Change in eating habits after 2 years of pandemic restrictions among adolescents living in a city in northern Italy: results of the COALESCENT Observational Study (Change amOng ItAlian adoLESCENTs)

Introduction

During the COVID-19 pandemic avoiding close contacts was one of the first recommendations that the WHO identified as crucial to limit human-to-human transmission, to slow down the spread of the SARS CoV-2.1 2 Italy was also the first, among Western countries, to enforce strict national restrictions.3 Initially, lockdown was limited to the Lombardy region, but few days later the restrictions became national.4 5 During the following 2 years, Brescia and Bergamo districts, both in Lombardy region, in Northern Italy, remained the two cities with the highest alert level and with the strictest isolation measures. Concerns grew about their economic and social costs of these measures. It is well known that social relationships are an important determinant of health, alongside education, lifestyle, environment, employment and working conditions.6

Adolescents are particularly at risk, given that this period of development is pivotal for psychological and biological changes and can be decisive in setting individual behavioural trajectories which influence adulthood.3 6–8 According to a recent review by Mignogna et al, during the first pandemic wave, dietary changes in children/adolescents were heterogeneous, noting that there was an increase in the consumption of unhealthy food together with an improvement in the consumption of fresh fruits, nuts and legumes.9 According to this review, a general improvement in diet quality was observed in Europe, especially in Mediterranean countries.

When focusing on the influence of restriction policies on physical activity and mental health, data are less conflicting. The results of the meta-analysis by Neville et al showed that during the COVID-19 pandemic there was a significant reduction in physical activity among children and adolescents.10 At the same time, an increase in psychological distress, especially during the early stages of the pandemic, and a high prevalence of COVID-19 related fear were noted among children and adolescents.11 12 Several authors explored changes in physical activity, mental health, sleep quality and eating behaviour, but most of the studies were cross sectional and reported data, even among people aged 12–20 years or 15–20 years, but strictly limited to the more rigid periods of restrictions, at the beginning of the pandemic and mainly among athletes.13 14 During the last year, some authors explored the impact of lifestyle changes in the long term, with particular focus on specific population categories. The study by Taheri et al was conducted among a large cohort of elite and subelites athletes, from 14 different countries, and assessed the long-term consequences of confinement measures, after 2 years from the beginning of the pandemic. The study compared mental health and nutritional practices between the two groups of athletes, in order to develop efficient strategies to prevent mental and eating disorders among athletes, in possible next similar scenarios.15

In summary, most of these surveys were limited to assessing change during the lockdown period or to explore long-term consequences but mainly among athletes, without exploring the impact of these changes in the long run in less selected populations.

To assess the extent of long-term changes in several aspects of lifestyle, with a focus on eating habits, we designed a web-based survey addressed to adolescents, 2 years after the COVID-19 pandemic, during a period of slow ‘return to normal’. The main issue we addressed was whether the lifestyle changes previously documented during the lockdown period were transient or permanent among adolescents. Investigating these aspects among adolescents can contribute to address public health actions to prevent the development of non-communicable diseases during adulthood.

Methods

Results

Out of 57 schools, 8 agreed to participate in the study, 4 state and 4 state-authorised private schools, totalling 4866 students. Among them, 1686 students returned the online questionnaire (34.6% response rate). Table 1 shows the main sociodemographic characteristics of the student sample.

Changes in eating habits compared with the pre-pandemic period

Thirty-eight per cent of our sample, reported no change in eating behaviour, 26% reported improvement, 12% reported worsening and 26% reported a change, but without a clear opinion on its quality (figure 1A). About 63% reported no change in meal planning during the day and 17% an increase in snacking; overall, 26%, 23% and 34% perceived an increase, a decrease and no change, respectively, in the total amount of food consumed during the pandemic period (figure 1B). As shown in the figure 1C, there was an increase in the regular intake of snacks and a doubling of irregularity in meal planning. About 18% of the students reported being involved in meal preparation, as compared with 8% before the pandemic.

Figure 1

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Comparison before and during the pandemic period of: panel (A) eating behaviour; panel (B) food quantity consumption; panel (C) meal planning; panel (D) ultraprocessed food consumption.

Changes in food and beverage intake, compared with the pre-pandemic period

Most of the sample reported no change in the consumption of individual foods; among the students who reported changes in the intake of individual foods, we reported the main changes in figure 2. For all healthy foods, the rate of students who reported an increase in consumption, compared with those who reported a decrease, was higher. Concerning unhealthy foods, the rate of students reporting an increase in consumption, compared with those reporting a decrease, was higher for four foods, out of the nine considered. Focusing on the intake of ultraprocessed foods (UPFs), 45.6% of the sample reported daily intake before the pandemic, increasing to 48.1% during the pandemic. In particular, students consuming UPFs three times per day or more increased from 16.2% to 22.7% (figure 1D).

Figure 2

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Change in consumption of single foods among students reporting a variation, compared with the period before the pandemic. Panel (A) change in the consumption of healthy foods; panel (B) change in the consumption of unhealthy foods. The foods selected are the same as for the calculation of the Eating Habit Index. Numbers in line refer to the rates of students reporting a positive (at the right of zero) or a negative (at the left of zero) change in the consumption of the item reported in the column.

Other relevant aspects of lifestyle

Before the pandemic, students who engaged in at least 60 min of light, moderate or intense physical activity per day were 33.6%, 30.42% and 25.7% of the sample, respectively. The level of light, moderate and intense physical activity remained the same or even increased in 79.3%, 80.6% and 81.2% of the sample, respectively, compared with the pre-pandemic period (figure 3, panels A and B). Overall, combining the answers, 30% of adolescents resulted active based on WHO recommendations. Active students had a better EHI score compared with inactive students (30% vs 23%, p=0.004).

Figure 3

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Comparison before and during the pandemic period of: panels (A) and (B), physical activity level; panel (C) sleep duration and quality; panel (D) use of digital devices and risk of addiction.

Data on sleep revealed that 62.7% of the sample had a sleep duration of less than 8 hours per night and 40.1% slept less than before pandemic, with 28.9% of the adolescents reporting a deterioration in sleep quality (figure 3C).

Compared with the pre-pandemic period, the use of digital devices increased for study, for fun and out of boredom in 75.1%, 59.6% and 56.8% of the sample. The test for smartphone addiction revealed a risk of addiction in 45.9% of the adolescents (figure 3D). During the last 2 weeks prior to the completion of the online survey, 65.1% of the sample reported experiencing a high level of stress, anxiety or unhappiness or having difficulties coping with everyday activities. Among them, 77% reported that such feelings created a moderate-to-high level of interference in their quality of life, mainly due to school pressure.

On multivariate analysis, higher EHI was statistically associated with older age, female gender, lower consumption of UPFs, high level of cooking skills, good nutrition knowledge and absence of smartphone addiction.

Discussion

To the best of our knowledge, this is the first article exploring the change in the eating habits and lifestyle of a cohort of Italian adolescents, assessing the impact of 2 years of social restrictions of various kinds, due to the COVID-19 pandemic, and not only during or immediately after the strict lockdown period.

From a previous Italian study, with data collected from March to April 2020, we learnt that adolescents (aged between 12 and 17 years) had an increased intake of several unhealthy foods during the lockdown period, compared with the older population: they consumed more packaged sweets, industrial baked goods, soda beverages, salty snacks and sauces, and had a lower adherence to the Mediterranean diet.16 In our study, the median score of our EHI, close to the middle of the range, revealing neither a worsening nor an improvement in the overall quality of the diet, was due to the balance between the proportion of adolescents consuming more unhealthy foods and the proportion of those consuming more healthy foods. Moreover, the relative majority of the sample reported no variation in the consumption of each food category.

A multicentre study, including Italian adolescents, reported an increase in the daily consumption of sweets, fried foods and, in particular, of UPFs, during the lockdown period, compared with the previous period.17 One of the emerging concerns about diet quality, at any age, is the consumption of UPFs, since several epidemiological studies have reported an association between the extent of their consumption and increased incidence of chronic diseases and even overall mortality.18 Over a 2-year period, in our sample, the percentage of adolescents who reported consuming UPFs daily increased, with a greater relative increase in the rate of adolescents consuming these foods more than thrice a day (from 16.2% to 22.7%). This is one of the most worrying long-term consequences of the change in food habits: excessive consumption of UPFs has detrimental consequences on energy intake and weight gain even in a short period, as demonstrated in a recent randomised clinical trial.19 Increase in UPFs consumption among adolescents is a matter of concern, since adolescence is a crucial period of life for the creation of stable lifestyle attitudes and eating habits choice.20

In contrast with the data about UPFs, an emerging positive attitude towards our adolescents’ involvement in meal preparation was detected: the percentage increased from 8% to 18% of the sample. As supported by other studies, the periods of home confinement created the opportunity to have more time for meal preparation and to learn some traditional or family recipes from their parents.21 Interestingly, the EHI score above 33, corresponding to the 75th percentile, was positively associated with both higher cooking skills, lower UPFs consumption and better nutrition knowledge, that is fundamental in translating theory in good diet practices,.22 We explored further association of cooking skills elsewhere.23

Concerning physical activity, most of the adolescents reported an unchanged or even an increased level in their physical activities. Despite the restriction of physical education and other recreational activities during school closure periods, this attitude does not seem to be long-term among the adolescents in our survey, although we found a high drop-out rate from sports clubs.

Approximately one-third and two-fifths of the sample reported an overall self-perceived worsening of sleep quality and a decrease in sleep duration, respectively, in comparison to the pre-pandemic period. This result, together with the data on digital device use, smartphone addiction and emotional distress, deserves attention because of the profound relationship between these aspects, particularly in adolescence, a crucial period for future mental health.24

We acknowledge some limitations that readers must consider, when interpreting our results.

One of the major limitations of the study is about its generalisability, since the survey was limited to one of the cities with the highest number of days of school closure. We can argue that we conducted the study where the long-term effect should be the worst among the country, but we hope that sharing these results and our methodology could be useful for other researchers to explore the same aspects in other Italian areas. We also acknowledge the limitation of the self-reported nature of the survey, with potential recall bias and subjectivity. Nevertheless, we found that scores of the EHI were significantly higher and lower among adolescents self-perceiving an improving and a worsening in their food quality, respectively, and we can argue that this correlation could be considered as a marker of internal concordance and reliability of the data obtained.

Another limitation was that our data about several aspects of lifestyle had a comparative value: we collected most of the data to assess a worsening or an improvement in lifestyle habits, compared with the pre-pandemic period, without an objective assessment of, for example, diet quality or physical activity. We acknowledge that this aspect could be severely criticised, but our main objective was to assess the impact of the pandemic and restriction measures on lifestyle and not an assessment of the actual diet quality and physical activity level among adolescents. Our results could be of value in case of future similar scenarios of confinements, in order to prevent shift to unhealthy behaviours.

The present study has several strengths. First, the sample size was one of the largest among adolescents in our country. Furthermore, the survey explored several aspects of daily life, including frequency of foods consumption, meal preparation and distribution throughout the day, cooking skills, food insecurity, physical and screen activity, sleep, alcohol and tobacco use, smartphone addiction and psychological distress, providing a unique contribution in the knowledge of the long-term impact of pandemic restrictions among adolescents. Being adolescence a crucial period of life for the development of lifestyle, a deep understanding of the changes due to the recent pandemic is of primary importance in planning health prevention strategies.

Conclusions

Among a large cohort of adolescents, the long-term consequences of COVID-19 pandemic restrictions on lifestyle are diverse and mixed. The overall quality of the diet seems to be unchanged in comparison to the pre-pandemic period, with some adolescents’ positive attitude towards home cooking; nevertheless, a worrying increase in UPFs consumption may lead to both short-term and long-term detrimental health consequences and may deserve close monitoring. The influence of the pandemic on other aspects of lifestyle, such as physical activity, sleep quality, alcohol and tobacco use, and especially emotional distress, needs further investigation because of its possible link to both physical and mental well-being of the next generation.