| Considering the Tibet plateau located at a critical position,regular garrison at those positions is necessary.Compared with plain,the environment of plateau is of several primary hazardous factors such as low pressure,low oxygen concentration,low humidity,cold and strong sun radiation.Due to the fact that constant armed forces are stationed,special health service at high altitude is strongly required.Diet on plateau is a key point in daily health care.Proper diet can keep fit for soldiers and plays critical roles in the maintenance of battle effectiveness.The existing“Dietary allowances for military personnel”stipulates higher intake of energy content in plain daily diet,while specialized allowances standard for plateau is still absent because of the lack of nutritional data.Aim to satisfy the physiological needs at high altitude such as dehydration,high BMR and hypoxia,diets on high altitude should have its unique characters,including more mineral and soluble vitamins proportion.Thus,making a custom protocol of high-altitude diet is pressing and essential for high-altitude medical service.Purpose:we made a cross-sectional investigation to characterize and evaluate the status of diet service on high altitude.The results can underlie the theoretical basis of service improvement and specific functional food development on high-altitude.Content:1.We consulted related literature review to investigate the characteristics of high-altitude environment and its effect on appetite,gastrointestinal digestion,the absorption and metabolism of nutrients,body composition,cognition function and exercise ability.2.Using cross-sectional study to investigate four high altitude troops?Troop A and D,low labor intensity;Troop B,moderate labor intensity;Troop C,heavey labor intensity?at plateau area.?1?Dietary nutrition investigation.Evaluating the intakes of nutrients by using food weight method.Examining body weight and ingredients by electrical bioimpedance test.Measuring blood albumin and lipid level via blood biochemistry test.Using ELISA to test vitamin levels and flame atomic absorption spectrometry to test mineral materials content.?2?General physical condition investigation.Using questionnaires to investigate the morbidity of chronic high-altitude disease.Using cyanmethemoglobin determination method to test Hb content and evaluate the morbidity of high altitude polycythemia?HAPC?.Measuring others indices including HR,BP,SaO2,CK,LDH,AST,ALT,?-GT,Cr,etc.?3?Using computerized neurobehavioral evaluation and step experiment to understand the soldiers'congnitive function.3.Evaluating the protective effect of complex vitamin B families and fish oil in a model of hypoxic rat.4.Using literature research,interview survey and questionnaire to investigate the mainly affective factors on the diet service of high-altitude forces.5.On the basis of literature review,field investigation,experimental research and expert questionnaire survey,put forward proposing possible improvements aiming at the problems in the dietary and nutrition service of troops stationed at high altitude.Result:1.Field investigation?1?The dietary structure of the plateau soldiers was irrational and the current dietary nutrition service had not fully met the demand of nutrients requirement in hypoxia environment.?1?Food intakes:the intakes of eggs,milk,plant oil of troop A and troop B met the requirement of military standard,but the rest did not.The intakes of grain,meat,poultry,fish,beans,vegetables,dried vegetables,edible fungus,sugar and fruit in troop A were 39.9%46.2%,6.0%,24.0%,5.4%,26.7%,13.5%,0%,1.3%and 20.0%of that in standard respectively,troop B were 87.6%,56.1%,30.2%,13.5%,24.0%,68.5%,3.0%,20.0%,16.7%and 16.0%.?2?The proportion of fat in diet was relatively higher because of much plant oil intake.The intake of high-quality proteins was well supplied due to plenty meat,eggs and milk service.The intakes of potassium,zinc and magnesium,VD,VC,VB1,VB2 of troop A were deficient,and the VA,VB6,folic acid and VB12 were insufficient,the rest of nutrients were sufficient.For troop B,VB2,calcium,iodine,VA,VD,VB6,folic acid and VB12 were insufficient,the rest of nutrients were sufficient.?3?Physical index:BMI and upper arm musle circumference in investigated troops were normal,and the percentage of body fat was low.?4?Serum protein,lipid and vitamin assays:high-altitude troops showed a high rate of dyslipidemia in HDL-C,however the HDL level in troop C was significantly higher than troop A and troop B.The standardized rates of VA,VD,VB1 and VB2 were 100%,1.4%,81.9%and 18.1%in the blood,respectively.The standardized rates of VB1 in troop C?100%?was significantly higher than troop A?15%?and troop B?59.5%?,The adequacy ratio of VB2?41.9%?was significantly higher than troop A?0%?and troop B?0%?.?5?Mineral assays:the adequacy ratio of zinc and iron in hair were low among high altitude soldiers.In addition,the adequacy ratio of magnesium of troop C?7.7%?was lowest among the four troops.The content of calcium,manganese and chromium was sufficient among high altitude soldiers.Appetite reduction is one of the most important reasons for insufficient intakes of nutrients,and the increase of nutrients in hypoxia environment has exacerbated the lack of nutrients in men.It is possible to maintain the military operation ability of soldiers by adjusting the cooking taste of meals,having diet and nutrition education and proper nutrition supplements.?2?According to questionnaire,the score of nutrition knowledge was moderate.The score of nutrition attitude was high.The score of nutrition behavior was moderate.High-altitude troops were lack of nutrition associated knowledge.Lack of nutrition knowledge would result in improper diet behaviors.Meanwhile,soldiers have strong aspiration to obtain nutritional related knowledge.Hence,it is necessary to strengthen the nutrition education.?3?Long term high altitude exposure impaired innervation system function,cognitive function and exercise ability.The morbidity of chronic high-altitude sickness was high.Multiple chronic high-altitude sickness induced by extreme environment have high morbidity including HAPC,plateau associated recession,sleep disorder,blood lipid disorder,myocardial enzyme impairment,etc.It was worth noting that high labor intensity exacerbates the morbidity of chronic high-altitude sickness.Although high labor intensity improved labor ability and kept soldiers athletic,the high altitude environment severely exacerbated the morbidity of HAPC and lipid metabolism malfunction.New special diet for this troop is required immediately.?4?Hypoxia in plateau impaired the work capacity and cognitive ability.This affected the effect of military mission.The work capacity of soldier decreased at plateau and they are easier to feel tired.The recover took much longer time in plateau than in plain.It is important to improve the dietary pattern to protect and improve those abilities2.Long term high altitude exposure impaired physical stamina and decreased maximum oxygen consumption rates.?1?Animal experiments showed that vitamin B complex and fish oil improved cognitive ability and some associated physic indices in animals exposed to hypobaric hypoxia.?2?The complex of sodium pyruvate/alanine showed protective effect in cell culture experiments.The 1:4-1:16 ratio of sodium pyruvate/alanine mixture exhibited synergistic effect in anti-hypoxia experiments of cells.The results indicated that enrichment of those nutrients may be protective to those who are stationed in high altitude for a long time.3.The main factors affecting the efficiency of high-altitude diet service included execution ability of protocols,application of high-altitude specific functional food,custom service protocol according to mission and labor intensity,receptive recipes of canteen,and effective education.4.In view of the problems existing in the dietary nutrition service of plateau troops,the suggestive strategies are recommended.?1?Strengthen the effectiveness of organizational management to ensure the implementation of the plan.?2?Improving the dietary nutrition standards scientifically,and achieving reliable dietary rules.?3?Expanding the functions of military health institutions in order to ensure the duty of supervision and intervention.?4?Standardizing the nutrition behavior of the soldiers in plateau to enhance their physical quality.?5?Accelerating the special nutritional supplements and food to fill the practical needs of medical service at plateau.In summary,we investigated the status and requirements of army dietary service.The improper dietary pattern,the short of nutrition associated common knowledge,deficiency of vitamins and minerals and improper fat-protein-carbohydrate proportion are related with impaired work capacity and chronic high-altitude disease.We investigated the indices of targeted troops under healthy conditions and revealed the requirement in diet service of high-altitude army.Based on those data,we propose some available improvement approaches.Besides,the animal experiments offer some possible effective nutrient supplements,such as vitamin B complex,fish oil and sodium pyruvate/alanine mixtures.Those nutrients could potentially improve the abilities and keep fit for high-altitude armies. |
PDF Full Text Request