营养-2015第一章第9节维生素

第九节维生素(Dr.&Prof)DepartmentofNutrition&FoodHygienePAGEPAGE3PhysicalandChemicalFunctionsofAbsorptionandDeficiencyandexcessofEvaluationonthenutritionalvalueofAllowanceandFoodDefinitionofVitaminsareorganiccomponentsinfoodthatareneededinverysmallamountsforgrowthandformaintaininggoodhealth.B族&A、D、E、Fat-solubleversuswater-solublewater-ininC,H,O;N,S,Liver,fatty(VK++InfluencingfactorsforvitaminInadequateintakeofanyparticularvitamininthedietFoodisinshortThelowabsorptionandutilizationIncreasedphysiological6CategoryofvitaminCauses：Primary、Degree：Clinic、Sub-Storage

clinicalPAGEPAGE9Interactionwithothervitamin-othernutrients：associationbetweenB1、B2、niacinandenergymetabolism，theirrequirementincreasewithenergyincrease.Vitamin-vitamin：VEpromoteabsorptionandstorageofVAinliver，VEanti-oxidantincoordinationwithGPx.维生素

视黄醇视黄醛视黄酸(retinoic视黄基酯复合类胡萝卜

原原β-隐黄(beta-cryptoxanthin)-胡萝卜素(gamma-番茄红素Absorption&

Fatty

Mucousofsmall9FunctionsofvitaminThebestcharacterizedfunctionofvitaminAisitsroleintheretinaof.Darkadaptation：theprocessofadjustingtheeyestolevelsofRhodopsin：abiologicalpigmentinthephotoreceptorsoftheretinaimmedia yphotobleachesinresponsetolightCellgrowthandTheretinoicacidModulatinggeneexpressionbyactivationofnuclearImmuneIthelpsmaintainthehealthofepithelialtissuesagainstbacterial,parasitic,andviralattack;itsupportsterationofTlymphocytes.AnticancerAtotalof388newcasesoflungcancerwerediagnosedduringthe73,135-yearsoffollow-up(meanlengthoffollow-up,4.0years).Theactive-treatmentgrouphadarelativeriskoflungcancerof1.28,ascomparedwiththeplacebogroup，therelativeriskofdeathfromanycausewas1.17.Onthebasisofthesefindings,therandomizedtrialwasstopped21monthsearlierthanplannedWeconductedamulticenter,RCT—theBeta-CaroteneandRetinolEfficacyTrial—involvingatotalof18,314smokers,formersmokers,andworkersexposedtoasbestos.Theeffectsofacombinationof30mgofbetacaroteneperdayand25,000IUofretinol(vitaminA)intheformofretinylpalmitateperdayontheprimaryendpoint,theincidenceoflungcancer,werecomparedwiththoseofplacebo.1IU维生素A=0.3μg视黄醇当量我国成人维生素A推荐摄入量（RNI），为800μgRE/d，女性为700μgRE/d。UL在成人为3000μgRE/d，孕妇为2400μgRE/d。DeficiencyofVitaminVitaminAdeficiencyoccursmostoftenandremainsamajorprobleminlargeareasofdeveloworld,beingthesinglemostcommonpreventablecauseofblindness.TheprevalenceofVAdeficiencyininfantsandchildrenarehigherthanthatinadultsInadults,excessivealcoholconsumptionreducesliverreservesofVA.DigestivetractdiseasesincreaseriskofVAExcessofvitamin yandchronicallyLargedosesofVAcausenausea,vomitingandExtremelyhighdosescanproveThechronictoxicityofVAaffecttheskin,centralnervoussystem,liverandbones.CarotenoidsdonotcausehypervitaminosisNutritionalNutritionalstatusofVitamininsufficiency（marginalstatus）Identify:biochemicalclinicalsymptomphysiologicalresponsesdietaryBiochemicaltheplasmaleveloftherelativedoseresponseRDR（％）=

Nutritionalevaluationof Plasmalevel100-RDR50-plasmaretinolbindingthefastingplasmaconcentrationofretinolremainsconstantoverawiderangeofintakesnormalsignandAssessmentoftheDarkadaptationDietaryrequirements&foodCreateastandardizedmeasurementbasedonretinol,calledretinolactivityequivalents(RE)1μgβ-胡萝卜素=0.167μgDietaryrequirements&food mendedbyCNSin2000:RNI800µgRE/dformaleand700µgRE/dforfemaleadults;UL3000µg/dforadults.Foodsouces:VAfromanimalprovitaminAcarotenoidfromdark-greenandyelloworangevegatables.VitaminVitaminDisnotstrictlyavitamin,ratheritistheprecursorofthehormonesinvolvedincalciumhomeostasisandtheregulationofcellproliferationanddifferentiation酵母菌或麦角固维生素皮下7-脱氢胆固

维生素7-维生素Absorption&VitaminDinDeficiencyandWhenexposuretosunlightisinadequateanddietaryintakeisrestricted,deficiencyinvitaminDoccurs.ThemajorsymptomsofvitaminDdeficiencyarericketsinyoungchildrenandosteomalaciainadults.ExcessivelyhighintakesofVDareassociatedNutritionalSerumlevelsof25（OH）-< 20ng/mL~ > 五、FoodsourcesofvitaminTherearefewdietarysourcesofCod-liverFish

东群19世纪80年代，当时荷东群19世纪80年代，当时荷下荷兰医学家艾伊克曼，1929年生理学或医学奖得 1.FunctionsofThiaministhevitaminportionofthecoenzymethiaminpyrophosphate(焦磷酸硫胺素,TPP) Citricacid2.Helpsynthesizeregulate1.Produceenergyfuelnerveperipheralnervous CentralnervoussystemamongFunctionsofOthers乙酰胆gastrointestinal乙酰胆gastrointestinalmotilityglandularsecretionThiaminThiaminrequirementsdependlargelyoncarbohydrateTheclassicalthiamindeficiencydisease,beriberi,affectingtheperipheralnervoussystem,isnowrare.Thiamindeficiency,leadingtocentralnervoussystemdamage,isasignificant,andunderdiagnosed,problemamongalcoholicsandpeoplewithHIV-AIDS.ThiaminTherearenoreportsofthiamintoxicityfromeitherfoodorsupplementsThereisnotsetatolerableupperintakelevel(UL)forthisnutrient.Largedosesofthiaminappeartoberelativelyinnocuous,inaddition,thekidneysrapidlyexcreteexcessthiaminviaurine.Assessmentofthiaminnutritionalurinaryloadtest（5mgisgivenorally，urinaryexcretionlevelsofthiaminafter4h） deficiency100~199μg >200 >400 Theratioofurinarythiaminandtheactivationofapo-transketolasein （红细胞转酮醇酶系数Dietaryrequirements&foodThiaminrequirementsdependlargelyonenergymendedbyCNSin2000:richsource：yeast、corn、bean、drygoodsource：milkeggfishmeat、fish、internalorganspoorsource：vegetablefruit.VitaminB2（核黄RiboflavinRiboflavinispartoftwoimportantcoenzymes,FMNandFADwhichareoxidizingagents.RiboflavinRiboflavindeficiencyisrelativelycommon,butrarely(ifever)fatal,becausethereisefficientconservationofthevitaminindeficiency.RiboflavindeficiencycancausesecondarydeficiencyofironandfunctionaldeficiencyofClincially,deficiencyischaracterisedbylesionsofthemarginofthelipsandcornersofmouth,andasebhorroeicdermatitis. 口角(angular唇炎 舌炎Assessmentofriboflavinnutritional细胞谷胱甘肽还原酶活性系数(erythrocyteglutathione eactivationcoefficient，EGRAC)activitycoefficient,AC＜1.2isnorml;＞1.4isUrinaryloadingVB2清晨口服维生素B25mg，4h尿中排出 或测任意一次尿中核黄素与尿肌酐比 Dietaryrequirements&food mendedbyCNSin2000:RNI1.4mg/dformale1.2mg/dforfemaleULRiboflavinispresentinmostfoodsalthoughthebestsourcesaremilkandmilkproducts,eggs,liver,kidney,yeastextractsandfortifiedbreakfastcereals.维生素.八VitaminVitaminCisprobablythemosttalkedaboutvitaminandiscertainlytheonemostwidelyusedasasupplement.Thechemicalnameforvitamin