【作者】 王劼；

【导师】 宁正祥； 霍军生； 孙静；

【作者基本信息】 华南理工大学 ， 食品科学， 2010， 博士

【摘要】 微量营养素摄入不足不仅在贫困地区和流动性群体中发生,也是我国普遍存在的营养问题,特别是铁、锌、钙、维生素A、硫胺素(VB1)和横黄素(VB2)等微量营养素缺乏严重。营养素缺乏产生诸多不利的健康后果。其中缺铁性贫血(iron deficiency anemia, IDA)仍然是全球范围内最主要的营养缺乏病之一。铁缺乏或IDA会影响有氧能力、日常体力活动、认知能力和学习成绩等。本文调查了学生的膳食营养素摄入状况,学生膳食营养素摄入量没有完全达到RNI/AI要求。能量摄入量不足90%RNI,来源比例失调,蛋白质和脂肪供能比例不足,而碳水化合物供能偏高。蛋白质摄入量低于80%RNI。膳食维生素A摄入量低于60%RNI,供给严重不足。VB1低于或接近80%RNI,摄入量不足。VB2摄入量低于60%RNI,供给严重不足。膳食钙摄入量低于30%AI,钙摄入严重不足。女生的膳食铁摄入量低于AI,女14y~仅达到75%AI,同时膳食铁来源不平衡,动物性食物来源的铁不足10%。锌摄入量不足60%RNI,锌供给严重不足。学生的豆类及制品的摄入量不足推荐量的50%,肉、禽低于推荐量的60%,蛋类摄入量偏低。通过身高标准体重判断,学生中存在较严重的营养不良情况,营养不良率为30.3%(男: 25.7%,女: 37.1%)。机体营养素水平测定结果显示学生中存在较高的贫血检出率和铁缺乏检出率,贫血率为11.4%(男: 10.1%,女: 13.5%),铁缺乏率为16.9%(男: 12.2%,女: 24.2%),男、女生铁缺乏率差异显著( 2=13.270, P=0.0003)。缺铁性贫血(IDA)是主要的贫血类型,约50%的贫血男生为IDA,而有79%的贫血女生为IDA,男、女生IDA检出率差异显著( 2=5.788, P=0.016)。微量元素锌、VA、VB1和VB2缺乏率和不足率较高。锌缺乏率为34.8%(男: 33.6%,女: 36.8%)。VA缺乏和边缘缺乏率为20.9%(男: 21.4%,女: 20.3%)。VB1缺乏率为7.4%(男: 6.0%,女: 9.5%),VB1不足率为26.9%(男: 25.3%,女: 29.3%)。VB2缺乏率为8.7%(男: 10.4%,女: 6.0%),VB2不足率为16.8%(男: 14.3%,女: 20.7%)。采用多营养素强化食品干预10个月后,学生营养不良状况改善。中度营养不良率下降到1.85%(男: 1.12%,女: 3.26%),轻度营养不良率下降到13.65%(男: 10.61%,女: 19.57%)。营养干预后受试者机体铁营养状况显著提高,贫血率下降到2.5%(男: 2.1%,女: 3.1%),铁缺乏率降低至2.6%(男: 2.2%,女: 3.3%)。营养干预后学生血清锌、血清维生素A、尿VB1和尿VB2水平显著提高,缺乏率下降。锌缺乏率下降到14.1%(男: 14.1%,女: 14.0%);VA缺乏率下降到1.5%(男: 1.7%,女: 1.1%),边缘缺乏率下降到6.4%(男: 6.4%,女: 6.5%);尿VB1缺乏率下降到0.0%,不足率下降到4.5%(男: 5.3%,女: 3.1%);尿VB2缺乏率下降到0.0%,不足率下降到7.9%(男: 8.9%,女: 6.2%)。结果表明采用综合食物营养强化能够显著提高受试者机体营养状况,降低营养素缺乏及不足发生率。IDA降低学生的最大摄氧量(VO2max)、VO2max/W和VO2max/FFM。铁缺乏不贫血(IDNA)女生的VO2max/FFM显著低于正常组。IDA学生的最大耐受时间显著低于正常组和IDNA组(P<0.0001)。IDA学生在自由活动时的平均净心率(AHR)和能量消耗(EE)显著降低。同时,IDA学生进行有氧活动的时间也显著减少。学生休闲时的AHR与休闲指数呈负相关(男: r=-0.354, P<0.0157,女: r=-0.20, P<0.19),与运动指数成正相关(男: r=0.69, P<0.0001,女: r=0.311, P<0.0377)。有氧活动时间与Hb值相关(男: r=0.49, P<0.001,女: r=0.60, P<0.0001)。铁强化酱油干预显著提高IDA组的有氧能力和休闲期间进行有氧活动的强度和时间。IDNA组补充铁后VO2max/FFM显著提高(男: P<0.0001,女: P<0.01)。铁缺乏的程度对基本认知能力产生不同的影响,IDNA降低短时记忆功能,而IDA降低知觉反应速度、工作记忆、短时记忆、以及涉及复杂认知加工过程的思维效率。铁缺乏的程度对注意力各品质产生不同的影响,IDNA和IDA学生的注意力总分均显著低于正常学生(P<0.01)。不同程度的铁缺乏都会降低注意分配和注意稳定性,当铁缺乏严重到导致IDA时,还会影响注意转移能力。IDNA和IDA学生的语文和数学Z标准分显著低于正常学生,而英语和思品成绩没有差异。铁强化酱油干预显著提高IDA学生的知觉反应速度、心算效率和短时记忆,但工作记忆工作不能得到完全补偿;IDNA学生的短时记忆功能显著提高(P<0.05)。铁强化酱油干预显著提高IDNA和IDA学生的注意力总分和各品质得分。IDA组的IQ显著低于NA组,这种差异不能通过铁剂补充来纠正。铁强化酱油干预显著提高IDNA和IDA学生的语文和数学成绩,与正常学生的差异消失。更多还原

【Abstract】 Micronutrients insufficiency, especially in iron, zinc, calcium, Vitamin A, VB1 and VB2, is one comman nutrition question in our country which takes occur not only in the poor area and fluid community but also other communities. The nutrient deficiency has many disadvantageous healthy consequences. Iron deficiency anemia (IDA) is one of high prevalence nutrient deficiency around world. Iron deficiency and IDA affect aerobic work capacity, daily physical activity, cognitive ability, academic achievement and so on.This article investigated student’s dietary nutrients intakes. The results show that dietary nutrients intakes of students have not met requirement of RNI/AI completely. Energy intake is less 90%RNI with the imbalance energy resource for the energy from protein and fat is lower while the energy from carbohydrate is higher. Protein intake is less 80%RNI. Dietary vitamin A intake is lower than 60%RNI being seriously insufficient. Dietary vitamin B1 intake is lower than 80%RNI. Dietary vitamin B2 intake is lower than 60%RNI, being seriously insufficient. Calcium intake is lower than 30%AI, being seriously insufficient. Dietary iron intake for female student’s is lower than AI. The dietary iron resource is not balanced for the proportion of heme iron is less than 10%. Dietary zinc intake is lower than 60%RNI, being seriously insufficient. The legumes intake is lower than 50% recommendation quantity; the meat intake is lower than 60% recommendation; the egg intake is somewhat low.Through the weight for height standard, the prevalence of malnutrition of students is serious, being 30.3% (male: 25.7%, female: 37.1%). Student has the high prevalence of anemia being 11.4% (male: 10.1%, female: 13.5%)and iron deficiency being 16.9% (male: 12.2%, female: 24.2%). The difference of iron deficiency prevelance between male and female students is significant ( 2=13.270, P=0.0003). Iron deficiency anemia (IDA) is the main anemia type and approximately 50% anemia male is IDA while 79% anemia female is IDA. The difference of IDA prevelance between male and female students is significant ( 2=5.788, P=0.016). The prevalence of zinc, VA, VB1 and VB2 deficiency is high. Zinc deficiency rate is 34.8% (male: 33.6%, female: 36.8%). VA deficiency rate is 20.9% (male: 21.4%, female: 20.3%). VB1 deficiency rate is 7.4% (male 6.0%, female 9.5%), and marginal deficiency rate is 26.9% (male 25.3%, female 29.3%). VB2 deficiency rate is 8.7% (male 10.4%, female 6.0%), and marginal deficiency rate is 16.8% (male 14.3%, female 20.7%).By 10 months intervention of the multi-nutrients fortified food, malnutrition prevelance is decreased. Moderate malnutrition rate drops to 1.85% (male: 1.12%, female: 3.26%), while mild malnutrition rate drops to 13.65% (male: 10.61%, female: 19.57%). Iron nutritional status is obviously enhanced, for anemia rate drops to 2.5% (male: 2.1%, female: 3.1%), and iron deficiency rate drops to 2.6% (male: 2.2%, female: 3.3%). Zinc, VA, VB1 and VB2 level are obviously enhanced. Zinc deficiency rate drops to 14.1% (male: 14.1%, female: 14.0%). VA deficiency rate drops to 1.5% (male: 1.7%, female: 1.1%), and marginal deficiency rate drops to 6.4% (male: 6.4%, female: 6.5%). VB1 deficiency rate drops to 0.0%, and marginal deficiency rate drops to 4.5% (male: 5.3%, female: 3.1%). VB2 deficiency rate drops to 0.0%, and marginal deficiency rate drops to 7.9% (male: 8.9%, female: 6.2%). The comprehensive food nutrition fortification can obviously enhance the body nutritional status, and decrease the prevalence of nutrients deficiency.IDA impaired the VO2max, VO2max /W and VO2max /FFM. There was no difference on VO2max and VO2max/W for IDNA subjects compared with normal iron status subjects. VO2max/FFM for female IDNA was lower than normal females, however there was no different between IDNA and normal males. The maximual work time for IDA subjects was significantly lower than both IDNA and normal subjects. Aerobic activity and energy expenditure(EE) at leisure in IDA subjects were significantly lower than IDNA and normal subjects. No difference was found in average net HR(ANHR) and EE at work among IDA, IDNA and normal subjects. ANHR at leisure was negative correlated with leisure index(male: r=-0.354, P<0.0157; female: r=-0.20, P<0.19), and positive correlated with leisure index(male: r=0.69, P<0.0001; female: r=0.311, P<0.0377). Aerobic activity time was positive correlated with Hb concentration (male: r=0.49, P<0.001; female: r=0.60, P<0.0001). Aerobic ability increased significantly in IDA subjects after iron supplementation. VO2max/FFM responsed to iron supplementation which indicated iron deficiency without anemia impaired aerobic capacity. ANHR increased by 8.54 (male) and 6.88 (female) beats/min and aerobic activity time increased by 5.31 minutes (male) and 5.08 minutes (female) in iron-deficient group at leisure. The strength and time of aerobic activity increased significantly for IDA subjects after iron supplementation.Iron deficient with or without anemia subjects had lower scores in basic cognitive test, and attention test of adolesence. IDNA impaired the short memory, while IDA impaired reaction speed, working memory, and efficiency of complex cognitive processing. The stage of iron deficiency had different effect on four aspect of attention ability. The score of total attention ability in IDNA or IDA was lower than normal subjects. Iron supplement by EDTA iron fortified sause result in an improvement in cognitive performance for IDA or IDNA subjects. However, the working memory in IDA could not be completely compensated by iron supplementation. Iron supplement by EDTA iron fortified sause resulted in an improvement in attention performance for IDA and IDNA subjects. The scores of total attention score and attention stability in IDA subjects were still lower after iron supplement. IQ in IDA was significantly lower than normal subjects which could not be normalized by iron supplementation. The Z-score of Chinese language and mathematic were lower for IDA and IDNA subjects compared with normal iron status subjects (P<0.01). Diffecrence in Chinese language and mathematic disappeared after iron supplyment. There were not difference in foreign language and social science before and after intervention.更多还原