants, with the spring of 2020 represented in red, and the spring of 2019 in blue. The gray shading shows 95% confidence intervals for the weighted curves drawn out. 

As the visualisation shows, steps logged in 2019 were fairly consistent within the sample, with an average of between 10,300 and 10,400 steps taken throughout terms. This trend continues throughout February 2020 (as seen in Fig 1A), before falling to an average of 4,600 daily steps - representing a decline of more than 50%. 

We can see an extremely similar trend occurring in terms of physical activity, as seen in Fig 1B. For reference, physical activity is measured as minutes in which an individual is nonsedentary for at least 10 minutes. Results show that nonsendary minutes fell by around 90 minutes on average from 4.4 hours per day to 2.9 hours per day among students. 

Perhaps most interesting is the disruptions to sleep occurring for students. As trends within Figs 1C and 1D appear to show, sleep duration among participating students appears to be driven by progressively later wake up times. Significantly, studies indicate that misalignment of sleep patterns with natural circadian rhythms can lead to increased instances of depression in individuals ².

During the height of the pandemic, NeurologyToday coined the phrase ‘COVID-smonia’ as more neurologists reported patients suffering from disrupted sleep patterns owing to fears surrounding the virus ³. 

The notion of disrupted sleep during a time when the morning commute had largely been eradicated for non-essential workers may seem somewhat counterintuitive. After all, logically workers will have more time to spend in bed. However, a 2017 study from the UN International Labour Organization found that as much as 42% of remote workers claim to ‘wake repeatedly in the night’ - indicating a continuation of the trend in the wake of the pandemic ⁴.

Dietary Alterations

In an Italian questionnaire-based study intending to document the impact that the virus has had on the diets of individuals aged 12 years of age and over, it became clear that the pandemic and subsequent lockdowns carried a profound impact on the food that participants would consume ⁵.

Fig 2. Here we can see the diagram showing the variations in food intake among survey participants in Italy aged 12 and over. Interestingly, 37.4% of participants claimed to have attained a healthier diet in the wake of lockdown, while 35.8% stated that their diet had become less healthy. 

Individuals who decreased their junk food consumption (29.8%) were notably more representative than those who increased it at 25.6%. The study found that binary logistic regression analysis showed that a higher BMI and lower age resulted in increases in junk food consumption - as well as an enhanced appetite and after dinner hunger. These findings were corroborated by another study based on food consumption and behaviour in Qatar during the pandemic, where over 50% of respondents either never ordered fast food or had food delivered much less during the pandemic ⁶. 

Fig 2 shows that Italy largely indulged in more homemade foods during lockdown, while the consumption of hot beverages also increased significantly. These findings correspond with survey results published in Sprudge, which showed that while fewer individuals were consuming 1-2 cups of coffee on a daily basis, the consumption of three or more cups has risen ⁷. The survey showed that, on average, the daily consumption of caffeine rose by 13% in lockdown from 2.45 cups per day to 2.77 cups per day - indicating another possible source of sleep disruption as a result of changing lifestyles during the pandemic ⁸.

Blue-Light Exposure

Worryingly, the impact of COVID-19 and the lockdowns the pandemic has enforced may also be causing long-term damage to our bodies. One study published in the National Library of Medicine highlights that the increased exposure individuals have had to device screens like smartphones, laptops and TVs during the pandemic may be leading to the emission of blue light at variable wavelengths in which variable durations of exposure could cause oxidative damage to skin cells ⁹.

According to an article published in the Independent in spring 2020, some smartphone users had reported that their screen time had increased by as much as 200% during the early stages of lockdown ¹⁰.

Research indicates that increased exposure to blue light emitted from smartphones and other device screens can significantly hinder our ability to get a good night’s sleep, and it can also damage our eyesight ^{11 12}. 

Due to problems related to screen time, it’s estimated that by 2050, over half of the global population will need glasses ¹³. According to a recent BBC article, this trend may accelerate in the wake of the pandemic, with 38% of people surveyed from a sample size of 2,000 believing their eyesight has worsened since the emergence of COVID-19 ¹⁴.

More than a year on from the first instances of lockdown across the world, we’re still only beginning to understand the severe lifestyle impact the pandemic has had on global populations. With the long-term lifestyle implications for populations still to be monitored, the coming transition into the age of the ‘new normal’ as the world begins to shift away from the pandemic will be of paramount interest. Will the observational changes that have been taking place during lockdown continue to embed themselves into society? Or will we witness a reversion to pre-pandemic norms? Time will tell.

References

¹ Giuntella et al (2021) "Lifestyle and mental health disruptions during COVID-19 | PNAS." 2 Mar. 2021, https://www.pnas.org/content/118/9/e2016632118. Accessed 17 May. 2021.

² Germain & Kupfer (2008) "CIRCADIAN RHYTHM DISTURBANCES IN DEPRESSION." https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2612129/. Accessed 17 May. 2021.

³ "Sleep Neurologists Call It 'COVID-Somnia'—Increased Sleep Di ...." 9 Jul. 2020, https://journals.lww.com/neurotodayonline/fulltext/2020/07090/sleep_neurologists_call_it.1.aspx. Accessed 17 May. 2021.

⁴ "Working anytime, anywhere: The effects on the world of work ...." 15 Feb. 2017, https://www.eurofound.europa.eu/publications/report/2017/working-anytime-anywhere-the-effects-on-the-world-of-work. Accessed 17 May. 2021.

⁵ Renzo et al (2020) "Eating habits and lifestyle changes during COVID-19 lockdown: an ...." 8 Jun. 2020, https://translational-medicine.biomedcentral.com/articles/10.1186/s12967-020-02399-5. Accessed 17 May. 2021.

⁶ "Sustainability | Free Full-Text | Impact of COVID-19 on Food ... - MDPI." https://www.mdpi.com/2071-1050/12/17/6973. Accessed 17 May. 2021.

⁷ "Survey Results: How Has Coffee Consumption Been Impacted By ...." 16 Apr. 2020, https://sprudge.com/survey-results-how-has-coffee-consumption-been-impacted-by-covid-19-162838.html. Accessed 17 May. 2021.

⁸ Drake et al (2013) "Caffeine Effects on Sleep Taken 0, 3, or 6 Hours before ... - NCBI - NIH." https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3805807/. Accessed 17 May. 2021.

⁹ Jakhar et al (2020) "Increased usage of smartphones during COVID-19: Is that ... - PubMed." https://pubmed.ncbi.nlm.nih.gov/33460228/. Accessed 17 May. 2021.

¹⁰ "Coronavirus: Phone users shocked by how much their screentime ...." 30 Mar. 2020, https://www.independent.co.uk/life-style/gadgets-and-tech/news/coronavirus-screen-time-phone-use-iphone-a9433251.html. Accessed 17 May. 2021.

¹¹ "Blue light has a dark side - Harvard Health." 7 Jul. 2020, https://www.health.harvard.edu/staying-healthy/blue-light-has-a-dark-side. Accessed 17 May. 2021.

¹² "How Does Blue Light Affect You? - WebMD." 3 Oct. 2020, https://www.webmd.com/eye-health/blue-light-health. Accessed 17 May. 2021.

¹³ "39 Glasses Statistics - - Vision Magazine - Eyeglasses.com." https://blog.eyeglasses.com/vision-magazine/glasses-statistics/. Accessed 17 May. 2021.

¹⁴ "Covid: Eyesight risk warning from lockdown screen time - BBC News." 12 Jan. 2021, https://www.bbc.com/news/health-55620100. Accessed 17 May. 2021.