營養(yǎng)-2015第一章第9節(jié)維生素

第九節(jié)維生素(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.維生素

視黃醇視黃醛視黃酸(retinoic視黃基酯復合類胡蘿卜

原原β-隱黃(beta-cryptoxanthin)-胡蘿卜素(gamma-番茄紅素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維生素A=0.3μg視黃醇當量我國成人維生素A推薦攝入量（RNI），為800μgRE/d，女性為700μgRE/d。UL在成人為3000μgRE/d，孕婦為2400μgRE/d。DeficiencyofVitaminVitaminAdeficiencyoccursmostoftenandremainsamajorprobleminlargeareasofdeveloworld,beingthesinglemostcommonpreventablecauseofblindness.TheprevalenceofVAdeficiencyininfantsandchildrenarehigherthanthatinadultsInadults,excessivealcoholconsumptionreducesliverreservesofVA.DigestivetractdiseasesincreaseriskofVAExcessofvitamin yandchronicallyLargedosesofVAcausenausea,vomitingandExtremelyhighdosescanproveThechronictoxicityofVAaffecttheskin,centralnervoussystem,liverandbones.CarotenoidsdonotcausehypervitaminosisNutritionalNutritionalstatusofVitamininsufficiency（marginalstatus）Identify:biochemicalclinicalsymptomphysiologicalresponsesdietaryBiochemicaltheplasmaleveloftherelativedoseresponseRDR（％）=

Nutritionalevaluationof Plasmalevel100-RDR50-plasmaretinolbindingthefastingplasmaconcentrationofretinolremainsconstantoverawiderangeofintakesnormalsignandAssessmentoftheDarkadaptationDietaryrequirements&foodCreateastandardizedmeasurementbasedonretinol,calledretinolactivityequivalents(RE)1μgβ-胡蘿卜素=0.167μgDietaryrequirements&food mendedbyCNSin2000:RNI800μgRE/dformaleand700μgRE/dforfemaleadults;UL3000μg/dforadults.Foodsouces:VAfromanimalprovitaminAcarotenoidfromdark-greenandyelloworangevegatables.VitaminVitaminDisnotstrictlyavitamin,ratheritistheprecursorofthehormonesinvolvedincalciumhomeostasisandtheregulationofcellproliferationanddifferentiation酵母菌或麥角固維生素皮下7-脫氫膽固

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

東群19世紀80年代，當時荷東群19世紀80年代，當時荷下荷蘭醫(yī)學家艾伊克曼，1929年生理學或醫(yī)學獎得 1.FunctionsofThiaministhevitaminportionofthecoenzymethiaminpyrophosphate(焦磷酸硫胺素,TPP) Citricacid2.Helpsynthesizeregulate1.Produceenergyfuelnerveperipheralnervous CentralnervoussystemamongFunctionsofOthers乙酰膽gastrointestinal乙酰膽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 （紅細胞轉(zhuǎn)酮醇酶系數(shù)Dietaryrequirements&foodThiaminrequirementsdependlargelyonenergymendedbyCNSin2000:richsource：yeast、corn、bean、drygoodsource：milkeggfishmeat、fish、internalorganspoorsource：vegetablefruit.VitaminB2（核黃RiboflavinRiboflavinispartoftwoimportantcoenzymes,FMNandFADwhichareoxidizingagents.RiboflavinRiboflavindeficiencyisrelativelycommon,butrarely(ifever)fatal,becausethereisefficientconservationofthevitaminindeficiency.RiboflavindeficiencycancausesecondarydeficiencyofironandfunctionaldeficiencyofClincially,deficiencyischaracterisedbylesionsofthemarginofthelipsandcornersofmouth,andasebhorroeicdermatitis. 口角(angular唇炎 舌炎Assessmentofriboflavinnutritional細胞谷胱甘肽還原酶活性系數(shù)(erythrocyteglutathione eactivationcoefficient，EGRAC)activitycoefficient,AC＜1.2isnorml;＞1.4isUrinaryloadingVB2清晨口服維生素B25mg，4h尿中排出 或測任意一次尿中核黃素與尿肌酐比 Dietaryrequirements&food mendedbyCNSin2000:RNI1.4mg/dformale1.2mg/dforfemaleULRiboflavinispresentinmostfoodsalthoughthebestsourcesaremilkandmilkproducts,eggs,liver,kidney,yeastextractsandfortifiedbreakfastcereals.維生素.八VitaminVitaminCisprobablythemosttalkedaboutvitaminandiscertainlytheonemostwidelyusedasasupplement.Thechemicalnameforvitamin