The Vitamin Myth Why We Think We Need Supplements.docx

The Vitamin Myth Why We Think We Need Supplements.docx

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TheVitaminMythWhyWeThinkWeNeedSupplements

TheVitaminMyth:

WhyWeThinkWeNeedSupplements

Nutritionexpertscontendthatallweneediswhat'stypicallyfoundinaroutinediet.Industryrepresentatives,backedbyafascinatinghistory,arguethatfoodsdon'tcontainenough,andweneedsupplements.Fortunately,manyexcellentstudieshavenowresolvedtheissue.

slipah/Flickr

OnOctober10,2011,researchersfromtheUniversityofMinnesotafoundthatwomenwhotooksupplementalmultivitaminsdiedatrateshigherthanthosewhodidn't.Twodayslater,researchersfromtheClevelandClinicfoundthatmenwhotookvitaminEhadanincreasedriskofprostatecancer."It'sbeenatoughweekforvitamins,"saidCarrieGannofABCNews.

Thesefindingsweren'tnew.Sevenpreviousstudieshadalreadyshownthatvitaminsincreasedtheriskofcancerandheartdiseaseandshortenedlives.Still,in2012,morethanhalfofallAmericanstooksomeformofvitaminsupplements.Whatfewpeoplerealize,however,isthattheirfascinationwithvitaminscanbetracedbacktooneman.AmanwhowassospectacularlyrightthathewontwoNobelPrizesandsospectacularlywrongthathewasarguablytheworld'sgreatestquack.

WhenAlbertEinsteinwasaskedwhathethoughtofPauling'swork,heshruggedhisshoulders."Itwastoocomplicatedforme."

In1931,LinusPaulingpublishedapaperintheJournaloftheAmericanChemicalSociety titled"TheNatureoftheChemicalBond." Beforepublication,chemistsknewoftwotypesofchemicalbonds:

ionic,whereoneatomgivesupanelectrontoanother;andcovalent,whereatomsshareelectrons.Paulingarguedthat itwasn'tthatsimple--electronsharingwassomewherebetweenionicandcovalent.Pauling'sidearevolutionizedthefield,marryingquantumphysicswithchemistry.Hisconceptwassorevolutionaryinfactthatwhenthejournaleditorreceivedthemanuscript,hecouldn'tfindanyonequalifiedtoreviewit.WhenAlbertEinsteinwasaskedwhathethoughtofPauling'swork,heshruggedhisshoulders."Itwastoocomplicatedforme,"hesaid.

Forthissinglepaper,PaulingreceivedtheLangmuirPrizeasthemostoutstandingyoungchemistintheUnitedStates,becametheyoungestpersonelectedtotheNationalAcademyofSciences,wasmadeafullprofessoratCaltech,andwontheNobelPrizeinChemistry.Hewas30yearsold.

In1949,Paulingpublishedapaperin Science titled"SickleCellAnemia,aMolecularDisease."Atthetime,scientistsknewthathemoglobin（theproteininbloodthattransportsoxygen）crystallizedintheveinsofpeoplewithsickle-cellanemia,causingjointpain,bloodclots,anddeath.Buttheydidn'tknowwhy.Paulingwasthefirsttoshowthatsicklehemoglobinhadaslightlydifferentelectricalcharge--aqualitythatdramaticallyaffectedhowthehemoglobinreactedwithoxygen.Hisfindinggavebirthtothefieldofmolecularbiology.

In1951,Paulingpublishedapaperinthe Proceedingsofthe NationalAcademyofSciences titled"TheStructureofProteins." Scientistsknewthatproteinswerecomposedofaseriesof aminoacids.Paulingproposedthatproteinsalsohadasecondary structuredeterminedbyhowtheyfoldeduponthemselves.Hecalledoneconfigurationthealphahelix--laterusedbyJamesWatsonandFrancisCricktoexplainthestructureofDNA.

Atleast15studieshavenowshownthatvitaminCdoesn'ttreatthecommoncold.

In1961,Paulingcollectedbloodfromgorillas,chimpanzees,andmonkeysattheSanDiegoZoo.Hewantedtoseewhethermutationsinhemoglobincouldbeusedasakindofevolutionaryclock.Paulingshowedthathumanshaddivergedfromgorillasabout11millionyearsago,muchearlierthanscientistshadsuspected.Acolleaguelaterremarked,"Atonestrokeheunitedthefieldsofpaleontology,evolutionarybiology,andmolecularbiology."

Pauling'saccomplishmentsweren'tlimitedtoscience.Beginninginthe1950s--andforthenextfortyyears--hewastheworld'smostrecognizedpeaceactivist.PaulingopposedtheinternmentofJapaneseAmericansduringWorldWarII,declinedRobertOppenheimer'soffertoworkontheManhattanProject,stooduptoSenatorJosephMcCarthybyrefusingaloyaltyoath,opposednuclearproliferation,publiclydebatednuclear-armshawkslikeEdwardTeller,forcedthegovernmenttoadmitthatnuclearexplosionscoulddamagehumangenes,convincedotherNobelPrizewinnerstoopposetheVietnamWar,andwrotethebest-sellingbook NoMoreWar!

 Pauling'seffortsledtotheNuclearTestBanTreaty.In1962,hewontheNobelPeacePrize--thefirstpersonevertowintwounsharedNobelPrizes.

InadditiontohiselectiontotheNationalAcademyofSciences,twoNobelPrizes,theNationalMedalofScience,andtheMedalforMerit（whichwasawardedbythepresidentoftheUnitedStates）,PaulingreceivedhonorarydegreesfromCambridgeUniversity,theUniversityofLondon,andtheUniversityofParis.In1961,heappearedonthecoverof Time magazine'sMenoftheYearissue,hailedasoneofthegreatestscientistswhohadeverlived.

Thenalltherigor,hardwork,andhardthinkingthathadmadeLinusPaulingalegenddisappeared.Inthewordsofacolleague,his"fallwasasgreatasanyclassictragedy."

"HewrotethatifIfollowedhisrecommendationoftaking3,000milligramsofvitaminC,Iwouldlivenotonly25yearslonger,butprobablymore."

TheturningpointcameinMarch1966,whenPaulingwas65yearsold.HehadjustreceivedtheCarlNeubergMedal."DuringatalkinNewYorkCity,"recalledPauling,"ImentionedhowmuchpleasureItookinreadingaboutthediscoveriesmadebyscientistsintheirvariousinvestigationsofthenatureoftheworld,andstatedthatIhopedIcouldliveanothertwenty-fiveyearsinordertocontinuetohavethispleasure.OnmyreturntoCaliforniaIreceivedaletterfromabiochemist,IrwinStone,whohadbeenatthetalk.HewrotethatifIfollowedhisrecommendationoftaking3,000milligramsofvitaminC,Iwouldlivenotonly25yearslonger,butprobablymore."Stone,whoreferredtohimselfasDr.Stone,hadspenttwoyearsstudyingchemistryincollege.Later,hereceivedanhonorarydegreefromtheLosAngelesCollegeofChiropracticanda"PhD"fromDonsbachUniversity,anon-accreditedcorrespondenceschoolinSouthernCalifornia.

PaulingfollowedStone'sadvice."Ibegantofeellivelierandhealthier,"hesaid."Inparticular,theseverecoldsIhadsufferedseveraltimesayearallmylifenolongeroccurred.Afterafewyears,IincreasedmyintakeofvitaminCtotentimes,thentwentytimes,andthenthreehundredtimestheRDA:

now18,000milligramsperday."

Fromthatdayforward,peoplewouldrememberLinusPaulingforonething:

vitaminC.

In1970,Paulingpublished VitaminCandtheCommonCold,urgingthepublictotake3,000milligramsofvitaminCeveryday（about50timestherecommendeddailyallowance）.Paulingbelievedthatthecommoncoldwouldsoonbeahistoricalfootnote."Itwilltakedecadestoeradicatethecommoncoldcompletely,"hewrote,"butitcan,Ibelieve,becontrolledentirelyintheUnitedStatesandsomeothercountrieswithinafewyears.Ilookforwardtowitnessingthissteptowardabetterworld."Pauling'sbookbecameaninstantbestseller.Paperbackversionswereprintedin1971and1973,andanexpandededitiontitled VitaminC,theCommonColdandtheFlu,publishedthreeyearslater,promisedtowardoffapredictedswineflupandemic.SalesofvitaminCdoubled,tripled,andquadrupled.Drugstorescouldn'tkeepupwithdemand.Bythemid-1970s,50millionAmericanswerefollowingPauling'sadvice.Vitaminmanufacturerscalledit"theLinusPaulingeffect."

Scientistsweren'tasenthusiastic.OnDecember14,1942,aboutthirtyyearsbeforePaulingpublishedhisfirstbook,DonaldCowan,HaroldDiehl,andAbeBaker,fromtheUniversityofMinnesota,publishedapaperinthe JournaloftheAmerican MedicalAssociation titled"VitaminsforthePreventionofColds."Theauthorsconcluded,"Undertheconditionsofthiscontrolledstudy,inwhich980coldsweretreated...thereisnoindicationthatvitaminCalone,anantihistaminealone,orvitaminCplusanantihistaminehaveanyimportanteffectonthedurationorseverityofinfectionsoftheupperrespiratorytract."

Whenheoccasionallyappearedbeforethemediawithobviouscoldsymptoms,hesaidhewassufferingfromallergies.

Otherstudiesfollowed.AfterPauling'spronouncement,researchersattheUniversityofMarylandgave3,000milligramsofvitaminCeverydayforthreeweekstoelevenvolunteersandasugarpill（placebo）totenothers.Thentheyinfectedvolunteerswithacommoncoldvirus.Alldevelopedcoldsymptomsofsimilarduration.AttheUniversityofToronto,researchersadministeredvitaminCorplaceboto3,500volunteers.Again,vitaminCdidn'tpreventcolds,eveninthosereceivingasmuchas2,000milligramsaday.In2002,researchersintheNetherlandsadministeredmultivitaminsorplacebotomorethan600volunteers.Again,nodifference.Atleast15studieshavenowshownthatvitaminCdoesn'ttreatthecommoncold.Asaconsequence,neithertheFDA,theAmericanAcademyofPediatrics,theAmericanMedicalAssociation,theAmericanDieteticAssociation,theCenterforHumanNutritionattheJohnsHopkinsBloombergSchoolofPublicHealth,northeDepartmentofHealthandHumanServicesrecommendsupplementalvitaminCforthepreventionortreatmentofcolds.

Althoughstudyafterstudyshowedthathewaswrong,Paulingrefusedtobelieveit,continuingtopromotevitaminCinspeeches,populararticles,andbooks.Whenheoccasionallyappearedbeforethemediawithobviouscoldsymptoms,hesaidhewassufferingfromallergies.

ThenLinusPaulinguppedthe