特殊人群的营养价值.ppt
不同人群的营养 Life Cycle Nutrition,1.Nutrition During Pregnancy,The Physiology of Pregnancy,A womans body undergoesmany changes during pregnancy to develop and maintain the systems necessary to support the growing fetus.,Hormones changes Gastrointestinal changesDelay in gastric emptyDecreased gastric acidityDigestive discomforts morning sickness,heart burnCardiovascular system Blood volume increases by 50%Increase in cardiac outputDecrease in albumin concentrationRenal function changesweight gain,总体重增加:1113kg胎儿:3.3kg胎盘、羊水：1.5kg子宫：1.0kg血液：1.2kg乳房：0.4kg细胞间液：1.5kg脂肪：24kg,Recommend Weight Gain During Pregnancy,The nutritional needs of pregnancy,During pregnancy,a womans nutrient intake andbody stores must provide all the nutrients needs to support the growth and development of the baby while continuing to meet the mothers needs.,Energy A typical pregnancy has been estimated to require an additional 55000 kcalories.Additional 200 kcal/day during the second and third trimesters.Protein Protein needs are also increased during pregnancy to provide for RNI:+5g/d 1st trimester+15g/d 2nd trimester+20g/d 3rd trimester,MineralsCalcium Pregnant women absorb more of the calcium they consume and lose less calcium in the urine than do nonpregnant women.The fetus retains about 30 grams of calcium over the course of gestation.Most of the calcium is deposited in the last trimester when the fetal skeleton is growing most rapidly and the teeth are forming.RNI 800mg 1st trimester 1000mg 2nd trimester 1200mg 3rd trimester food source:milk and dairy products,Iron Iron deficiency anemia low birth weight preterm delivery Babies born prematurely may not have had time to accumulate sufficient iron,but babies born at term usually have adequate iron even if the mother is deficient.RNI 15mg 1st trimester 25mg 2nd trimester 35mg 3rd trimester food source:red meats,leafy green vegetables,fortified cereals iron supplement,Zinc Zinc deficiency during pregnancy is associate with an increased risk of fetal malformation and low birth weight.RNI 11.5mg/d 1st trimesrer 16.5mg/d 2nd trimester 16.5mg/d 3nd trimester Iodine Iodine deficiency during pregnancy increases the risk of stillbirth spontaneous abortion and can result in condition in the offspring called cretinism(呆小病）.RNI200g/d,Folic Acid and Vitamin B12 Folic acid and vitamin B12 are essential for cell division,Adequate folate intakes is crucial even before conception because rapid cell division occurs in the first days and weeks of pregnancy.Folate is believed to be essential for proper formation of neural tube.Deficiencies of folate and vitamin B12 can also result in megaloblastic anemia.,Vitamins,megaloblastic anemia:reticulocytes cells must be constantly replenished via new synthesis of DNA and RNA,Vitamin A High dietary intakes of preformed vitamin A(10,000IU)can cause birth defects in humans and animals.Vitamin DVitamin C,Maternal Malnutrition and Pregnancy Outcome,Low birth weightPrematureIntrauterine growth retardationStillbirthIncreased early newborn deaths Malformation,The physiology of lactation,2.Nutrition requirement on Lactation,Maternal Nutrient Needs during lactation,The need for energy and many nutrient is even greater during lactation than during pregnancy.This is because the mother is still providing for all of the nutrient needs of infant who is growing faster and is mover active then the fetus.,Energy Contained in the milk itself Needed to synthesize the components of the milk RNI:+500kcal Protein The protein needed to produce milk increase maternal protein needs RNI+20g,Water When fluid intake is low,the mothers urine will become more concentrated to conserve water for milk production.To avoid dehydration and ensure adequate milk production,fluid intak should be increased by about 1L/d.,RNIs of some element and vitamines,lactation pregnant non-pregnant Calcium 1200mg 1200mg 800mgIron 25mg 35 mg 20mgVit.A 1200 g 700 g 700 gVit.B1 1.8mg 1.5mg 1.3mgVitB2 1.7mg 1.7mg 1.2mg,Energy 1.Basal metabolic requirement2.Specific dynamic effect3.Physical activity4.Tissue growth5.Fecal loss 3 times greater than in adults,8595kcal/kg 4050%come from fat high energy density small stomach important for nervous system development,3.Infant nutrition,Protein Tissue growth 1.62.2g/kg Total protein intake should not exceed 20%of energy needs.Fat energy/%00.5 year：45%50%0.5:35%40%EFA development of nervous system,Minerals and Vitamins Special emphasis on calcium and iron IronIron-fortified infant formulasIron-fortified cerealWater Need greater than that of an adult Infant 120150ml/kg/day,Breast Feeding,Nutritional Qualities of Human Milk,Human milk is very different in composition from cows milkUnless altered,cows milk should not be used in infant feeding until the infant is 12 months old.,position of breast milkprotein approximate 1/3 as in cows milk whey proteins:casein=80:20(18:20in cows)smaller and more flocculent curd easier digestion,greater absorption,soft stools lipids most variable macronutrient in human milk fine emulsification active lipase higher degree of unsaturation,carbohydrate lactose is higher lower intestinal PH improve the absorption of nitrogen,calcium and magnesium encourages the growth of fermentative rather than putrefactive bacteria components of myelin and collagen,minerals calcium:phosphorus 2:1(1:1 in cows milk)copper is higher iron is slightly higher,utilized more efficiently vitamins twice as much vitamin A and niacin four times as much as ascorbic acid and vitE vitamin D is low,Immune factor,S-IgA 免疫球蛋白Lactoferrin乳铁蛋白Lactobacillus bifidus双歧因子Lysozymes溶菌酶,Immune factors of human milk and cows milk immune factors human milk cows milk Lactoferrin(g/L)1.5 痕量 Lysozymes(g/L)0.5 0.0001 lgA（g/L）1.0 0.03 lymphocyte(个/ul）800 0 Lactobacillus bifidus(个/ul）有 未检出,初乳(colostrum)antibodies lactobacillus bifidus factor facilitates the passage of meconium(胎粪)过渡乳(transitional milk)成熟乳(mature milk),composition of colostrum and mature milk,colostrum mature milkprotein（g/L）22.90 10.60S-IgA(mg/L)21.00 10.00Lactose(g/L）57.00 71.00lipids（g/L)29.50 45.40zinc（mg/L)5.59 1.18retinol（mg/L）1.61 0.27,Advantages of Breastfeeding,Provision of immunologic and enzymatic components Optimal nutrient composition Promotes maternal-infant bonding Promotes facial/muscular development Decreased incidence of respiratory and gastrointestinal infections Possible reduced incidence of chronic diseases later in life Inexpensive and convenient Easy for infant to digest,母乳喂养幸福的源泉,每年的8月1日至7日,Introducing Solid Foods,Nutritional needPhysiological capabilitiesPhysical abilityPreventing allergies,幼儿营养与膳食nutrition and dietary of preschool children,In contrast to the rapid and usually smooth growth in the first year,the period from one to six is characterized by a slower rate of increase in both stature and weight.The slowing of the rate of growth results in a less pressing demand for nutrients than was observed in the first year.Maturation of function,control of the body,and development of social and cognitive abilities are more pronounced than somatic growth during the preschool years.,characteristics,1.physical growth,2.physiological development related to nutrition,Fine motor coordination also progress rapidly,and manipulation of objects,including food,becomes more proficient.,3.Psychosocial-biological interactions Increasing independence,ability,and socializationEffect of social,economic,and educational disadvantages of the environment become manifestDevelopment of attitudes toward food patterns of eating behavior be set during this period Setting a good example is very important,Milk and milk productsCereal grainMeat,fish,poultry,eggs and soybeanVegetables and fruitsSnack food,Food choice,Healthy eating is important in this period,Provide the energy and nutrients needed to grow and developDevelop a sense of taste and an acceptance and enjoyment of different foodsInstill attitudes and practices which may form the basis for lifelong health-promoting eating patterns,Influences on Food Choices,FamilyLifelong habits and attitudes established during the period of independence.Shared meals=better diets.Peers(particularly strong for adolescents)Media,Feeding the Young Child,Appetite and food intake may vary tremendously.Snacks contribute significantly to total days intake.Food jags are part of normal development.Choking risks,幼儿膳食的基本要求,1.Well-balance diet(平衡膳食)protein 10-15%lipids 25-30%carbohydrates 50-60%provide a wide variety of nutritious foods for children to selectgive children a large proportion of control over their food intake,especially meal size have fast foods as an occasional treat not as an everyday food.2.Rational cooking(合理烹调)适合幼儿消化功能特点减少烹调过程中营养素的损失,3.合理的进餐三餐一点:早餐 20-25%中餐 30-35%午点 10-15%晚餐 30%help children adapt to the social timing of mealshave mealtimes at an appropriate time for young children4.培养良好的饮食习惯 定时、定点、定量进餐，不暴饮暴食 不偏食、挑食 培养使用杯、匙、碗、筷自己进食 不以食物作为奖惩手段 avoid using rewards or forcing or coercing a child to eatavoid force feeding childrenavoid overfeeding,5.良好的进餐环境 have mealtimes together as a family(when possible)limit distractions at mealtimes6.注意饮食卫生,青春期的营养和膳食nutrition and dietary of adolescents,青春期早期：growth spurt青春期中期：sexual maturation青春期晚期：physical growth maturity,青春前期 青春后期,青春期少女的生理和心理,青春期的生理特点1身高和体重生长突增（growth spurt）体成分（body composition）The growth spurt usually begins around 10 years of age in girls and 12 years of age in boys.In both sexes,an average of 23cm is added to height and 20-26kg to weight.Before adolescence,both girls and boys have an average of 18%body fat.During adolescence this increases to about 28%in girls and decreases to about 15%in boys.,2性器官的发育和第二性征的出现性器官内生殖器官：阴道、子宫、输卵管和 卵巢外生殖器官：阴阜、大、小阴唇和阴蒂第二性征：乳房、阴毛、腋毛3.各组织、器官、系统的发育,性腺,腺垂体,神经垂体,下 丘 脑,组织,肾上腺,甲状腺,LHRH FSH-RH GRH PIF PRF GRIH GRH TRH,雌激素孕激素睾丸酮,LHFSHACTHGHTSHPRL,肾上腺皮质素雄激素,兴奋抑制,青春期内分泌调节示意图,神经中枢,甲状腺素,青春期的营养需要Nutrient Requirements,影响因素：1.发育早晚 2.体力活动水平 3.个体差异,1.Energy 16岁10.0MJ（2390Kcal）18岁 8.8MJ(2100Kcal)2.Protein positive nitrogen balance 1.61.9g/kg 80g(70g),Minerals 1).Calciuml Bone grows in volume and density as well as length llength increase 0.25mm/dlWeight increase 1.2g/d,from 1500g-3000gRDA 13 1200mg/d 16 1000mg/d 18 800mg/dAI 11 1000mg/d 14 1200mg/d 18 800mg/dUL 11 2000 14 2000 18 2000,2).Iron iron is needed for:l growth of body tissuesl increase in blood volumel replacement of iron losses in menstrual blood iron-deficiency anemiaRDA 10 12mg/d 13 20mg/d 18 12mg/dAI 11 18mg/d 14 25mg/d 18 20mg/dUL 50 50 50,3).Zinc RDA 10 15mg/d RNI 11 15mg/d 14 15.5mg/d 18 11.5mg/d UL 11 34 14 35 18 374).Iodine goiter RDA 10 120g/d 13 150g/d RNI 11 120g/d 14 150g/d UL 11 800 14 800 18 1000,四维生素(Vitamins)1.Vit.A2.Vit.D3.B vitamins4.Vit.C,一日食谱举例,Anorexia nervosa,refusal to eat enough to maintain a normal body weight intense fear of gaining weight or becoming fat Sufferers are of the impression that they are fat and often see themselves as being fat even though they are obviously underweight.exercise vigorously or use slimming pills often stop menstruating.often very secretive about their eating habits.,That autumn,Heather was rejected by Oxford.By now it was evident that she was very thin.At Christmas,her behaviour led to major upsets and rows in the family.Finally,early in the New Year,her parents persuaded her to see the family doctor.When weighed at,the surgery,she was just under six stones(37 kg).It was clear now that she was suffering from anorexia nervosa.,老年营养The changes of aging,changes in cells and organs随年龄增加，体细胞数目减少，各器官功能逐渐降低.1.胃肠道(gastrointestinal tract)2.心脏(heart)3.肝脏(liver)4.肾脏(kidney),changes in body composition),1.去脂组织减少(decrease in lean body mass)每10年减少6.3%骨骼肌减少（70岁后减 少40%），内脏器官减重2.脂肪组织增加(increase in body fat)3.体内水分减少(decrease in water)4.骨密度降低 从40岁开始降低,changes in metabolism,1.基础代谢下降 减少15%20%2.蛋白质代谢 按每公斤体重计算合成降低，以去脂组织为单位计算，则比青年人增高5%10%。蛋白质分解也增加。3.脂肪代谢 合成、分解和排泄均降低，导致脂类在血管和组织堆积4.糖代谢 对葡萄糖的氧化能力减少，糖耐量下降,changes in hormone levels,1.生长激素（growth hormone）May be responsible for a decrease in lean body mass2.褪黑素（melatonin）It is involved in regulating the bodys cycles of sleep and wakefulness The decline has been hypothesized to influence aging by affecting body rhythms and triggering genetically programmed aging at a cellular level It is also an antioxidant and may enhance immune function,changes in immune function,The ability of the immune system to fight disease decline with age.Supplement of several micronutrients including zinc,beta-carotene,and vitamin E have been shown to improve immune response.,nutrient needs of older adults,Energy needs are typically reduced in the elderly This occurs for several reasons:Basal metabolic rate physical activity Can energy deprivation slow aging?,protein needs,The needs for protein dose not decline with age.Therefore an adequate diet for older adults must be somewhat higher in protein relative to energy intakeFatcarbohydrate,vitamin and mineral,Vitamin and mineral needs Do antioxidant nutrients slow aging?Are nutritional supplements necessary?,学习要点,食品营养价值的概念、评价方法INQ各类食品的营养特点不同年龄阶段的特殊营养需要,容易出现的问题,
