Dietary Structure And Vitamin A Status Of The Long-haul Truck Drivers

BackgroudTruck drivers are exposed to a variety of stressful situations,such as working long hours,sleep deprivation,inadequate rest and relaxation,being away from home and support systems,and driving in hazardous conditions.Also because of long night working maybe need more vitamin A.However,up to date there has few papers regarding the health status of truck drivers in domestic,and most of these papers were limited in investigating several definite infection diseases,such as HBV HIV infectious rate.Meanwhile there were plenty of research papers in abroad concerning the high incidence rate of chronic disease and several cancers,such as obesity,coronary artery disease,diabetes mellitus, lung cancer,colorectal cancer,and these papers which uniformly considered that long-haul truck drivers were at risk for poor health outcomes.The prevalence rates of working factors affecting health problems of truck drivers were significantly higher than the general population in the items on irregular shift work,working environment,working posture, handling heavy materials,job stress due to overloading and long working time and limited time off.One paper suggested that Drivers who placed greater importance on healthful food choices had more positive attitudes about restaurants'provision of such options,they wanted more healthful options.Researches also indicated that long-haul truck drivers were very concerned with taste.Diet and nutrition are important factors in the promotion and maintenance of good health throughout the entire life course.Their role as determinants of chronic NCDs is well established.However,up to date,there were none published papers concerning the food consumption and nutrients intake of long-haul truck drivers,none with the vitamin A status which makes key point in the dark adaptation of long-haul truck drivers.This study is conducting a dietary survey to investigate the food consumption and nutrients intake,food choice habit,nutritional and health knowledge in long-haul truck drivers.ObjectiveThe objective of the study was to investigate the dietary patterns,food consumption and nutrient intake of the long-haul truck drivers:evaluated vitamin A status of the long-haul truck drivers;explore the exist problems in the long-haul truck drivers" daily diet.Subjects and methods1.Research objectsSubjects(n=145) were long-haul truck drivers,aged 18-55years,came from three big freight yards in Shanghai and Nan tong(a big harbor city of Jiangsu province).2.Dietary survey methods2.1 24h recall dietary surveyThree days 24-hour food recalls were conducted in two working days and a resting day,which assist by plenty of food models(as a present from Shanghai GongRong food model Manufacture Company).Food intakes were adjusted for age,sex and physical activity to yield standardized estimates per 'reference man',defined as an adult male,19-59 years of age,65 kg body weight,undertaking very light physical work.Average daily nutrient intakes were calculated on the basis of Chinese food composition Tables(Institute of Health,2002) and expressed per reference man.2.2 Food frequency questionnaireA food frequency questionnaire with vitamin A(includingβ-carotene)-containing foods was conducted.Several preliminary experiments were undertaken before the formal experiment.3.Biochemistry index detection3.1 Serum retinolFasting blood samples were obtained from 128 healthy long-haul truck drivers. Fasting intravenous blood(5 ml) was drawn from each subject between 08.00 hours and 12.00 hours,using negative pressure vacuum pipe(10ml).Samples were immediately placed on ice in light-free jars and then transported to the laboratory(within 4 h of the last blood sample).On arrival at the laboratory the blood samples were immediately divided into fractions and stored at -80o.Serum level of retinol was determined by the HPLC method.3.2 Serum lipoidsSerum total cholesterol(TC) level was determined by CHOD-PAP method;Serum triglyceride(TG) was determined by GPO-PAP method;high density lipoprotein cholesterol(HDL-C) level was determined by elimination method. Hypercholesteremia(TC≥5.72mmol/L):total cholesterol borderline heighten (TC5.20-5.71mmol/L);hypertriglyceridemia(TG≥1.70mmol/L);Low HDL-C (HDL-C≤0.91mmol/L).Dyslipidemia resulted in one of hypercholesteremia, hypertriglyceridemia,Low HDL-C.3.3 Overweight and obesityAll subjects were asked to worn only light clothes and with barefoot before stand in the health meter.Body mass index(BMI) criterion standard:<18.5(underweight); 18.5-23.9(normal);24-27.9(overweight);≥28(obese).4.Dark adaptometryYA-2 dark adaptometry was used in Dark adaptation detection.The range of normal values of the equipment was pre-performed by healthy control subjects.Steps of the detection:five minutes of pre-adaptation→two minutes of highlight exposure→identify the direction of the marker→record the time by the equipment runner.5.Data statistical analysisAll data entered by two staffs,and check out by another staff in the end.Descriptive statistics including means,medians,standard deviations and ranges of average values were computed for all relevant biochemical indicators of dietary intakes of nutrients,foods and frequencies of intake of selected foods,and vitamin A status.All the data were analyzed using the SPSS 11.0 statistical software package.Results1.Sample featureThere were 145 long-haul truck drivers completed the dietary survey.143 were male and 2 were female.Mean age and occupational age of these long-haul truck drivers was 35y and 5.5y,respectively.408 days of dietary records were conducted.Based on BMI measurements for 145 subjects,one was underweight;75 were normal;69 were overweight;of these,25 were obese.Serum lipoids level was detected in 128 blood sample. The prevalence rates of hypertriglyceridemia.hypercholesteremia,low serum high density lipoprotein cholesterol,total cholesterol marginal increase or hyperlipemia were 60.2%, 1.6%,40.6%,7.8%,68.0%,respectively.2.Food consumption and nutrients resourceDietary patterns between working days and resting days were quite different.Both food consumption and nutrients intake showed great gap between working days and resting days.In working days,neither macro-nutrients nor micro-nutrients intake were sufficient, according to the Recommended Nutrient Intake(RNI).Extremely low food consumption contribute to the results discussed above.In working days,protein,fat and carbohydrate intake per person per day was 40.7,39.4 and 134.5g,respectively.Energy intake was 1161kcal per person per day.Intake of all kinds of vitamins(except vitamin E) and mineral (except sodium) were low in compare to the RNI.However,in resting days,most nutrients intake were sufficient,though,because of the high consumption of meat and meat products, Poultry and poultry products and edible oil,protein(118.5g,15.0%energy intake) and fat (132.6g,37.7%energy intake) intake were too high,energy intake was 3177kcal per person per day(132.4%RNI),meanwhile,carbohydrate intake(307.2g,38.9%energy intake) was low in compare to the Chinese dietary guideline,which recommended that diet carbohydrate should contribute to 55-65%total energy intake.On the other hand,low consumption level of vegeTables and fruits,milk and dairy products,Tubers,starches and products,were associated with low intake level of vitamin A and calcium.3.Vitamin A intake and serum retinol levelThe average retinol equivalent intake in per day was 329.7μg for per reference man. The drivers with the retinol equivalent intake equal or higher than RNI accounted for 15% and those with the intake lower than 50%of the RNI accounted for 50%.Vitamin A intake was quite different between working days and resting days.The average retinol equivalent intake in per day was 252.6μg for per reference man in working days compared to 602.3μg in resting days,accounted for 31.5%and 75.2%of the RNI.Serum retinol was detected in 115 blood sample.The average serum retinol concentration was 2.04μmol/l.The prevalence rates of serum retinol <0.70μmol/L,<1.05μmol/L and 1.40μmol/L were 0.9%(N=1),3.5 %(N=4),8.7%(N=11),respectively.4.Dark adaptation time41 subjects were conducted dark adaptation detection.The mean dark adaptation time was 31±14s,which 14(34%) drivers over 30s,3(7%) drivers over 60s.Discussion and suggestionThere were wide gaps in the dietary patterns between working days and resting days. Both food consumption and nutrients intake showed great different between working days and resting days.In working days,neither macro-nutrients nor micro-nutrients intake were sufficient.In resting days,because of the high consumption of Meat and meat products. Poultry and poultry products and edible oil,energy,protein and fat intake were too high; meanwhile,carbohydrate intake was lower in compare to the Chinese dietary guideline.On the other hand,low consumption level of vegeTables/fruits,milk and dairy products. Tubers,starches and products,were associated with low intake of several vitamins and minerals such as vitamin A and calcium.A new battle has begun to ensure the health and nutrition of Long-haul truck drivers. It is vital that government develop new effective policies and educational strategies together with many nutritional promotions by those public organizations to deal with these challenges.On one hand,raise the meals quality in the truck-stop restaurant.Drivers want to improve health,but not if it means a reduction in palatability.On the other hand,the long-haul truck drivers could be taught to make a better choice in choosing foods,such as, eat more natural vegetality foods not these deep processing products.Conclusions1.While obesity and dyslipidemia continues to increase among the general population in China,for long-haul drivers these problem are much more severe.Nearly one third of drivers in this study are overweight,over two thirds of drivers are dyslipidemia.2.There were severe problems resided in the long-haul truck drivers' daily diet.In working days,the extremely low food consumption leads to wide-bound nutrients intake inadequacy, while in resting days,the Long-haul truck drivers group has developed dietary patterns that include excessive energy intake and a high intake of saturated fatty acids and cholesterol together with insufficient levels of vitamins,minerals,and dietary fiber.3.The consumption frequency of foods containing plentiful retinol or vitamin A precursors was extremely low.Insufficient intake of Vitamin A was widespread in long-haul truck drivers,which may affect the darkness visual acuity of the long-haul drivers when working in the dark environment.