Occupational 2015;65:477–484 Advance Access publication 9 June 2015 doi:10.1093/occmed/kqv068

Nutrition and health in hotel staff on different shift patterns

R. Seibt1, T. Süße1, S. Spitzer1, B. Hunger2 and M. Rudolf3 1Faculty of Medicine, Institute and of Occupational and , Technical University of Dresden, Fetscherstrasse 74, 01307 Dresden, Germany, 2Government Safety Organisation Foods and Restaurants (BGN), German Social Accident Insurance Institution for the Foodstuffs and Catering Industry (ASD*BGN), Office of Coordination Potsdam, 14480 Potsdam,

Germany, 3Department of , Institute of General Psychology, Biopsychology and Methods of Psychology, Technical Downloaded from University of Dresden, 01069 Dresden, Germany. Correspondence to: R. Seibt, Faculty of Medicine, Institute and Clinic of Occupational and Social Medicine, Technical University of Dresden, Fetscherstrasse 74, 01307 Dresden, Germany. Tel: +49 351 3177 452; fax: +49 351 3177 459; e-mail: [email protected] http://occmed.oxfordjournals.org/

Background Limited research is available that examines the nutritional behaviour and health of hotel staff work- ing alternating and regular shifts. Aims To analyse the nutritional behaviour and health of employees working in alternating and regular shifts. Methods The study used an ex post facto cross-sectional analysis to compare the nutritional behaviour and health parameters of workers with alternating shifts and regular shift workers. Nutritional behaviour was assessed with the Food Frequency Questionnaire. Body dimensions (body mass index, waist

hip ratio, fat mass and active cell mass), metabolic values (glucose, triglyceride, total cholesterol at University of California, Santa Barbara on August 23, 2015 and low- and high-density lipoprotein), diseases and health complaints were included as health parameters. Results Participants worked in alternating (n = 53) and regular shifts (n = 97). The average age of subjects was 35 ± 10 years. There was no significant difference in nutritional behaviour, most surveyed body dimensions or metabolic values between the two groups. However, alternating shift workers had significantly lower fat mass and higher active cell mass but nevertheless reported more pronounced health complaints. Sex and age were also confirmed as influencing the surveyed parameters. Conclusions Shift-dependent nutritional problems were not conspicuously apparent in this sample of hotel indus- try workers. Health parameters did not show significantly negative attributes for alternating shift workers. Conceivably, both groups could have the same level of knowledge on the health effects of and comparable opportunities to apply this. Further studies on nutritional and health behaviour in the hotel industry are necessary in order to create validated screening programmes. Key words Body dimensions; health; hotel; metabolic parameters; nutritional behaviour; restaurant; shift work.

Introduction Shift work is known to be associated with various health risks [5–8]. Associations between shift work and Shift work is an integral part of the hotel industry profile [1]. cardiovascular [7–9] and gastrointestinal diseases have As such, 67% of the labour force work at weekends and at been observed [5,10,11], but other health complaints are night. Other central characteristics in this industry include also more common among shift workers [12–14]. The temporary contracts, unpredictable working hours, fre- mismatch between shift working and human biological quent omission of breaks and often a precarious economic rhythms is thought to be a determining cause [5,11]. situation [2,3]. These issues may explain the low average Additionally, accidents and heightened or incorrect load- age of employees (36 years), and the high labour turnover, ing of the musculoskeletal system increase health risks with the average period of employment being 2–3 years [4]. among hotel industry employees [3].

© The Author 2015. Published by Oxford University Press on behalf of the Society of Occupational Medicine. All rights reserved. For Permissions, please email: [email protected] 478 OCCUPATIONAL MEDICINE

Unfavourable nutritional behaviour appears to con- occupational health and safety were regulated through the tribute significantly to the aetiology of health problems Government Safety Organization Foods and Restaurants associated with shift work [11]. Irregular food intake or (BGN), German Social Accident Insurance Institution missing meals and the consumption of cold foods that for the foodstuffs and catering industry (ASD*BGN). are rich in calories and hard to digest are not uncom- The survey period was from May to August 2012. The mon in shift workers [15–17]. Shift workers also engage data on nutritional behaviour and health were collected in more behaviours hazardous to health [5,11]. There is as part of an extended occupational health screening. also evidence that shift workers have more unfavourable Sociodemographic, occupational and health data were deviations in body dimensions [11,18,19] and metabolic collected using a modified shift worker questionnaire (R. values [11,19,20]. Hotel industry shift workers are also Seibt, S. Spitzer, unpublished data). The assignment to frequently exposed to environmental factors such as sec- one or other shift system was also determined through ond-hand smoke or alcohol intake [1,3]. this questionnaire. The Food Frequency Questionnaire

As the hotel industry takes care of clients’ board and by Westenhöfer [24] was used to assess nutritional behav- Downloaded from nutrition, its employees might be expected to show more iour. This questionnaire measures how often certain health-conscious nutritional behaviour, but the evidence foodstuffs from the following categories are consumed: does not support this. Novotny et al. [21] studied the grain products, milk products, animal products, vege­ nutritional behaviour and body dimensions of over- tables/fruits, fats and sweets (answer categories: from 2

weight (body mass index (BMI) > 25.0 kg/m ) of hotel several times a day to seldom/never). A ‘beverages’ cat- http://occmed.oxfordjournals.org/ employees on a Hawaiian island. They found that the egory was added for this survey. We also asked how regu- employees had an average BMI of 29.3 kg/m2 and an larly the survey participant had breakfast, lunch, dinner average waist height ratio of 0.56. The mean number of and snacks (answer categories: daily, more than twice a servings of sweetened beverages (lemonade, sweetened week, once or twice a week or never). Specific sum scores juices and teas) per day was 1.0 (recommendation: lit- were assigned to the answers. Based on the score in each tle or no sweetened beverages). The average number of category, the health-promoting effect of the respective servings of fruit was 2.9 (recommendation: 2–5) and of consumption pattern was evaluated on an ordinal scale meat 1.6 (recommendation: 2–3). Although no serious (Tables 2 and 3). Two indices were calculated from these

nutritional deficits were observed, body dimensions were data: the Diet Selection Index (DSI: range 0–4) and the at University of California, Santa Barbara on August 23, 2015 unfavourable. An earlier Hawaiian study of hotel employ- Regularity Index (RI: range 0–4). Higher values signify ees demonstrated a strong relationship between blood that diet selection and diet regularity are considered to pressure and obesity in women, whereas blood pressure be healthier. in men was associated with the central distribution of fat As health parameters, body dimensions (BMI, waist [22]. According to Bohle et al. [23], unpredictable work circumference, waist hip ratio (WHR), fat mass and active schedules are associated with unhealthy behaviours such cell mass) and metabolic parameters (glucose, triglycer- as irregular meals and lack of physical activity. ide, total cholesterol, low-density lipoprotein (LDL) and There is a lack of research on nutritional behaviour and high-density lipoprotein (HDL) and LDL:HDL ratio) health of shift workers in the hotel industry. The goal of this were included. The body composition was measured study was therefore to analyse systematically the nutritional with the Body Impedance Analyser (Corpus RX 4000, behaviour and health of employees working in two differ- Medical Healthcare GmbH). ent shift systems with particular emphasis on whether the Additionally data were collected with questionnaires nutritional behaviour and health of hotel staff working alter- on the number of medical diagnoses (Work Ability Index, nating shifts (AS, i.e. alternation of shifts at different times, subscale WAI 3, short version) [25] and the number and with night and weekend work) differed from employees characteristics of health complaints (Beschwerden-Liste, working regular shifts (RS, i.e. long-term work at regular B-L) [26]. The number of medical diagnoses ranged hours). We hypothesized that compared with RS work (after from 0 to 14. Characteristics of health complaints were controlling for sex and age), working AS is associated with scored on an ordinal scale (answer categories: from none to strong). These values were added to produce a total 1. nutritional behaviour that is hazardous to health score for health complaints. [11,15–17]; This study was conducted in conformance with the 2. body dimensions [11,18,19] and metabolic para­ guidelines of the World Medical Association (WMA) meters [11,19,20] that are disadvantageous to health Declaration of Helsinki and the ethical principles of and medical research involving human subjects amended by 3. more diseases and health complaints [5–7]. the Ninth WMA General Assembly, Seoul, Republic of Korea, October 2008. As a matter of legal succession, Methods it was funded by the Government Safety Organisation Foods and Restaurants in Mannheim. For this ex post facto cross-sectional analysis, we recruited Statistical analysis was conducted using the Statistical employees working AS and RS from 11 hotels, whose Package for the Social Sciences (SPSS Version 21.0) R. SEIBT ET AL.: NUTRITION AND HEALTH IN HOTEL STAFF 479 software. Variance analysis and ordinal and logistic was 35 ± 10 years (age range: 20–63) and did not differ were applied in the examination of significantly between groups. The average weekly work- differences in the variables of nutritional behaviour and ing time was 42 h, whereas the RS workers worked an health parameters between the shift groups. Statistical average of 3 h more per week (P < 0.01) and included adjustment for sex and age was conducted in all analy- more female employees (P < 0.01). On average, the ses since these covariates exert significant influence on employees had a working life of 16 years. No significant nutrition and health. difference in health behaviour between those working in the two shift systems was found. AS employees did not show more harmful behaviour regarding smoking, alco- Results hol consumption or physical activity compared with RS Table 1 shows the characteristics of the sample, which employees (Table 1). included 150 employees in the hotel industry (60 men Information on the consumption frequency of foods and 90 women). Fifty-three of them worked in AS (with- and the regularity of eating among the two shift groups Downloaded from out night work, but with weekend work) and 97 worked are listed in Tables 2 and 3, respectively. AS and RS in RS. The study participants worked in several differ- employees did not differ significantly in their nutritional ent positions representative of the various tasks in the behaviour in any of the observed variables (Tables 2 and hotel industry. The work areas included reception, cus- 3). The mean values of the DSI and the RI reveal that tomer care, housekeeping, restaurant/bar, bookkeep- employees in both shift groups had, on average, moder- http://occmed.oxfordjournals.org/ ing, maintenance and utilities management, personnel ately healthy to rather good nutritional behaviour. Both management, sales and marketing, event planning and groups showed generally good, although improvable warehouse management. The average age of the sample grain consumption, close to adequate milk product con- sumption, relatively adequate animal product consump- Table 1. Description of the sample tion, good to optimal fat consumption and acceptable beverage consumption (Table 2). AS (n = 53) RS (n = 97) Most employees in both of the groups had breakfast, lunch and dinner daily (Table 3). In comparison to the Total, n (%) 53 (35) 97 (65) AS group, the RS group showed a tendency to have at University of California, Santa Barbara on August 23, 2015 Sex snacks more frequently. Male, n (%) 29 (19) 31 (21) Sex and age had a significant influence on nutritional Female, n (%) 24 (16) 66 (44) behaviour. Compared with men, women consumed Age (years) Mean ± SD 33.7 ± 9.5 35.0 ± 10.2 somewhat fewer animal products, more fruit and vege­ Min.; Max. 20; 61 21; 62 tables and more sweets. Women also showed healthier Work-related factors beverage consumption. The regularity of eating breakfast Total working years or other meals increased with age, whereas the frequency Mean ± SD 15.0 ± 9.7 16.1 ± 10.6 of snacks decreased. Consumption of grain products also Min.; Max. 1; 42 0; 42 increased with age. Working years on current occupation (years) The health parameter results are shown in Table 4. Mean ± SD 7.0 ± 8.5 6.5 ± 6.8 There were no significant differences in body dimen- Min.; Max. 0; 37 0; 27 Mean weekly working time (number of hours) sions between both groups. Based on the BMI, both Mean ± SD 40.3 ± 6.1 43.4 ± 9.6 groups were slightly below the threshold for overweight 2 2 Min.; Max. 8; 60 4; 60 (means—AS: 24.0 kg/m ; RS: 25.0 kg/m ). As expected, Lifestyle factors women showed on average a lower BMI, a lower waist Smoking (number of cigarettes/day) circumference and a lower WHR than men. Waist cir- Mean ± SD 5.2 ± 7.0 4.6 ± 8.0 cumference and WHR increased with age. Min.; Max. 0; 20 0; 35 Work schedule was a significant factor in explaining Alcohol consumption (g/day) the variance for both fat mass (3%) and active cell mass Mean ± SD 6.2 ± 8.5 6.4 ± 8.6 Min.; Max. 0; 40.8 0; 40.8 (5%). Employees working AS showed a lower proportion Physical activity (number of hours/week) of fat mass and higher proportion of active cell mass. As Mean ± SD 2.6 ± 3.5 2.5 ± 2.4 expected, women had significantly lower active mass but Min.; Max. 0; 18 0; 12 higher fat mass than men. Age, on the other hand, had no influence on body composition (Table 4). Frequency distribution is described through the absolute number of participants in the subgroups and as a fraction of the total sample. For other characteristics, There were no significant differences between shift mean value (mean), standard deviation (SD), minimum (Min.) and maximum groups for metabolic parameters. Mean values illustrate that (Max.) are used. The effect of smoking was determined based on cigarettes all metabolic parameters were within their respective normal consumed per day. Data on alcohol consumption are presented as amount of pure alcohol per day (g). The effect of physical exercise is based on the reported ranges. Only the average total cholesterol values were slightly number of hours per week. high for both groups, being just below a health-endangering 480 OCCUPATIONAL MEDICINE

Table 2. Consumption frequency of food groups by shift group

2 Consumption frequency AS (n = 53) RS (n = 97) Test statistic P values η partial 95% CI

LH

Method scores [24] and ratinga Cereal products (number of points = 5.7 ± 1.7 6.2 ± 1.8 F = 1.821 NS 0.012 point score p.), mean ± SD 0–4 = 0 p. insufficient,n (%) 12 (23) 14 (14) W = 4.453 <0.05 0.743 0.053 1.434 5–7 = 1 p. good, n (%) 33 (62) 53 (55) 8–10 = 2 p. optimal, n (%) 8 (15) 30 (31) Dairy products (number of points = 11.5 ± 5.3 10.2 ± 4.4 F = 2.318 NS 0.016 point score p.), mean ± SD 0–9 = 0 p. insufficient,n (%) 22 (42) 53 (55) W = 3.877 <0.05 −0.656 −1.310 −0.003 Downloaded from 10–15 = 2 p. sufficient,n (%) 18 (34) 29 (30) 16–19 = 2 p. optimal, n (%) 9 (17) 13 (13) 20–26 = 1 p. excessive, n (%) 4 (8) 2 (2) Animal products (number of points = 14.3 ± 3.8 15.2 ± 3.1 F = 0.387 NS 0.003

point score p.), mean ± SD http://occmed.oxfordjournals.org/ 0–9 = 0 p. excessive, n (%) 5 (9) 6 (6) W = 0.020 NS −0.050 −0.737 0.637 10–15 = 2 p. good, n (%) 22 (42) 38 (39) 16–20 = 2 p. optimal, n (%) 26 (49) 53 (55) Fruits/vegetables (number of points = 5.2 ± 2.4 5.5 ± 2.1 F = 0.148 NS 0.001 point score p.), mean ± SD 0–2 = 0 p. insufficient,n (%) 9 (17) 8 (8) W = 0.000 NS 0.005 −0.679 0.690 3–6 = 1 p. good, n (%) 27 (51) 60 (62) 7–8 = 2 p. optimal, n (%) 17 (32) 29 (30) Fats (number of points = point score p.), 11.8 ± 2.8 12.2 ± 3.2 F = 1.296 NS 0.009 mean ± SD 3–8 = 0 p. excessive, n (%) 4 (8) 9 (9) W = 2.091 NS 0.503 −0.179 1.184 at University of California, Santa Barbara on August 23, 2015 9–11 = 1 p. good, n (%) 23 (43) 30 (31) 12–18 = 2 p. optimal, n (%) 26 (49) 58 (60) Sweets (number of points = score), mean ± SD 3.8 ± 3.4 4.2 ± 4.6 F = 0.000 NS 0.000 0–4 = 2 p. optimal, n (%) 38 (72) 63 (65) W = 0.060 NS 0.093 −0.650 0.836 5–7 = 1 p. acceptable, n (%) 10 (19) 26 (27) 8–30 = 0 p. excessive, n (%) 5 (9) 8 (8) Beverages (number of points = 43.8 ± 8.0 44.9 ± 8.2 F = 0.011 NS 0.000 point score p.), mean ± SD 0–25 = 0 p. less favourable, n (%) 1 (2) 1 (1) W = 0.002 NS −0.021 −0.908 0.867 26–50 = 1 p. acceptable, n (%) 43 (81) 77 (79) 51–70 = 2 p. optimal, n (%) 9 (17) 19 (20) Index of food choice (index value = score), 2.7 ± 0.6 2.77 ± 0.7 F = 0.390 NS 0.003 mean ± SD 0–2 = 0 very bad, n (%) 0 (0) 0 (0) W = 0.667 NS 0.197 −0.468 0.862 3–5 = 1 rather bad, n (%) 0 (0) 2 (2) 6–8 = 2 moderate, n (%) 21 (40) 30 (31) 9–11 = 3 rather good, n (%) 27 (51) 54 (56) 12–14 = 4 very good, n (%) 5 (9) 11 (11) Index of eating regularity (index value), 2.5 ± 1.0 2.7 ± 0.9 F = 0.831 NS 0.006 mean ± SD 0–2 = 0 very bad, n (%) 2 (4) 1 (1) W = 0.992 NS 0.324 −0.314 0.963 3–5 = 1 rather bad, n (%) 6 (11) 7 (7) 6–8 = 2 moderate, n (%) 20 (38) 32 (33) 9–11 = 3 rather good, n (%) 16 (30) 42 (43) 12–14 = 4 very good, n (%) 9 (17) 15 (16)

Results of variance analysis and ordinal regression for assessment of differences between the work schedule groups in frequency of food consumption and in DSI and RI (controlling for covariates sex and age). The descriptive values include mean value (mean) and standard deviation (SD) as well as absolute and relative frequencies. 2 Test statistic for the variance analysis is Fisher’s F. Partial Eta square ()η partial was used as the measure of effect size. Test statistic for ordinal regression is the Wald statistic (W). Positive estimators in ordinal regression suggest that in comparison to AS, employment in RS is associated with a higher category of the dependent variable. Negative estimators mean that in comparison to AS, employment in RS is associated with a lower category for the dependent variable. Confidence interval (CI) is defined by the lowest (L) and the highest (H) values. aCriteria for the aggregated assessment of the food choices were developed by Korinth and Schieß [27]. For the present study, this scoring was used with adjusted food category identifiers and with previously marked modifications. R. SEIBT ET AL.: NUTRITION AND HEALTH IN HOTEL STAFF 481

Table 3. Regularity of eating by shift group

Regularity AS (n = 53) RS (n = 97) Estimator W values P values 95% CI

L H

Breakfast Never, n (%) 12 (23) 11 (11) 0.457 1.782 NS −0.214 1.127 1–2 times per week, n (%) 8 (15) 20 (21) >2 times per week, n (%) 9 (17) 8 (8) Every day, n (%) 24 (45) 58 (60) Lunch Never, n (%) 1 (2) 7 (7) 0.158 0.205 NS −0.527 0.843 1–2 times per week, n (%) 6 (11) 7 (7) Downloaded from >2 times per week, n (%) 15 (28) 24 (25) Every day, n (%) 31 (59) 59 (61) Dinner Never, n (%) 0 (0) 1 (1) 0.321 0.824 NS −0.372 1.013 1–2 times per week, n (%) 7 (13) 6 (6)

>2 times per week, n (%) 16 (30) 27 (28) http://occmed.oxfordjournals.org/ Every day, n (%) 30 (57) 63 (65) Between meals Never, n (%) 6 (11) 8 (8) −0.518 2.525 NS −1.158 0.121 1–2 times per week, n (%) 11 (21) 33 (34) >2 times per week, n (%) 10 (19) 26 (27) Every day, n (%) 26 (49) 30 (31)

Results of ordinal regression for assessment of differences in regularity of meals and snacks between the work schedule groups (controlling for sex and age). The descriptive values include absolute and relative frequencies (number (%)). Test statistic for regression is the Wald statistic (W). Positive estimators in ordinal regression suggest that in comparison to AS, employment in RS is associated with a higher category of the dependent variable. Negative estimators mean that in comparison to

AS, employment in RS is associated with a lower category for the dependent variable. Confidence interval (CI) is defined by the lowest (L) and the highest (H) values. at University of California, Santa Barbara on August 23, 2015 level. Women showed significantly lower triglyceride and hotel employees working AS and RS. However, AS LDL cholesterol values, a lower LDL:HDL ratio and higher employees had on average lower fat mass and higher HDL cholesterol values than men. Total cholesterol and active cell mass but reported more pronounced health LDL cholesterol increased with age. complaints. Health complaints differed considerably between The comprehensive data make it possible to ana- shift groups. Compared with the RS, employees with AS lyse in detail the possible negative health effects of reported on average more health complaints and these shift work and to evaluate the nutritional and health were more serious (AS: 12 ± 9; RS: 10 ± 7; P < 0.05). The characteristics of hotel industry employees, so far a most frequent complaints (Beschwerden-Liste, B-L) rarely studied occupational group. Moreover, critical [26] for both groups were an excessive sleep requirement health parameters (i.e. body size, body composition (AS: 15%; RS: 7%), anxiety (AS: 13%; RS: 8%), irrita- and metabolic parameters) were measured objectively, bility (AS: 8%; RS: 5%) and exhaustion (AS: 6%; RS: thereby avoiding subjective response bias. In addition, 4%). There were no significant differences in the number two important factors (sex and age) were statistically of medical diagnoses (Work Ability Index, subscale WAI controlled. 3, short version) [25] between the groups. The most fre- The ex post facto cross-sectional nature of the study quently mentioned diagnoses were musculoskeletal dis- is a substantial methodical limitation. A targeted orders (AS: 19%; RS: 18%) and cardiovascular disease manipulation of the independent variable (shift sys- (AS: 11%; WS: 12%). Employees with AS also reported tem) was not possible for ethical and practical reasons. a high number of accidental injuries (AS: 28%; RS: 9%). A healthy worker effect may also influence the results. In comparison to women, men suffered significantly Accordingly, current shift workers would appear to less from nausea, hypersensitivity to cold, an excessive be healthier than expected. Thus, the associations sleep requirement and dizziness. Excessive sleep require- between shift work and health-related variables remain ment decreased significantly with age. unclear. Furthermore, the surveyed group was a convenience Discussion sample and participation was voluntary. There is rea- son to believe that voluntary participants differ from This study found no differences in nutritional behav- involuntary participants. Health-conscious employees iour, body dimensions or metabolic parameters between or employees with more free time may be more likely 482 OCCUPATIONAL MEDICINE

Table 4. Health parameters by shift group

2 AS (n = 53) RS (n = 97) Test statistic P values η partial OR 95% CI

LH

Body measurements BMI (kg/m2), mean ± SD 24.3 ± 3.4 24.8 ± 4.3 F = 2.406 NS 0.016 Overweight (BMI ≥ 25.0–29.9), n (%) 15 (28) 32 (33) W = 2.959 NS 0.635 −0.089 0.359 Obese (BMI ≥ 30.0), n (%) 4 (8) 10 (10) Waist circumference (cm), mean ± SD 85.2 ± 12.2 83.6 ± 13.7 F = 0.925 NS 0.006 Increased health risk (men > 94; 12 (23) 23 (24) W = 1.139 NS 0.390 −0.326 1.106 women > 80), n (%) Markedly increased health risk 6 (11) 15 (16) (men > 102; women > 88), n (%) Downloaded from WHR, mean ± SD 0.8 ± 0.1 0.8 ± 0.1 F = 0.380 NS 0.003 Increased health risk (men > 1.0; 5 (9) 14 (14) W = 0.557 NS B: −0.423 0.655 0.215 1.991 women > 0.85), n (%) Proportion of fat mass (%), mean ± SD 25.9 ± 7.1 30.3 ± 8.7 F = 3.686 <0.05 0.025 a

High , n (%) 15 (28) 24 (25) W = 1.699 NS 0.446 −0.225 1.117 http://occmed.oxfordjournals.org/ Very higha, n (%) 11 (21) 23 (24) Proportion of active cell mass 42.4 ± 8.6 38.2 ± 6.0 F = 6.754 <0.01 0.045 (%), mean ± SD Metabolic parameters Glucose (mg/dl), mean ± SD 84.1 ± 12.5 86.1 ± 10.0 F = 1.155 NS 0.009 Guidance level: 55–100, n (%) 42 (89) 77 (92) W = 0.127 NS B: 0.228 1.256 0.358 4.414 Critical level: >100, n (%) 5 (11) 7 (8) Triglycerides (mg/dl), mean ± SD 141.8 ± 94.4 135.1 ± 108.0 F = 0.211 NS 0.002 Guidance level: <200, n (%) 36 (77) 73 (87) W = 0.647 NS B: 0.406 1.501 0.558 4.038 Critical level: >200, n (%) 11 (23) 11 (13) at University of California, Santa Barbara on August 23, 2015 Total cholesterol (mg/dl), mean ± SD 200.0 ± 36.2 200.0 ± 37.7 F = 0.022 NS 0.000 Guidance level: <200, n (%) 23 (49) 50 (60) W = 0.965 NS B: 0.387 1.472 0.681 3.182 Critical level: >200, n (%) 24 (51) 34 (41) LDL cholesterol (mg/dl), mean ± SD 112.9 ± 30.3 109.3 ± 35.5 F = 0.030 NS 0.000 Guidance level: <160, n (%) 45 (96) 77 (92) W = 1.703 NS B: −1.167 0.311 0.054 1.796 Critical level: >160, n (%) 2 (4) 7 (8) HDL cholesterol (mg/dl), mean ± SD 59.9 ± 18.1 66.2 ± 18.8 F = 0.097 NS 0.001 Guidance level: >40, n (%) 7 (15) 6 (7) W = 0.248 NS B: 0.313 1.368 0.399 4.695 Critical level: <40 40 (85) 78 (93) LDL:HDL ratio, mean ± SD 2.1 ± 0.9 1.9 ± 1.0 F = 0.009 NS 0.000 Guidance level: <3, n (%) 42 (89) 73 (87) W = 1.034 NS B: −0.631 0.532 0.158 1.795 Critical level: >3, n (%) 5 (11) 11 (13) Diseases and health complaints Medical diagnoses (number) Mean ± SD 1.1 ± 1.2 0.9 ± 1.2 F = 1.324 <0.01 0.009

M (Q25; Q75) 1 (0; 2) 0 (0; 2) U: 2288.5 NS Complaintsb (value range: 0–60), 12.2 ± 9.1 9.7 ± 7.4 F = 4.122 <0.05 0.028 mean ± SD

Results of variance analyses, ordinal regression and logistic regression for assessment of differences in health parameters between the groups (controlling for sex and age). The descriptive values include mean value (mean) and standard deviation (SD), absolute and relative frequencies (number (%)) as well as median (M) and the 2 25th (Q25) and 75th (Q75) percentiles. Test statistic for the variance analysis is Fisher’s F. Partial Eta square ()η partial was used as the measure of effect size. Test statistic for ordinal regression is the Wald statistic (W). Positive estimators in ordinal regression suggest that in comparison to AS, employment in RS is associated with a higher category of the dependent variable. Negative estimators mean that in comparison to AS, employment in RS is associated with a lower category of the dependent variable. The measure odds ratio (OR) in logistic regression shows the factor by which the chance of belonging to the health-endangering level of the dichotomous criteria rises (the level ‘RS’ acts as reference category). Confidence interval (CI) is defined by the lowest (L) and the highest (H) values. B, regression coefficient of the logistic regression; U, Mann–Whitney U-test. aClassification according to Gallagher et al. [28]. bRaw values of the B-LR: 0 (complete lack of symptoms) to 60 (considerable impairment across all surveyed complaints). to take advantage of occupational health screening. free time may suggest lower workload and a lower Both factors could influence the target variable, since stress level. a health-conscious attitude is very likely to be associ- In the literature reviewed, two studies indicated that ated with healthier nutritional behaviour and additional shift workers eat less regularly and less frequently than R. SEIBT ET AL.: NUTRITION AND HEALTH IN HOTEL STAFF 483 day workers [15,16]. Duchon and Keran [15] found that industry do tasks that are physically more demanding the proportion of those who had three meals per day (e.g. housekeeping and warehouse management) than declined from 28% for the day shift to 19% for the even- the tasks of the RS workers (e.g. accounting and recep- ing shift to 6% for the night shift. Furthermore, 9% of tion). As a result of these demanding activities, muscle survey participants in the day shift, 11% in the evening mass (a component of active cell mass) is built up and shift and 25% in the night shift had only one meal per fat mass is reduced. This effect should be further studied day. These differences in the regularity of meals between in follow-up research. AS and RS workers were not demonstrated in our study. The finding that AS workers had more serious health However, neither of the groups achieved the consump- complaints is in accordance with the literature [5–8]. tion of five servings of fruit and vegetables per day, as However, the expected typical differences in the fre- recommended by the German Association for Nutrition quency of cardiovascular and gastrointestinal diseases [29], and moreover, a relatively frequent consumption of [6,7] were absent. This could be a result of the young

sweets was observed. age of sample or the healthy worker effect. However, Downloaded from Previous research also reported that shift workers shift work is generally much less associated with signifi- were often dependent on their own cold meals as a result cant diseases than minor health complaints [5]. To sum- of insufficient workplace catering services and a lack of marize, this study provides important pointers to the availability of unprocessed foodstuffs [15,17,30], and nutrition and health of shift workers in the hospitality

such meals may be nutritionally unbalanced, high in industry. These findings are relevant for the develop- http://occmed.oxfordjournals.org/ calories and difficult to digest. Additionally shift work- ment of appropriate illness prevention and intervention ers often have a low intake of dietary fibre, low liquid programmes. intake, high share of saturated fats and simple/isolated carbohydrates and low consumption of starch and slow Key points carbohydrates [17]. In this study, we did not measure the exact calorie intake and the nutritional composition ••Nutritional problems typically associated with shift of consumed food, but the nutritional intake did not work were largely absent in this study of - differ significantly between AS and RS workers. In this ity industry workers. The nutritional behaviour of the employees studied, working in alternating and respect, the results are in agreement with the literature at University of California, Santa Barbara on August 23, 2015 [31]. regular shifts, did not differ from each other and Nutritional problems associated with shift work in could be considered moderately healthy to good. other industries seem to have little or no significance in ••Between the shift groups, there were no signifi- the hotel industry. Providing food to customers can result cant differences in body dimensions or metabolic in heightened attention to one’s own nutrition. Because parameters. In comparison to the regular shift nutritional behaviour was self-reported, it is possible that workers, those working alternating shifts had lower the AS workers represented their eating habits in a more fat mass and higher active cell mass but reported favourable light than in reality, over-reporting consump- more, or more pronounced, health complaints. tion of healthy foodstuffs or under-reporting that of less ••The significant influence of sex and age on nutri- healthy foodstuffs. tional behaviour was confirmed. A considerable gap exists in the definition of ‘alternat- ing shifts’ between the existing literature and this study. While several studies deal predominantly with shift work Funding in shift systems with night work, this study concen- Government Safety Organization Foods and Restaurants in trates on shift workers with alternating day and evening Mannheim (BGN). shifts, where the evening shift lasted until 1 or 2 a.m. Consequently, the AS might have been a milder stress factor, due to the lack of a full night shift. Conflicts of interest Our results did not find the often reported abnormal None declared. body dimensions [9,11,13] and poor metabolic values [13,14,22] of shift workers in comparison to day work- ers. Considering the nutritional behaviour of both groups References was similar, these results are not surprising. A surprising 1. Nahrung-Genuss-Gaststätten (NGG). Branchenreport finding was the lower fat mass and higher active cell mass Hotel- und Gaststättengewerbe in Deutschland. Hamburg: for shift workers. So far there has been no research on NGG, 2008. the body composition of shift workers. However, a con- 2. Lohmann-Haislah A. Stressreport Deutschland 2012. sensus exists among researchers that the typical weight Psychische Anforderungen, Ressourcen und Befinden. gain of shift workers can be attributed to an increase in Dortmund: Bundesanstalt für Arbeitsschutz und body fat mass [21]. However, AS workers in the hotel Arbeitsmedizin, 2012. 484 OCCUPATIONAL MEDICINE

3. European Foundation for the Improvement of Living and diet situation at shift-work]. Ernährung—Wissenschaft und Working Conditions. EU Hotel and Restaurant Sector: Praxis 2007;1:454–461. Work and Employment Conditions. Luxembourg: Office 18. Antunes LC, Levandovski R, Dantas G, Caumo W, Hidalgo for Official Publications of the European Communities, MP. Obesity and shift work: chronobiological aspects. Nutr 2004. Res Rev 2010;23:155–168. 4. Maack K, Haves J, Homann B, Schmid K, Hadwiger F. 19. Uetani M, Sakata K, Oishi M et al. The influence of Die Zukunft des Gastgewerbes – Beschäftigungsperspektiven im being overweight on the relationship between shift work deutschen Gastgewerbe. Düsseldorf: Hans-Böckler-Stiftung, and increased total cholesterol level. Ann Epidemiol 2013. 2011;21:327–335. 5. Angerer P, Petru R. Schichtarbeit in der modernen 20. Ghiasvand M, Heshmat R, Golpira R et al. Shift working Industriegesellschaft und gesundheitliche Folgen. and risk of lipid disorders: a cross-sectional study. Lipids Somnologie—Schlafforschung und Schlafmedizin 2010;2: Health Dis 2006;5:9. 88–97. 21. Novotny R, Chen C, Williams AE, Albright CL, Nigg CR, 6. Tucker P, Knowles SR. Review of studies that have Oshiro CE. US acculturation is associated with health Downloaded from used the Standard Shiftwork Index: evidence for the behaviours and obesity, but not their change, with a hotel- underlying model of shiftwork and health. Appl Ergon based intervention among Asian-Pacific Islanders. J Acad 2008;39:550–564. Nutr Diet 2012;112:649–656. 7. Wang X, Armstrong M, Cairns B, Key T, Travis R. Shift 22. Kalua EA, Nicolaisen NM, Reza A, Morrison LA, Brown work and chronic disease: the epidemiological evidence. DE. Sex differences in the relation between body size

Occup Med (Lond) 2011;61:78–89. and composition to ambulatory blood pressure vari- http://occmed.oxfordjournals.org/ 8. Szosland D. Shift work and metabolic syndrome, diabe- ability among hotel workers in Hawaii. Am J Hum Biol tes mellitus and ischaemic heart disease. Int J Occup Med 2005;17:245–246. Environ Health 2010;23:287–291. 23. Bohle P, Quinlan M, Kennedy D, Williamson A. 9. Frost P, Kolstad HA, Bonde JP. Shift work and the risk Working hours, work-life conflict and health in pre- of ischemic heart disease—a systematic review of the carious and ‘permanent’ employment. Rev Saúde Públ epidemiologic evidence. Scand J Work Environ Health 2004;38:19–25. 2009;35:163–179. 24. Westenhöfer J. Kurztest zur Verzehrhäufigkeit von 10. Knutsson A, Bøggild H. Gastrointestinal disorders among Lebensmitteln. Stern 2003;12:207–209. shift workers. Scand J Work Environ Health 2010;36:85–95. 25. Hasselhorn HM, Freude G. Der Work Ability Index—ein 11. Paridon H, Ernst S, Harth V et al. Schichtarbeit—Rechtslage, Leitfaden. Dortmund: Bundesanstalt für Arbeitsschutz und at University of California, Santa Barbara on August 23, 2015 gesundheitliche Risiken und Präventionsmöglichkeiten. Arbeitsmedizin, 2007. DGUV Report 1/2012. Berlin: Deutsche Gesetzliche 26. Von Zerssen D, Petermann F. Beschwerden-Liste (B-LR, Unfallversicherung, 2012. Revidierte Fassung). Manual. Göttingen: Hogrefe, 2011. 12. Bara AC, Arber S. Working shifts and —find- 27. Korinth A, Schieß S. Empirische Untersuchung zur ings from the British Household Panel Survey (1995– Änderung des Ess- und Ernährungsverhaltens von 2005). Scand J Work Environ Health 2009;35:361–367. Ökotrophologen und Ernährungswissenschaftlern im 13. Kim HI, Jung S-A, Choi JY et al. Impact of shift work Verlauf des Studiums. Dissertation, HAW Hochschule für on irritable bowel syndrome and functional dyspepsia. J angewandte Wissenschaften, Department Ökotrophologie, Korean Med Sci 2013;28:431–437. 2006. 14. Selvi Y, Özdemir P, Özdemir O, Aydin A, Beşiroğlu L. 28. Gallagher D, Heymsfield SB, Heo M, Jebb SA, Influence of night shift work on psychologic state and Murgatroyd PR, Sakamoto Y. Healthy percentage quality of life in health workers. J Neurosci body fat ranges: an approach for developing guidelines 2010;23:238–243. based on body mass index. Am J Clin Nutr 2000;72: 15. Duchon JC, Keran CM. Relationships among shiftworker 694–701. eating habits, eating satisfaction, and self-reported health 29. Deutsche Gesellschaft für Ernährung e. V. (DGE). in a population of US miners. Work Stress 1990;4:111–120. Vollwertig essen und trinken nach den 10 Regeln der DGE 16. Lasfargues G, Vol S, Cacès E, Le Clésiau H, Lecomte P, [internet], 2013. http://www.dge.de/pdf/10-Regeln-der- Tichet J. Relations among night work, dietary habits, DGE.pdf (20 February 2014, date last accessed). biological measure, and health status. Int J Behav Med 30. Stewart AJ, Wahlqvist ML. Effect of shiftwork on canteen 1996;3:123–134. food purchase. Occup Med (Lond) 1985;27:552–554. 17. Petschelt J, Behr-Völtzer C, Rademacher C. Was essen, wenn 31. Suwazono Y, Dochi M, Sakata K et al. A longitudinal study andere schlafen? Gesundheits- und Ernährungssituation on the effect of shift work on weight gain in male Japanese bei Schichtarbeit [Eating what if others sleep? Health and workers. Obesity 2008;16:1887–1893.