Unit 1 Vitamins and Minerals

Unit1VitaminsandMineralsPartAHealthReportFromAtoZinc:TheStoryofVitaminsPartBHealthQuizVitaminDeficiencyvs.VitaminToxicityTranscriptsW:Whatareallthosepillsyou'retaking?M:Vitamins.I'mreallyintomyhealththesedays.Itakeapillfornearlyeveryvitaminmybodyneeds.I'minsuringmyselfagainstvitamindeficiency.W:Ihopeyouknowwhatyou'redoing.Justasvitamindeficiencycanmakeyousickso canvitamintoxicity.Vitaminscanbeverydangerousifyoutaketheminhigh quantities.M:Oh,youmeanvitaminsAandD.I'veheardaboutthat.Idon'tunderstand,though,whyit'sokaytotakelotsofonevitamin,butnotanother.W:Firstoff,vitaminsAandDarethemostlikelytomakeyousickifyoutaketoomuchofthem,buttheyaren'ttheonlyvitaminsthatcanbedangerous.Allvitaminshavethe potentialtobetoxicifyouingesttoomuchofthem.PartofthereasonwhyAandD putyouathigherriskthanVitaminCandothershastodowiththewayvitaminsaredissolved.VitaminCdissolvesinwater.Thus,ifyoutakeinexcessVitaminC,your bodyflushesitoutthroughurine.VitaminsAandDdissolveinoilsandmeltedfat. Whenyoutaketoomuchofoneofthesevitamins,ratherthanflushingtheexcessout, thebodystoresthesurplusinfatorinfattytissuessuchastheliverandthebrain. Accumulationofwaterinthebrain,severeheadaches,andbirthdefectsarejustthree oftheproblemstoxiclevelsofVitaminAcancause.Ifyoukeeparelativelywell-balanceddiet,you'llmostlikelygetthevitaminsyourbodyneedswithouttheuseofsupplements.VitaminC–TheWonderWorkerTranscriptsMedicalexpertsrecommendatleast60milligramsofvitaminCeveryday.However,somepeoplerequirehigherquantitiesofvitaminC,dependingontheirlifestyle.ResearchhasshownthatcigarettesmokehasanegativeimpactonthemetabolismofvitaminC.SmokershavebeenfoundtohaveamuchlowerlevelofvitaminCinthebloodthandononsmokers.TheFoodandNutritionBoardrecommendsthatsmokersconsume100mgofvitaminCaday.Besidessmokers,chronicalcoholconsumers,diabeticsandevenyoungwomenhavebeenfoundtoneedhigherlevelsofvitaminCthantherecommended60milligrams.MedicalexpertscallvitaminCthe'wonderworker'becauseitisinvolvedinanumberofkeylifesustainingfunctionsofpreventingmanyillnesses,fromeverydayailmentssuchasthecommoncoldtodevastatingdiseasessuchascancer.Primarily,vitaminCisinvolvedincollagenformation,whichisthecementingmaterialthatbindscellstogether,andisanessentialconnectivetissueproteininthebody.Wheneverthebodyiswounded,collagengluestheseparatedtissuestogethertoformascar.VitaminCalsostrengthensandprotectstheimmunesystembyfightingoffforeigninvadersandbystimulatingtheactivityofantibodies.RecentresearchhasindicatedthatvitaminCisanimportantanti-oxidantandmaybeassociatedwithdelayedagingandpreventionofdiseaseslikecancerbydestroying'freeradicals,'themoleculesassociatedwithagingandcelldamage.Althoughwedependonthisnutrientformanyaspectsofourbiochemicalfunctioning,humanbeingsareonlyamongahandfulofanimalspeciesthatcannotproducetheirownsupplyofvitaminC.Wethereforemustobtainitfromourdiet.SincevitaminCisawater-solublevitamin,thebodyeliminatesit,whichmeanspeopleneedacontinuoussupplyofitintheirfood.Vitamins–fromFoodorfromPills?TranscriptsHaveyouevereyedaplateofboiledspinachandwonderedwhetherit'sbettertogetyourvitaminsfromfoodorfrompills?Thegoodnewsisthatoverthepasthundredyears,pharmaceuticalmanufacturershavemanagedtoidentifythemostusefulandstableformsofeachvitamin,so,ifwe'restrictlyspeakingaboutvitamins,inmostcasespillsarejustaseffectiveasfood.You'reprobablywonderinghowthatcanbewhenvitaminpillsaresynthetic,andboiledspinachisallnatural.Well,whenitcomestovitamins,syntheticdoesn'tmeaninferior.Eventhosepillstoutedasall-naturalcontainsomesynthetics–otherwisethey'dbethesizeofgolfballs.Therearesomevitamins,likevitaminE,thatareabsorbedmoreeasilyintheirnaturalform,butyoucangettheminpillformtoo.Youjusthavetolookforthem.Ingeneral,whenyou'reshoppingforvitamins,don'tbefooledbyfancy-schmancysuper-supplements.Justmakesurethepillyou'rechoosingcontainsonehundredpercentoftherecommendeddailyallowanceofvitaminsandnutrientsandcheckwhethertheboxhasaUSPsymbol,whichmeansthepillshavebeenshowntodissolvewellinyourstomach.Ifthepillsdissolvewell,chancesarethey'realsoabsorbedwelltoo.Keepinmind,however,thatitispossibletogettoomuchofanutrient,whichiswhythegovernmenthaspublishedtheupperlevelsontheamountsyoucansafelyconsume.Second,somevitaminsarebetterabsorbedwhenthey'reincertainfoods.Forexample,yourbodyabsorbsironbetterwhenyoutakeitwithsomeorangejuice.PartCMedicalMysteryCalciumTranscriptsCalciumisamineralessentialforsupportingthestructuresofbonesandteeth.Forthisreason,99percentofthecalciuminthebodystoredintheseareas.Calciumisalsoneededforbloodvesselcontractionsandmuscleusage.Inaddition,thismineralaidsthesecretionofessentialhormonesandenzymesinthebody.Ashortageofcalciumcanleadtobonebreakdownbecausethebodymustusethebones’calciumdeposittomaintainnormalnerveandmusclefunctions.Theresultingbonelosswhichusuallyoccursinolderpeopleisknownasosteoporosis.Whilecalciumisessentialtothenormalfunctioningofthebody,itneedssomehowgettingintothebloodstream.VitaminD,whichthebodymakesafterbeingexposedtothesun,playsaroleinthecalciumabsorption.VitaminDisakeythatallowsthecalciumbehindthedoortoleaveyourintestineandenterthebloodstream.Forthisreason,calciumneedsVitaminDtodoitsjob.Mostadultsneed1000mg.calciumperdayalthoughpeopleover51shouldincreasetheirintaketo1200mg.Calciumisnotmadeinthebodybutisfoundindairyproductslikemilk,cheeseandyogurt.Broccoli,breadandalmondcanalsoprovidethisvitalnutrient.VegansandpeoplewhoarelactoseintolerantareparticularlylikelytosufferfromcalciumshortagesandmaybenefitfromtakingadailysupplementBeawarethatsolidacidswhicharefoundinplantssourceslikespinachandsoycanpreventoptimalabsorptionofcalcium.Morethan2500mg.ofcalciumadaycanresultinnegative-effects-likefunction,decreasemineralabsorptionandhypercalcemiawhichishighcalciumlevelintheblood.Calciumisessentialforbonegrowthandneversystemfunctionsbuttoomuchofthemineralcanbeharmful.PotassiumTranscriptsM:Hi.MindifIjoinyouforlunch?W:Grabaseat.M:Iseeyou'reeatingaconventionalmealofabanana,asandwich,andsomevegetables.W:Iguessyoucouldcallitconventional.Whatareyoueating?M:I'vegotatwo-literbottleofThirstBusterSportsDrink,andavitamin.It'smynew high-techdiet.W:Idon'tgetit.M:Ilearnedthatahigh-sodiumdietmightcausehighbloodpressure,andthatit'simportanttobalancesodiuminyourdietwithpotassium.Potassiumhelpsthebody getridofextrasodiumandalsohelpstomaintainwaterbalance.Plus,astudy suggeststhateatingadiethighinpotassiumcanhelppreventstrokes.W:Thatmakessense,buthowdoesitexplainyourliquidandvitaminlunch?M:Ifigurethatsincemydietusedtobesohighinsalt,I'llmakeupforitnowbyeating lotsofpotassium,likethissportsdrinkandpotassiumsupplementpill.W:Whatmakesyouthinksportsdrinksarehighinpotassium?M:Commercials.Haven'tyouseentheonewhereaguygulpsdownaThirst Busterandthenanimageshowsallthenutrientsandstuffflowingthroughhisbody?There'spotassiuminthere.See,itsayssorighthereinthelistofingredients.W:Icanseethat,butsportsdrinksareaprettypoorsourceofpotassium,evenifyou exercisealot.Andsupplementsarenosubstituteforrealfood.Frankly,yourlunch isn'tverynutritious.Ifyouneedmorepotassium,eatfreshfruitsandvegetablesanddrinkmilk.M:OK,fine.Theregoesmybrillianthightechdietidea.W:Here,haveabanana.M:Thanks.IronDeficiencyorIronLoading?TranscriptsM:DidyouknowthattheWorldHealthOrganizationsaysthatirondeficiencyis thenumberonenutritionaldisorderintheworld,withoverthirtypercentofthe world'spopulationnotgettingenoughofit?Justtobeonthesafeside,IguessIbetterpickupasupplementonmywayhome.W:Actually,justtobeonthesafeside,youreallyshouldn't.Indevelopedcountries liketheU.S.,mostadultmenandpostmenopausalwomenalreadygetenoughiron fromtheirdiets.Imean,don'tyouknowwhathappensifyougettoomuchiron?M:Hmm!Youbecomemagneticandstartattractingpaperclips?W:Actually,ourbodyisveryefficientinabsorbingironandmuchlessefficientingetting ridofit.Thismeansexcessironisstoredinorgansliketheheartandliver,eventually causingcirrhosisorheartfailure.Also,gettingtoomuchiron,orironloading,is associatedwithdepression,arthritis,impotence,anddiabetes,amongother conditions.M:Youknow,Ihadnoidea.W:Andyou'renotalone.Thisiswhyyoushouldn'ttakeironsupplementsunlessyourdoctorprescribesthem.Youshouldalsodrinklessalcoholandeatfoodsfortified withiron,likeprocessedmeat,inmoderation.M:You'rescaringme.Ilovethatprocessedmeat.Okay,sosupposeIgotothe doctorandshetellsmeI'mironloaded.DoesthatmeanI'mdoomed?W:No,no--youcaneasilyloweryourironbydonatingblood,whichisalsowhyiron loadingisrarerinmenstruatingwomen.Plus,therearedrugsyoucantakethatblock ironabsorptionuntilyourlevelsarebackdowntonormal.PartDMedicalHistoryTheStoryofVitaminsandBeriberiTranscriptsThewordberibericomesfromtheSinghalesewordforextremeweakness.Weaknessisthefirstsymptomofberiberi.Afterthat,neuritis,edema,paralysisandheartfailure!It'snofun.BeriberibecameagreathorrorincolonialAsiaduringthenineteenthcentury.FinallyPasteurfoundthatmicrobescausedisease.So,in1886,theDutchEastIndiaCompanysentateamtoJakartatofindtheoffendingberiberigerm.Theteamputblood,saliva,andurineunderthemicroscope.Theytriedeverythingandfoundoutnothing.Finally,afterninemonths,theylefttheiryoungestmemberinchargeofatinypermanentstation.Theygaveupandwenthome.TheyoungmanwasChristianEijkman.Fortenyearshekeptworkingontheproblem.Atonepoint,thechickensatthestationcamedownwithberiberi-likesymptoms.Theyweresickforseveralmonths.Severalevendied.Thentherestrecovered.AtfirstEijkmanshruggedthatoff.Thensomethingcaughthiseye.Thechickensgotsickafterausualshipmentofbrownricehadn'tshownup.Thecookhadprovidedwhitericeforthem.Afterawhile,thesuperintendentfoundout.Hesaid,"Stopthis!Whitericecoststoomuch!"Theyswitchedthechickensbacktobrownrice.Thatwaswhentheygotwell.Polishedwhitericewasa19th-centuryrefinement.Maybeitheldthesecret.SoEijkmanwenttolocaljailstocheckmenus.Wheretheyservedbrownrice,therewaslittleberiberi.Wheretheyservedwhiterice,beriberiwasaterribleproblem.Whatdidthatmean?Eijkmandecidedthatgermsdidn'tcauseberiberiafterall.Thericemustholdsomekindofpoison.Thebrowncoloredbranmustcarrytheantidote.Thatsolvedtheimmediateproblem.Buthisexplanationwasfaroffthemark.Yearslater,aPolenamedCasimirFunkrealizedwhatwasgoingon.Thehuskscontainedanutrientthatwemusthave,butwhichthebodycan'tproduce.Hefoundthesenutrientscomeinotherfoodsaswell.Funkgavethemaname.Hecalledthemvitamins.ThevitamininricebranisthiamineorvitaminB-1.