Analysis On The Bias Of Estimation Of Dietary Intake Of Residents By Improvement Of Cholesterol Measurement Technology

BackgroundCholesterol is a perhydrocyclopentanophenanthrene derivative. Choleste rol in the body has a wide range of physiological functions, but whe n it is excessive, it will lead to high cholesterol, produce adverse eff ect to the body. Modern studies have found that there is a close corr elation between venous thrombosis, atherosclerosis, gallstone disease a nd high cholesterol.Therefore, how to control cholesterol intake to red uce the incidence of chronic diseases such as obesity, cardiovascular and cancer has become a hot issue in the field of nutrition. At prese nt, the recommended cholesterol intake is generally not more than 30 Omg/d. The evaluation of dietary cholesterol intake in the population by using cholesterol data in the food composition table. At present, China’s food composition table of cholesterol composition of food cat egories in the data is obtained by GB/T5009.128-2003 colorimetry Sp ectrophotometry. With the development of chromatography detection methods, in recent years, the application of gas phase, liquid phase d etection methods have also been introduced, GBT22220-2008 (liquid chromatography) in the detection of food cholesterol in our country i s widely used. The differences detection methods of cholesterol comp osition of different foods may lead to differences in the evaluation of dietary cholesterol intake.ObjectiveBy comparing method to determine the optimal detection method for the determination of cholesterol, and to assess the cholesterol determi nation of technical improvement of the dietary intake estimates of bia s.Research method1. improved methods for determination of cholesterol Established UPLC method for determination of cholesterol and UPLC method and GB/T5009.128-2003 points spectrophotometric method of pretreatment conditions and testing conditions for 2 x 2 analysis by e xperiments. According to the method of science compare method req uires the precision, accuracy and sensitivity, the improved method for determination of cholesterol, different pretreatment conditions and dete ction conditions of different matrix food (meat, eggs, milk) influence the test results analysis for analysis. In the Beijing market acquisitio n of cholesterol rich foods (meat, eggs and milk), the detection is ca rried out according to the method of 1 to determine the orthogonal e xperimental method and statistical analysis of the data, the analysis o f pretreatment and detection conditions to detect the influence.the ana lysis of the difference of the results of different matrix foods.The im proved methods of cholesterol determination and spectrophotometry w ere used to detect the difference of meat, egg and milk samples.2. Determination of food categories for food component data. Detection of meat, eggs, milk samples, detection results and the 2002 version of the food composition table of the relevant food categorie s cholesterol composition data comparison, statistical analysis of differ ences.3. Analysis of the bias in the estimation of dietary intake of resident s by the improvement of the cholesterol determination technique. Respectively by spectrophotometry and cholesterol determination meth od to improve new measurement of meat, eggs, milk samples cholest erol content data instead of the original tables of food composition d ata, calculation of cholesterol intake by using different data source li brary. The results of statistical analysis of the differences.4. statistical methodsUsing Excel 2013 to edit the data, using SPSS 19.0 to establish the d atabase and statistical analysis. Normal distribution data using mean a nd standard deviation, t test and analysis of variance was performed for comparison between groups, non normal distribution data, using t he median (four digits-consists of four digits) formal description, gr oup compared with rank sum test. Difference test standard:P<0.05 h ad statistical significance.Results1. Cholesterol major dietary sources of food categories:2011-2012 Be ijing dietary cholesterol is the main source of food categories in orde r to 69.9% of eggs and meat 25.7%, dairy 2.79%.2. The best test condition for UPLC method:a spectrophotometric co lorimetry method parameters:the linear range of the method 9.0ug/m L-35ug/mL, linear equations for y=0.0037x+0.0440 R=0.9997, quantita tive methods limit 11.2mg/100g. Sample in three levels of cholesterol in the average recovery rate was 85.8%,84%,89.7%, egg yolk sam pies at three levels of cholesterol, the average recovery rate was 10 1%,107%,117%, milk powder samples in three levels of cholesterol in the average recovery rate was 96.3%,111%,114%, meat, eggs, milk and cholesterol in RSD were 5.35%,7.11%,6.69%; b.UPLC m ethod parameters:a linear range of 10.0-300 g/mL, linear equation y = 3.34×103x-5.63×103,, R=0.9999, the limit of quantity 3.50 mg/100g, sample cholesterol in three levels in the average recovery r ate was 90.8%,89.3%,90.7%, egg yolk samples in the three levels of cholesterol, the average recovery rate was 95.4%,97.8%,98.8%, milk powder samples in three levels of cholesterol in the average rec overy rate was 89.8%,92.2%,95.5%; meat, eggs, milk cholesterol in RSD were 2.74%,3.68%,3.25%3. UPLC method and original points spectrophotometric method in th e detection of meat and milk, results no significant difference (P> 0. 05). In eggs food detection results are significant difference (P< 0.0 5).4. Cholesterol major dietary sources of food the spectrophotometric c olorimetry to detect and raw food composition table food related cate gory data statistical analysis and egg cholesterol food composition oc curred change (P< 0.05), and meat and milk cholesterol content did not occur change (P> 0.05).5. Improved UPLC method for detection technology for the bias of t he residents dietary cholesterol intake assessment is the existence of data increased 16.6%(P< 0.05), food (eggs) cholesterol levels reduc es the 12.0%(P< 0.05). It is very necessary to develop a regular m onitoring of food composition and to assess the data bias in the anal ysis technique.Conclusion1. UPLC method and spectrophotometry in eggs food detection result s are statistically significant difference (P< 0.05), UPLC method was used to detect the result is higher than the spectrophotometric methd.2. Egg food food composition occurred change (P< 0.05) and spectr ophotometric method was used to detect the data below the 2002 ver sion of the food composition table eggs of food related data.3. The improvement of cholesterol measurement technique is the UPL C method to estimate the dietary intake of residents. The results are compared with the method of spectrophotometry. The results of the e stimation of dietary intake of residents are 16.6%.