Abstract
Aim; This study was planned and conducted to examine the change in food consumption and nutritional supplement use during the COVID-19 pandemic according to individuals’ status of anxiety and Mediterranean diet adherence. Methods; This prospective, cross-sectional research was completed online with the participation of 949 people (66.4% women). The Mediterranean Diet Adherence Screener Scale (MEDAS) and Coronavirus Anxiety Scale (CAS) were applied. After this section of the questionnaire was completed, the participants were tasked with answering questions regarding changes in food consumption and use of nutritional supplements during the pandemic. Results; While 50.8% of the participants had low adherence to the Mediterranean diet, 18.2% were considered to have a high adherence. It was observed that legume (p = 0.001), milk and dairy (p = 0.01), and fruit (p < 0.001) consumption of participants with high adherence to the Mediterranean diet increased during the pandemic, and packaged food (p < 0.001) consumption decreased. The increase in the consumption of fruit (p < 0.001) and vegetables (p = 0.018) were significantly higher in the group with anxiety. Age, sex, educational status, positive COVID-19 test, place of residence, CAS score and MEDAS score affect the use of dietary supplements according to binary logistic regression (R2 = 0.106 p < 0.001). The three most commonly used supplements were identified as vitamins C, D and B12. Conclusions: These results can shed light on how to prepare for possible future pandemics when it comes to dealing with anxiety through diet.
Keywords: Covid-19, Anxiety, Nutrition, Nutritional supplement, Mediterranean diet
1. Introduction
The global epidemic caused by the novel Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) caused lockdowns and forced changes to the lifestyles of people all over the world. In many countries, public indoor and outdoor gatherings were prohibited, so people had to spend most of their time at home. This social isolation also negatively affected mental health and eating habits [1].
Anxiety regarding being infected with SARS-CoV-2 required people to take extra precautions such as avoiding crowds, social distancing, and contact tracing [2]. Maintaining a healthy diet is important to support a strong immune system. In addition, institutions such as the World Health Organization (WHO) and the Food and Agriculture Organization (FAO) published recommendations emphasizing the importance of a healthy diet during this period [3,4]. One of the most important approaches that include these nutritional recommendations is the Mediterranean Diet (MD). The MD is characterized by a high content of plant-based foods, olive oil as the main source of fat, a low-to-moderate intake of fish, dairy products, and poultry, and a lessened consumption of red and processed meat [5]. Because MD is a diet rich in many macro and micronutrients and bioactive compounds, it reduces the inflammatory response, and oxidative stress and supports the immune system [6]. Mediterranean Diet's healthy food pattern shows a protective effect against many diseases such as diabetes, cardiovascular diseases, and cancer [7]. In addition to these, the anti-inflammatory and immunomodulatory effects of MD not only show protective effects against COVID-19 [8] but also reduce the severity of the disease [9,10].
Dietary supplements (DS) refer to non-drug dietary ingredients (vitamins, minerals, amino acids, herbs, etc.) that are often used to improve health and well-being [11]. The dietary supplement market is a billion-dollar global market with steady growth [12]. In particular, COVID-19 has significantly increased consumers' demand for DS. In the United States, 6 weeks after the onset of COVID-19, DS and nutraceutical sales increased by 44% ($435 million) from the previous year [13]. Suggestions that nutrition can be protective against COVID-19 by supporting the immune system [14,15] have been effective in this. During this period, consumers showed great interest in supplements and herbs such as vitamin C, vitamin D, zinc, selenium, turmeric, and garlic, especially to support the immune system [16]. Indeed, studies have shown that some vitamins, minerals, and nutrients can be protective against COVID-19 and reduce the severity of the disease. Their possible mechanisms of action against COVID-19 have been explored in many studies [[17], [18], [19]]. However, there is no definitive recommendation for the use of any DS in the treatment of COVID-19 [20].
The atmosphere of panic combined with the onset of restrictions during the first few months of the pandemic led to high levels of depression and anxiety [21]. Studies showed that higher stress scores were associated with higher caloric intake [22], insinuating that anxiety is one of the most important factors when considering increased hunger [23]. Pellegrini et al. [24] showed that self-reported anxiety/depression and unhealthy food choices were significantly associated with weight and body mass index (BMI) increase.
Considering the effect of COVID-19 on anxiety and nutritional behaviors, this study was planned and conducted to examine the change in food consumption and nutritional supplement use during the pandemic according to the status of anxiety and MD adherence.
2. Methods and materials
2.1. Study setting and population
This prospective, cross-sectional and online study was approved by the Ankara University Ethics Committee (approval number: 56786525–050.04.04), by the Declaration of Helsinki. It was also approved by Turkey's Health Ministry (Approval number: 20210423-T16-14-59). Participants were recruited via online platforms (Facebook, Instagram, e-mail, etc.). Informed consent was obtained from each participant. Those under the age of 18 were excluded from the study. The research data were collected between September 2020 and February 2021.
A post hoc Gpower analysis was carried out to determine whether the study had adequate power. According to the relationship between MEDAS and CAS; the effect size was calculated to be 0.1129822. And the post hoc power of the study (1 - β) was 0.968 (α = 0.05). Therefore, it is concluded that the study had an 97% probability of detecting the observed difference.
A questionnaire form consisting of five parts was administered to all participants. In the first part, demographic information about the participants regarding habits such as smoking, and anthropometric measurements of body weight and height were questioned. The second part covered the Mediterranean Diet Adherence Screener scale, and in the third part the Coronavirus Anxiety Scale was applied. The goal of the fourth section was to acquire information from the participants on whether or not they experienced a change in their food consumption during the pandemic. And the fifth and final section asked about nutritional supplementation.
2.2. Instruments
2.2.1. Mediterranean Diet Adherence Screener (MEDAS)
In the study, the Mediterranean Diet Adherence Scale was used to measure how closely individuals observed and followed the dietary recommendations. This scale was developed by Martinez-Gonzalez et al. and consists of 14 questions in total [25]. The validity and reliability study for our country was conducted by Pehlivanoğlu et al. in 2019. Having a total score of ≤5 on the scale signifies low adherence, between 6 and 9 qualifies as medium adherence, and ≥10 is considered high adherence to the diet [26].
2.2.2. Coronavirus anxiety scale (CAS)
The coronavirus anxiety scale (CAS), a short mental health screening tool, was developed by Lee to identify possible cases of dysfunctional anxiety associated with the Covid-19 crisis [27]. The scale is a 5-point Likert-type, one-dimensional scale. Scores on the scale range from “0” “never”, “1” “Rarely, less than one or two days”, “2” “A few days”, “3” “more than 7 days” and “4” “almost daily in the last two weeks”. The lowest value that can be obtained is 0 points, and the highest value is 20 points. An increase in the total score obtained from the scale indicates an increase in the level of anxiety, while 9 points can be used as a cut-off to define the group with and without anxiety. The reliability and validity of the CAS in Turkish were published by Evren et al. in 2020 [28].
2.2.3. Consumption changes
An eight-item questionnaire was used to reveal the change in food consumption following the onset of the COVID-19 pandemic. For each item, the participants were able to choose among “my consumption decreased”, “my consumption increased” or “my consumption did not change” during the pandemic period. Food groups questioned within the present research were: milk and dairy products (yogurt and cheese), meats (included fish, chicken) and egg, legumes, bread and grain products, vegetables, fruits, black tea and coffee and packaged foods.
2.2.4. Evaluation of using nutritional supplementation
Usage of nutritional supplements by individuals during the pandemic was also examined. Questions were directed to uncover preferred nutritional supplements and their sources of recommendation, along with where and how to purchase them.
2.3. Statistical analysis
SPSS software was used for the statistical evaluation of the data. In the descriptive analysis of the data, number (n), percentage (%), mean, and standard deviation values were used. The Kolmogorov-Smirnov and Shapiro-Wilk tests were used to determine whether data had a normal distribution. Pearson's chi-square test was used for comparisons of qualitative data. Binary logistic regression analysis for some independent variables and the using nutritional supplements during COVID-19 pandemic (dependent variable) was also performed. For all tests, p < 0.05 was considered statistically significant.
3. Results
The study was comprised of 630 women (66.4%) and 319 men (33.6%) participants aged 18–59 years. Examination of the current sample about demographic and lifestyle characteristic by sex is given in Table 1 . Most of the them had received a university education. When the BMI are examined, it is seen that the majority are of normal weight. Out of all the participants, 21.3% of the men and 18.6% of the women declared that they had been infected by COVID-19 before.
Table 1.
Examination of the current sample about demographic and lifestyle characteristic by sex.
| Men (n = 319) | Women (n = 630) | Total (n = 949) | |
|---|---|---|---|
| Age (year) | 28.3 (8.1) | 26.5 (8.1) | 27.1 (8.2) |
| Body weight (kg) | 78.0 (12.5) | 62.3 (22.9) | 67.5 (21.3) |
| Weight change during pandemic | |||
| -Gained weight | 95 (30%) | 210 (33.3%) | 305 (32.1%) |
| -Lost weight | 28 (8.8%) | 134 (21.3%) | 162 (17.1%) |
| -Maintained weight | 196 (61,2%) | 286 (45,5%) | 467 (50,8%) |
| Body height (cm) | 177.2 (7.3) | 163.6 (5.9) | 168.2 (9.1) |
| Nutritional status | |||
| -Underweight (BMI <18.5) | 7 (2.2%) | 60 (9.5%) | 67 (7.1%) |
| -Normal weight (18.5 ≤ BMI <25.0) | 170 (53.3%) | 409 (64.9%) | 579 (61.0%) |
| -Pre-obesity (25.0 ≤ BMI <30.0) | 110 (34.5%) | 110 (17.5%) | 220 (23.2%) |
| -Obesity (BMI >30.0) 23 2.9 | 32 (10.0%) | 51 (8.1%) | 83 (8.7%) |
| Educational Status | |||
| -Non-educated | 4 (1.3%) | 15 (2.4%) | 19 (2.0%) |
| -Primary school | 20 (6.3%) | 34 (5.4%) | 54 (5.7%) |
| -High school | 84 (26.3%) | 220 (34.9%) | 304 (32.0%) |
| -University | 211 (66.2%) | 361 (57.3%) | 572 (60.3%) |
| Working Status | |||
| -Working from home (online) | 35 (11.0%) | 162 (25.7%) | 197 (20.8%) |
| -Go to work | 216 (67.7%) | 200 (31.7%) | 416 (43.8%) |
| -Housemaker | 68 (21.3%) | 268 (42.5%) | 336 (35.4%) |
| Chronic Diseases | |||
| -Yes | 39 (12.2%) | 103 (16.3%) | 142 (15.0%) |
| Smoking | |||
| -Ex-smoker | 58 (18.2%) | 71 (11.3%) | 129 (13.6%) |
| -Yes | 143 (44.8%) | 94 (14.9%) | 237 (25.0%) |
| Place of Residence | |||
| -Alone | 53 (11.0%) | 25 (4.0%) | 60 (6.3%) |
| -With family | 253 (79.3%) | 592 (94.0%) | 845 (89.0%) |
| -With friends | 31 (9.7%) | 13 (2.1%) | 44 (4.6%) |
| Positive Covid-19 test | |||
| -Yes | 68 (21.3%) | 117 (18.6%) | 185 (19.5%) |
| MEDAS | |||
| -low adherence (score ≤5) | 193 (60.5%) | 289 (45.9%) | 482 (50.8%) |
| -medium adherence (score 6–9) | 84 (26.3%) | 210 (33.3%) | 294 (31.0%) |
| -high adherence (score ≥10) | 42 (13.2%) | 131 (20.8%) | 173 (18.2%) |
| CAS Score | 1.2 (2.7) | 2.5 (3.4) | 2.1 (3.2) |
Continuous variables are presented as mean with standard deviation (SD) and data are given as number (percent) for the following variables: weight change during pandemic, nutritional status, educational status, working status, chronic diseases, smoking, place of residence, positive Covid-19 test, MEDAS.
BMI; body mass index, MEDAS; Mediterranean Diet Adherence Screener, CAS; Coronavirus Anxiety Scale.
It was determined that individuals with a high adherence to the MD during the pandemic (according to MEDAS) experienced a higher increase in consumption of milk and dairy products (p = 0.010), and a smaller increase in consumption of legumes (p = 0.001) (Table 2 ). The groups whose tea and coffee consumption increased the most were the group whose adherence to the Mediterranean diet was classified as low and moderate (p = 0.010) (Table 2).
Table 2.
Changes in food consumption in Covid-19 pandemic according to MEDAS.
| Food Intake | Mediterranean diet adherence |
||||
|---|---|---|---|---|---|
| Low (n = 482) | Medium (n = 294) | High (n = 173) | |||
| Milk & dairy products | Increased | 203 (42.1)a | 115 (39.1)a | 87 (50.3)b | x2 = 13.226 p¥= 0.010 |
| Decreased | 39 (8.1)a | 12 (4.2)a | 6 (3.5)a | ||
| Unchanged | 240 (49.8)a | 167 (56.8)a | 80 (46.2)a | ||
| Meats & egg | Increased | 216 (44.8) | 117 (39.8) | 85 (49.1) | x2 = 4.183 p¥ = 0.382 |
| Decreased | 40 (8.3) | 26 (8.8) | 12 (6.9) | ||
| Unchanged | 226 (46.9) | 151 (51.4) | 76 (43.9) | ||
| Legumes | Increased | 149 (30.9)a | 91 (31.0)a | 73 (42.2)a | x2 = 19.836 p¥ = 0.001 |
| Decreased | 75 (15.6)a | 31 (10.5)b | 8 (4.6)b | ||
| Unchanged | 158 (53.5)a | 172 (58.5)a | 92 (53.2)a | ||
| Bread & Grain products | Increased | 170 (35.3) | 91 (31.0) | 46 (26.6) | x2 = 7.710 p¥ = 0.103 |
| Decreased | 99 (20.5) | 59 (20.1) | 48 (27.7) | ||
| Unchanged | 213 (44.2) | 144 (49.0) | 79 (45.7) | ||
| Vegetables | Increased | 212 (44.0)a | 143 (48.6)a | 108 (62.4)b | x2 = 31.354 p¥<0.001 |
| Decreased | 57 (11.8)a | 16 (5.4)b | 3 (1.7)b | ||
| Unchanged | 213 (44.2)a | 135 (45.9)a | 62 (35.8)a | ||
| Fruits | Increased | 262 (54.4)a | 182 (61.9) ab | 122 (70.5)b | x2 = 23.455 p¥<0.001 |
| Decreased | 46 (9.5)a | 10 (3.4)b | 6 (3.5)b | ||
| Unchanged | 174 (36.1)a | 102 (34.7) ab | 45 (26.0)b | ||
| Black tea & coffee | Increased | 249 (51.7)a | 139 (47.3)a | 86 (49.7)a | x2 = 13.377 p¥ = 0.010 |
| Decreased | 58 (12.0)b | 28 (9.5)b | 33 (19.1)a | ||
| Unchanged | 175 (36.3)b | 127 (43.2)b | 54 (31.2)a | ||
| Packaged food | Increased | 143 (29.7)a | 69 (23.5)ab | 28 (16.2)b | x2 = 25.887 p¥<0.001 |
| Decreased | 141 (29.3)a | 111 (37.8)b | 84 (48.6)b | ||
| Unchanged | 198 (41.1)a | 114 (38.8)a | 61 (35.3)a | ||
¥Chi-square test (post hoc, Bonferroni method); different letters (a, b) represent statistically significance.
While the consumption of bread and grain products increased more in individuals without anxiety (p = 0.006), the consumption of milk and dairy products increased more (p = 0.043). The increase in consumption of fruits was also statistically significantly higher in the group without anxiety (p < 0.001). The detailed data is shown in Table 3 .
Table 3.
Changes in food consumption in Covid-19 pandemic according to CAS.
| Food Intake | Coronavirus Anxiety Scale |
Pa | ||
|---|---|---|---|---|
| Anxiety (n = 783) | Non-anxiety (n = 166) | |||
| Milk & dairy products | Increased | 320 (40.9)a | 85 (51.2)b | x2 = 6.282 p = 0.043 |
| Decreased | 50 (6.4)a | 7 (4.2)a | ||
| Unchanged | 413 (52.7)a | 74 (44.6)a | ||
| Meats & egg | Increased | 337 (43.0) | 81 (48.8) | x2 = 3.963 p = 0.138 |
| Decreased | 61 (7.8) | 17 (10.2) | ||
| Unchanged | 385 (49.2) | 68 (41.0) | ||
| Legumes | Increased | 249 (31.8) | 64 (38.6) | x2 = 3.849 p = 0.146 |
| Decreased | 92 (11.7) | 22 (13.3) | ||
| Unchanged | 442 (56.4) | 80 (48.2) | ||
| Bread & Grain products | Increased | 237 (30.3)a | 70 (42.2)b | x2 = 10.201 p = 0.006 |
| Decreased | 170 (21.7)a | 36 (21.7)a | ||
| Unchanged | 376 (48.0)a | 60 (36.1)b | ||
| Vegetables | Increased | 366 (46.7)a | 97 (58.4)a | x2 = 8.019 p = 0.018 |
| Decreased | 63 (8.0)a | 13 (7.8)a | ||
| Unchanged | 354 (45.2)a | 56 (33.7)b | ||
| Fruits | Increased | 445 (56.8)a | 121 (72.9)b | x2 = 15066 p < 0.001 |
| Decreased | 53 (6.8)a | 9 (5.4)a | ||
| Unchanged | 285 (36.4)a | 36 (21.7)b | ||
| Black tea & coffee | Increased | 374 (47.8)a | 100 (60.2)b | x2 = 8.999 p = 0.011 |
| Decreased | 100 (12.8)a | 19 (11.4)a | ||
| Unchanged | 309 (39.5)a | 47 (28.3)b | ||
| Packaged food | Increased | 184 (23.5)a | 56 (33.7)b | x2 = 8.182 p = 0.017 |
| Decreased | 280 (35.8)a | 56 (33.7)b | ||
| Unchanged | 319 (40.7)a | 54 (32.5)b | ||
Chi-square test (post hoc, Bonferroni method); different letters (a, b) represent statistically significance.
All in all, 42.5% of the individuals participating in the study declared that they used nutritional supplements. This rate makes up 47% of the women and 34% of the men. The top three nutritional supplements most frequently used by women were vitamin C, vitamin D and ginger, respectively. Men, on the other hand, often preferred vitamin C, vitamin D and linden. Details about the use of nutritional supplements are given in Table 4 .
Table 4.
Examination of dietary supplement use status.
| Men (n = 319) | Women (n = 630) | Total (n = 949) | |
|---|---|---|---|
| Using nutritional supplements | |||
| -Yes | 108 (34) | 296 (47) | 404 (42.5) |
| -No | 211 (66) | 334 (53) | 545 (57.5) |
| x2 = 17.057 p < 0.001 | |||
| Type of nutritional supplementsa | |||
| -Vitamin C | 78 (24.5) | 171 (27.1) | 249 (26.2) |
| - Vitamin D | 53 (16.6) | 156 (24.8) | 209 (22.0) |
| - Vitamin B12 | 36 (11.3) | 92 (14.6) | 128 (13.5) |
| -Multivitamin | 20 (6.3) | 53 (8.4) | 73 (7.7) |
| - Iron | 18 (5.6) | 61 (9.7) | 79 (8.3) |
| -Zinc | 18 (5.6) | 48 (7.6) | 66 (7.0) |
| -Calcium | 11 (3.4) | 24 (3.8) | 35 (3.7) |
| -Omega-3 | 22 (6.9) | 49 (7.8) | 71 (7.5) |
| -Probiotics | 10 (3.1) | 33 (5.2) | 43 (4.5) |
| -Prebiotics | 1 (0.3) | 11 (1.7) | 12 (1.3) |
| -Propolis | 8 (2.5) | 35 (5.6) | 43 (4.5) |
| -Cinnamon | 21 (6.6) | 86 (13.7) | 107 (11.3) |
| -Oregano | 45 (14.1) | 99 (15.7) | 144 (15.2) |
| -Linden | 47 (14.7) | 113 (17.9) | 160 (16.9) |
| -Ginger | 33 (10.3) | 122 (19.4) | 155 (16.3) |
| -Turmeric | 20 (6.3) | 96 (15.2) | 116 (12.2) |
| -Sage | 29 (9.1) | 82 (13.0) | 111 (11.7) |
| By whose recommendationa | |||
| -Doctor | 27 (8.5) | 106 (16.8) | 133 (14.0) |
| -Dietitian | 10 (3.1) | 39 (6.2) | 49 (5.2) |
| -Pharmacist | 21 (6.6) | 66 (10.5) | 87 (9.2) |
| -Nurse | 8 (2.5) | 17 (2,7) | 25 (2.6) |
| -Social Media | 27 (8.5) | 47 (7.5) | 74 (7.8) |
| -Relatives | 40 (12.5) | 93 (14.8) | 133 (14.0) |
| -Newspaper | 10 (3.1) | 4 (0.6) | 14 (1.5) |
| -Scientific journal | 19 (6.0) | 35 (5.6) | 54 (5.7) |
| -Television commercial | 13 (4.1) | 17 (2.7) | 30 (3.2) |
| Place of purchasea | |||
| -Herbal product store | 23 (7.2) | 46 (7.3) | 69 (7.3) |
| -Pharmacy | 55 (17.2) | 198 (31.4) | 253 (26.7) |
| -Online platforms | 17 (5.3) | 37 (5.9) | 54 (5.7) |
| -Supermarket | 26 (8.2) | 65 (10.3) | 91 (9.6) |
| -Herbalist | 52 (16.3) | 128 (20.3) | 180 (19.0) |
| Consideration when purchasinga | |||
| -Price | 19 (6) | 46 (7) | 65 (6.8) |
| -Brand | 25 (8) | 87 (14) | 112 (11.8) |
| -Quality | 76 (24) | 219 (35) | 295 (31.1) |
| -Naturalness | 69 (22) | 199 (32) | 268 (28.2) |
| -Being locally produced | 21 (7) | 35 (6) | 56 (5.9) |
Data are given as number (percent).
Participants were able to choose more than one option.
Binary logistic regression was used to investigate factors affecting the use of nutritional supplements during the COVID-19 pandemic. A significant regression was found with an R2 value of 0.106 (p < 0.001) (Table 5 ). According to binary logistic regression, for every increase in age 0.972 more likely that a person will use nutritional supplements (p = 0.003). It is also seen that womens are likely to use nutritional supplements (OR = 0.554, p = 0.007). Each increase in the CAS score (OR = 0.935, p = 0.002) and the MEDAS score (OR = 0.878, p < 0.001) increases the use of dietary supplements. The regression analysis shows that neither chronic diseases, smoking, nor weight, height, BMI or weight change were significantly associated with the use of nutritional supplements (Table 5).
Table 5.
Binary logistic regression; dependent variable is using dietary supplements during Covid- 19 pandemic.
| Covariates | B | SE | Wald | P | OR | 95% CI |
|
|---|---|---|---|---|---|---|---|
| LL | UL | ||||||
| Age | −0.028 | 0.010 | 8.632 | 0.003 | 0.972 | 0.954 | 0.991 |
| Sex | −0.591 | 0.220 | 7.188 | 0.007 | 0.554 | 0.360 | 0.853 |
| Educational status | −0.283 | 0.084 | 11.272 | 0.001 | 0.754 | 0.639 | 0.889 |
| Chronic diseases | −0.019 | 0.201 | 0.009 | 0.926 | 0.982 | 0.662 | 1.456 |
| Smoking | −0.023 | 0.089 | 0.066 | 0.798 | 0.978 | 0.822 | 1.163 |
| Positive Covid-19 test | 0.206 | 0.070 | 8.616 | 0.003 | 1.228 | 1.071 | 1.409 |
| Place of residence | 0.447 | 0.215 | 4.340 | 0.037 | 1.564 | 1.027 | 2.383 |
| Weight | 0.002 | 0.054 | 0.001 | 0.975 | 1.002 | 0.901 | 1.114 |
| Height | −0.011 | 0.044 | 0.067 | 0.796 | 0.989 | 0.906 | 1.078 |
| BMI | 0.000 | 0.153 | 0.000 | 0.998 | 1.000 | 0.742 | 1.350 |
| Weight change | 0.077 | 0.070 | 1.212 | 0.271 | 1.080 | 0.942 | 1.239 |
| CAS score | −0.067 | 0.022 | 9.470 | 0.002 | 0.935 | 0.896 | 0.976 |
| MEDAS score | −0.130 | 0.034 | 14.209 | <0.001 | 0.878 | 0.821 | 0.940 |
| Nagelkerke's R2 = 0.106 p < 0.001 | |||||||
B = regression coefficient, SE = standard error, OR = odds ratio, CI = confidence interval, LL = lower limit, UL = upper limit, BMI; body mass index, MEDAS; Mediterranean Diet Adherence Screener, CAS; Coronavirus Anxiety Scale.
4. Discussion
The MD is protective against many non-communicable diseases, as well as its positive effects on the immune system, suggesting that this diet style is also protective against COVID-19, as shown in studies [[8], [9], [10]]. This cross-sectional study assessed the effect of adherence to the MD and COVID-19-related anxiety on food consumption and DS use. To the best of our knowledge, this is the first study in Turkey that examined these relationships during the pandemic. Our study shows that individuals with a high adherence to the MD during the pandemic experienced a higher increase in consumption of vegetables, fruits, milk and dairy products. The increase in fruit and vegetable consumption during this period was also found in other studies [[29], [30], [31], [32]]. However, most of the participants in our study had a low adherence to MD. This is surprising because the majority of our participants have a high level of education, which is associated with high adherence to MD [33,34]. Despite this, a significant group of these people reported an increase in the consumption of fruits, vegetables and grains. However, during the COVID-19 pandemic, changes in dietary pattern are not always healthy. A decrease in diet quality and unhealthy eating behaviors were also observed during COVID-19 [35,36]. In our population, the increase in the consumption of packaged foods was mostly in the group with low adherence to MD. Thus, high adherence to MD is associated with increased consumption of healthy foods compared to those with low adherence.
During the COVID-19 period, the prevalence of anxiety reached 31.9%, making it another important health problem [37]. It is well-known that diet and psychological health affect each other. Diet quality during the pandemic was inversely associated with moderate-to-severe anxiety [38]. While a healthy and balanced diet can reduce anxiety levels [39], higher levels of anxiety were associated with a greater consumption of fried foods, pastries, and sugar-sweetened beverages [40]. In fact, each point increase in MD score was associated with an almost 7% decrease in the odds of moderate to severe anxiety [38]. The present study showed that people with anxiety increased their intake of packaged foods, milk and dairy, bread and grains, vegetables, fruits, and black tea and coffee compared to people without anxiety. In parallel with our result, Kaya et al. [41] reported that elevated anxiety scores were associated with an increased consumption of fruit, milk, cheese, fruit, and vegetables during the COVID-19 pandemic. Interestingly, fruit and vegetable consumption were also often associated with a better mood [42,43]. This difference may be related to the overall dietary pattern because only 18.2% of our participants had a high adherence to the MD. In addition, weight gain is also associated with anxiety [38]. We determined that the rate of those who reported gaining weight was 32.3%. Studies conducted in different countries show that the rate of weight gain was as high as 30–48.3% during COVID-19 pandemic [[44], [45], [46], [47]]. Different risk factors that cause weight gain during COVID-19, such as length of stay-at-home mandate, increased snacking (particularly after dinner), and being overweight/obese [24,46,48,49].
COVID-19 has generated a great interest in immune system-related nutrients and bioactive components such as vitamin C and D, zinc, fish oil, probiotics, multivitamins, selenium, ginger and garlic [16,50]. According to Google Trend analysis, people's interest in the search terms “coronavirus” and “immunity”, and herbal products increased during this period [51]. In a previous study, it was found that almost half of the participants increased their use of supplements during the pandemic period [52]. Indeed, it has been shown that vitamins and minerals such as vitamin C, vitamin D, vitamin B12, iron, zinc may be beneficial in the management of COVID-19 [[53], [54], [55]], and their immunomodulatory effects are well known [[17], [18], [19]]. Still, there is no effective DS used in the treatment of COVID-19 [20]. Moreover, the benefit of using DS for people who are not at risk of deficiencies in these nutrients is questioned. In our study, 34.7% of the participants reported using DS. This rate is considerably higher than the 9.7% DS use rate reported in Turkey [56]. Undoubtedly, the impact of the COVID-19 pandemic is high. It has been reported that DS use has increased in Turkish adults with the COVID-19 pandemic, and these rates have changed between 26.7% and 66.2% [[57], [58], [59], [60]]. Also, the rate of DS use was higher in women, similar to the results of other studies [57,58]. The most preferred DS in our study for men were vitamin C, vitamin D, linden and oregano; for women, they were vitamin C, vitamin D, ginger and linden. Vitamins C and D are among the most commonly used DS in other studies [57,58,[60], [61], [62], [63]]. We also found that age, educational status, positive COVID test result, place of residence, CAS and MEDAS scores were the factors affecting the use of DS. In parallel with our results, sex, age, educational status, positive COVID-19 test were reported as factors affecting DS use [57,58,61,64]. However, how these factors affect DS use is controversial. Increasing the level of education may or may not affect DS use [58,61,63]. Similarly, DS use may be high among women [57,65] or men [61]. Similar contradictions apply to young and old individuals [65,66]. As can be seen, the same factors may affect the use of DS differently. Exceptionally, having or being in contact with COVID-19 consistently increases DS use [57,61,63,64]. In this respect, it may be useful to investigate concepts such as health or nutritional literacy in addition to sociodemographic factors. According to our results and other studies [67], people follow the guidance of friends or relatives about the use of DS. Given that participants do not have enough knowledge about DS [63], this may increase the risk of spreading misinformation about COVID-19.
The present study had several limitations. Weight was self-reported and not measured; similarly, self-reported questionnaires were used. The study included retrospective data based on the respondents’ memory. Finally, the research tool, the electronic questionnaire, was more often completed by respondents with a higher-level education from larger cities. This likely had to do with quality of internet.
In conclusion, to the best of our knowledge, this is the first study that examining the relationship between DS use and change in food consumption according to adherence to the MD during the COVID-19 pandemic in Turkey. Although Turkey is in a geographical location suitable for the MD, it is thought that the low level of adherence to the diet may be due to the economic and supply-related problems that arose during the pandemic. However, the relationship between changes in food consumption and supplement use with the MD and anxiety was shown in the study. These results may prove useful in the coming years, as they can be used in the development of policies and measures that will better prepare us for another pandemic.
Conflicts of interest and source of funding
The authors have disclosed that they have no significant relationships with, or financial interest in, any commercial companies pertaining to this article. This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.
Ethical approval
The study complied with the World Medical Association Declaration of Helsinki regarding ethical conduct of research involving human subjects. The research was approved by Ankara University Ethics Committee (approval number: 56786525–050.04.04).
Contributor's statement
G. D., C. Ö. and N. Y. A. contributed to the conception and design of the research. G. D. and C. Ö. contributed to interpretation. G. D. and C. Ö. drafted the manuscript. All authors critically revised the manuscript, gave the final approval and agrees to be accountable for all aspects of work ensuring integrity and accuracy.
Sources of support
This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.
Author declarations
The authors have no conflicts to declare.
Acknowledgements
The authors would like to thank Beyza DURAK and Özge CAN for their assistance in data collection.
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