What Really Causes Acid Reflux and GERD.docx

What Really Causes Acid Reflux and GERD.docx

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WhatReallyCausesAcidRefluxandGERD

WhatReallyCausesAcidRefluxandGERD?

ThisisthefirstarticleofafourpartseriesonacidrefluxandGERD.Readthe secondarticle onthemythsofH.pyloriandlowstomachacidbeingthemajorcauses,the thirdarticle onthemainstreammedicaltreatmentsandthe finalarticle onthemythsoftriggerfoodsandaGERDdietthatworkswithoutdrugs.

WhatisAcidRefluxandGERD?

AboutsixtymillionpeopleintheUSreportthattheysufferfrompainfulsymptomsofacidrefluxatleastonceaweek.Heartburn,abdominalpain,cough,regurgitation,sourtasteinthemouth,sorethroat,hoarseness,laryngitis,asthma-likesymptomsandsinusirritationarethetypicalsymptoms.Smoking,pregnancy,obesity, hiatalhernia  andeventight-fittingclothescanmakethesesymptomsworse.

Acidrefluxoccurswhenacidandothercontentsofthestomachescapeintotheesophagusandbeyond.Chronicacidrefluxisoftenassociatedwithdamagebecausetheesophagusandotheraffectedtissuesarenotprotectedbythethickmucuslayerthatcoatstheinsideofthestomach.And,theresultispainfulirritationwhichcanleadto esophagitis, and Barrett’sesophagus,even esophagealcancer.

Persistentdamagingrefluxisreferredtoasgastroesophagealrefluxdisease（GERD）. Acidrefluxmayalsocausesevereirritationofthevocalcords,aconditionreferredtoaslaryngopharyngealreflux（LPR）.

MyStory

Formethissubjectispersonal.Iamoneofthesixtymillionpeople.Isufferedwithacidrefluxforagoodpartofmyadultlife.Ineverunderstoodwhatcausedit.Ionlyknewthatmyconstantheartburnandregurgitationsymptomsinterferedwithmywork,mysleepandmygeneralwellbeing. Myconditioncontinuedtogetworseleadingtoanyone’snightmare.

Iawokeinthemiddleofthenightandleaptoutofbedstillhalfdreaming,thinking“Ohmygod,thisiswhatitfeelsliketodie.”Icouldn’tbreathe;Iwaschokingforairandmylungsfeltliketheywerefilledwithburningliquid.Irantothebathroomcoughingupsomethingfrommylungsthatsimplydidnotregister.Itfeltlikeacidwasfillingmylungs.IsoonrealizedthatIhadsufferedsevereacidreflux;stomachacidthattraveledupmyesophagusuntilIaspirateditintomylungs.Iwillneverforgetthatmoment. ItdefinedthekindoffearandsufferingthatispossiblewithGERD.

Likemanypeoplewiththiscondition,Irecognizedthatmysituationwasbecomingserious.Buttherecommendedmedicines–antacids,H2blockersandevenPPIdrugsdidnotgivemeadequatereliefandInevernoticedanydietarypatternthatimprovedmysymptoms.Butthatallchangedin2004.

Ontheadviceofmyolderson,apersonalfitnesstrainer,Idecidedtogoonalowcarb,highfatdiet（LCHFD）toloseafewpounds.Whathappenednextmademeforgetaboutweightloss,becausemyrefluxsymptomsvanishedtheverynextday.Icouldn’tbelieveit!

Whyhadnooneevertoldmeaboutthis?

Itturnsoutthatmostpeopledidn’tknoworwerejustfindingoutthemselves.ButthankstoGoogle,Isoonrealizedthatthiswasnofluke.Manyothersweresayingthesamethingand Drs.MikeandMaryDanEades hadwrittenaboutthisintheirbestsellingbook, ProteinPower. IalsofoundoutthatsomedoctorsatDukeUniversityhaddoneasmallclinicalstudyconfirmingthatcuttingcarbscanrelievesymptoms.

Whiletherevelationwasagreatrewardinandofitself,forthefirsttimeinmylifeIcouldcontrolmysymptoms,Iwasfarfromsatisfied.Ireallywantedtoknowwhy.Ifremovingmostcarbsstopsheartburn,didthatmeanthatcarbscausedheartburn?

Idecidedtogettothebottomofthingsandstarteddoingresearchonhoweachtypeoffood（fats,proteinsandcarbohydrates）isdigested.Ireadaboutandthoughtaboutthedigestiveprocess–chewing,salivaryamylaseforstarch,stomachacidandpepsinforproteinbreakdown,lipaseforfats,etc.And,asIstartedreadingaboutdigestioninthesmallintestine,alightbulbwentoffinvolvinggutbacteria.

Asamicrobiologist,Ihadgrownandstudiedawidevarietyofbacteriaforyearsingraduateschool.Ialsoworkedwithintestinalbacteriaduringapostdoc.atTufts.Whilemyfocuswasgenetics,weconstantlyneededtogrowenoughbacteriatoworkwith.And,Irecalledtwoimportanttraitsofintestinalbacteria:

1.Theygetthebulkoftheirenergyfromcarbohydrates

2.Mostofthemproducelotsofgas

Dependingonthestrain,bacteriaproducecopiousamountsofhydrogenandcarbondioxidegas.Also,intestinalArchaea,whichlooklikebacteriaunderthemicroscope,butareactuallyaseparatebranchoflife,produceathirdintestinalgas,methane.Carbohydratesarethebestfuelsourceforgasformation.AccordingtoSuarezandLevitt,[1]30gofcarbohydratethatescapesabsorptioninadaycouldproducemorethantenlitersofhydrogengasinsmallintestine.Imaginehowmuchpressurethisamountofgascancreate.Intestinalbacteriaproducesomuchgasthattherehavebeenwelldocumentedcasesofexplosionsduringintestinalsurgery.[2],[3] Thisgavemeanidea:

“WhatifsomeofthecarbsIhadbeeneatingwerenotbeingefficientlydigestedandabsorbedintomybloodsteam,andinsteadtheywerepersistinginmysmallintestine?

Wouldn’ttherebeachancethatmyacidrefluxwastheresultofintestinalgaspressurefromabloomofgas-producingbacteriafedbycarbohydrates?

I.e.mentos inacokebottle” 

Couldtheanswerbethatsimple?

Ineededtolearnmoreandfindoutifthisideawasfullofholes.And,Isetouttodestroymyowntheory:

）

 Whatwecanagreeon

ThefirstthingIdidwaslearnallIcouldaboutwhatotherscientiststhought.Onethingeveryoneseemedtoagreeonwasthatacidrefluxoccursbecausethegroupofmusclesatthetopofthestomachareunabletokeepthestomach’scontentsfromenteringtheesophagus.Thisgroupofmusclesiscalledtheloweresophagealsphincter（LES）.Thestomach’scontentsincludehydrochloricacid,bileanddigestiveenzymes.Butwhydoesacidrefluxoccur?

Accordingtothe NIH:

 “GERDresultswhentheloweresophagealsphincterorLESbecomesweakorrelaxeswhenitshouldnot,causingstomachcontentstoriseupintotheesophagus.”

LESrelaxationeventsarecalledtransientloweresophagealsphincterrelaxations（TLESRs）.TheLESappearstoundergotheserelaxationevents,evenwhenwearenotswallowing.BothLESpressureandTLESRscanbemeasuredbyatechniquecalledmanometry,whereapressure-sensitivetubeispasseddowntheesophagusthroughtheLES.Thistechniquehasbeenusedformanystudies[4],[5],[6] andclearlyshowthat GERDpatientsexhibit:

∙Moreepisodesofreflux

∙LessLESpressure

∙MorefrequentepisodesofTLESRs

∙MoreextensiverefluxduringTLESRs,particularlyaftermeals

∙Morepressureinthestomach（intragastricpressure）andmorebelching

Iwonderedifsomeoftheseideasmightdisprovemytheoryorweretheysomehowconsistentwithmyownobservations.Ithoughtabouteachobservationtoseeiftherewassomecommonthread.ThoughincreasedpressureinthestomachhadbeenwelldocumentedinGERDpatients,[7] noonehadagoodexplanationaboutwherethepressurewascomingfrom.But,mytheoryclearlyexplainedapotentialsource:

copiousamountsofgasandpressurefrombacterialfermentationinourintestines.

GotGas?

AsforlessLESpressure,youmightbeabletoimagineintragrastricpressure“forcing”theLEStoopenasapossiblemechanismofacidreflux.Clearlyifthisweretooccur,theLESpressuremeasurementwouldbereducedbytheintragastricgaspressure.InotherwordsreducedLESpressureinGERDpatientscanbeexplainedbymytheory.

ThesameanalogycanbeappliedtoexplainTLERsaswellasincreasedrefluxduringTLESRs.ThegaspressureforcingtheLEStoopenwouldbemeasuredasreducedLESpressureorrelaxationeventsbymanometryandbeexpectedtoincreasetheamountofrefluxateineachevent.ThiswouldbeparticularlytrueaftermealsifmalabsorbedcarbohydratesineachmealweredrivingthebacterialgrowthandgasproductionasIsuspected.Thus,mytheoryalsoexplainstheincreaseinTLERsinGERDpatients,particularlyaftermeals.

Whileonthesubjectofgaspressure,thereisonemoreimportantpredictionmytheorymakes.Ifyouweretostoptheprocessofrefluxandbelchingwithoutresolvingbacterialovergrowth,youmightexpectabuildupingaspressureinthestomachandsmallintestine.Onewaytolookatthisquestionistostudypeoplewhohavehadfundoplicationsurgery,wheretheLESissurgicallytightened,thuspreventingrefluxandbelching.ReportsonGERDpatientswhohaveundergonethisprocedureshowthattheysufferfromnewsymptomsincludingexcessivegas,flatulenceandbloating.[8],[9] TheprocedureisaimedatpreventingrefluxbytighteningtheLESmusclessurgically,butthesideeffectsareindicativeoftrappedstomachandintestinalgasaswouldbeexpectedwithuncontrolledmalabsorption,andexcessivebacterialfermentation.

Gotbacteria?

Essentially,Iwasproposingthatexcessdietarycarbscouldpromoteakindofgutdysbiosis（unbalancedgutmicrobiotawithtoomanygasproducingstrains）,possiblysmallintestinalbacterialovergrowth（SIBO）.Accordingtothisidea,acidrefluxoccursduetomicrobe-inducedgaspressure.AsIcontinuedmyresearch,Iwonderedwhattheworldmightlooklikeifmytheorywascorrect.ThefirstthingIfocusedonwasbacterialovergrowthitself.IreasonedthatyoushouldseeareductioninGERDsymptomswheneveryoureducedbacterialgrowthintheintestine.

Onewaytocontrolexcessivebacterialgrowthintheintestineistogoonalowcarbdiet,becausethistypeofdietlimitscarbohydratefuelthatbacterianeedforgrowth.AsImen