Coffee%Intake%&%Hydration%Status%12/07/18%%Research%Review%

Ashley%Aegerter%

UWGB%Dietetic%Internship%18H19%

Outline%

1.  Background%

2.  Personal%Interest%

3.  Why%should%we%care%about%this%subject?%

4.  3%Research%Studies%

5.  Take%Home%Messages%

Background%

! Caffeine:%%a%white,%crystalline,%

bitter,%alkaloid,%usually%

derived%from%coffee%or%

tea,%used%in%medicine%as%

a%NS%stimulant%

Definition%of%CAFFEINE.%(2018).%Retrieved%from%https://www.merriamHwebster.com/dictionary/caffeine%

Caffeine%Formula.%(2018).%Retrieved%from%http://www.softschools.com/formulas/chemistry/caffeine_formula/465/%

Background%–%Typical%Caffeine%Content%

Coffee drinks Size in oz. Caffeine (mg)

Brewed 8 oz. 95-165 mg

Espresso 1 oz. 47-64 mg

Espresso, decaf 1 0

Instant 8 63

Brewed, decaf 8 2-5

Latte or mocha 8 63-126

Caffeine%content%for%coffee,%tea,%soda%and%more.%(2018).%Retrieved%from%https://www.mayoclinic.org/healthyHlifestyle/nutritionHandHhealthyHeating/inHdepth/caffeine/artH20049372%

Background%

! Dehydration:%when%the%body%uses%or%loses%more%fluid%than%

taken%in,%and%doesn't%have%enough%water%and%other%fluids%to%

carry%out%its%normal%functions%

!  Total%body%water%(TBW)%%

! Males: 2.447 - 0.09156(age(years)) + 0.1074(height(cm)) + 0.3362(weight(kg))

! Females: -2.097 + 0.1069(height(cm)) + 0.2466(weight(kg))

Total%Body%Water%(Watson%Formula)%|%Calculate%by%QxMD.%(2018).%Retrieved%from%https://qxmd.com/calculate/calculator_344/totalHbodyHwaterHwatsonHformula%

%Water%and%hydration:%Physiological%basis%in%Adults.%(2018).%Retrieved%from%https://www.h4hinitiative.com/book/print/68%

Distribution**of**TBW**among**compartments:%

Personal%Interest%

1.  I%love%coffee!%%Is%it%dehydrating%me?%

2.  Coffee%intake%among%%

MNT%&%LTC%patients%%

•  Coffee%intake%

•  Coffee%restrictions%

•  The%impact%on%their%

health%Photo:%Coffee%Scientists%Find%an%Optimal%Number%of%Cups%for%a%Healthy%Heart.%(2018).%Retrieved%from%https://www.inverse.com/

article/46253HcoffeeHheartHhealthHcaffeine%

Why should we care?

Healthy%adul

t%

body%~60%

%

body%weight%

%

Perlman,%H.%(2018).%Water%properties:%The%water%in%you%(Water%Science%School).%Retrieved%from%https://water.usgs.gov/edu/propertyyou.html%

Why%we%should%care!%

! Document%fluid%intake%

! Assess%hydration%status%

! Impact%of%coffee%on:%

! %total%body%water%%

(TBW%)%

! hydration%status%

!  We%as%RD’s%need%to%document%fluid%intake%and%hydration%status%

! what%to%include%

! Is%coffee%actually%adding%to%the%total?%%

!  Impact%of%coffee%on:%

!  %total%body%water%(TBW%)%

! hydration%status%

Ann,%M.%(2018).%How%Many%Milligrams%of%Caffeine%Are%in%a%Cup%of%Coffee?.%Retrieved%from%https://www.livestrong.com/article/

260763HhowHmanyHmilligramsHofHcaffeineHareHinHaHcupHofHcoffee/%

Do%I%have%to%drink%eight%glasses%of%water%every%day?.%(2018).%Retrieved%from%https://

coach.nine.com.au/2018/04/13/11/05/eightHglassesHofHwaterHaHdayHexpertHverdict%

No%Evidence%of%Dehydration%with%

Moderate%Daily%Coffee%Intake,%

2014%PLOS%ONE%

Sophie%C.%Killer%et%al.%

Study%1%

Study%1:%%

Dehydration%with%Moderate%Daily%Coffee%Intake,%%

PLOS%ONE,%Killer,%Sophie%C.%et%al.,%2014%

! Research%Purpose:%Directly%compare%

effects%of%coffee%vs.%water%intake%using%a%

range%of%validated%hydration%

assessments%

! Type%of%Study:%! Counterbalanced%CrossHOver%trial%

! Class%C%Study%1:%Dehydration%with%Moderate%Daily%Coffee%Intake,%PLOS%ONE,%Killer,%Sophie%C.%et%al.,%2014%

Study%1:%%

Dehydration%with%Moderate%Daily%Coffee%Intake,%%

PLOS%ONE,%Killer,%Sophie%C.%et%al.,%2014%

! Participation:%!  50%Men%aged%18H50%years%

! Moderate%coffee%drinkers%(3H6)%

! NOT%on%specific%medications%

!  Free%from%chronic%illness%

! Measurements:%%

! Daily*urinary*measures**! Hematological*hydration*markers*! Body*Mass*(BM)%&%Total*body*water*(TBW)%%

!  Plasma%analyzed%for%caffeine%Study%1:%Dehydration%with%Moderate%Daily%Coffee%Intake,%PLOS%ONE,%Killer,%Sophie%C.%et%al.,%2014%

Study%1:%%

Dehydration%with%Moderate%Daily%Coffee%Intake,%%

PLOS%ONE,%Killer,%Sophie%C.%et%al.,%2014%

!  University%of%Birmingham%

!  Two%visits%prior%to%testing%

!  Education%on%diet%diary,%turn%in%diary,%baseline%body%weights%

!  Two%trials%

!  4%days%each:%TuesdayHFriday%during%FebruaryHDecember%

!  Separated%by%10%day%washHout%

!  Two%treatment%groups:%

!  Coffee%trial%(C)=%%%800mL/%day%%%%(4mg/%kg)%

!  Water%%trial%(W)=%%%800mL/%day%

Study%1:%Dehydration%with%Moderate%Daily%Coffee%Intake,%PLOS%ONE,%Killer,%Sophie%C.%et%al.,%2014%

Design:*

Study%1:%%

Dehydration%with%Moderate%Daily%Coffee%Intake,%%

PLOS%ONE,%Killer,%Sophie%C.%et%al.,%2014%

Design%Continued:%

Study%1:%Dehydration%with%Moderate%Daily%Coffee%Intake,%PLOS%ONE,%Killer,%Sophie%C.%et%al.,%2014%

Study%1:%%Dehydration%with%Moderate%Daily%Coffee%Intake,%PLOS%ONE,%Killer,%Sophie%C.%et%al.,%2014%

Statistical*Analysis:*

%%%%%%%

1.  TBW%p=0.90%

2. Body%Mass%p=0.45%

3. Urine%void%volume%p=0.86%

4.   *24*hour*urine*collection:*

%%%%%%%%

Study%1:%%

Dehydration%with%Moderate%Daily%Coffee%Intake,%%

PLOS%ONE,%Killer,%Sophie%C.%et%al.,%2014%

! Findings:%%! No%significant%differences:%BM,%TBW,%UV,%Blood%tests%

! 4mg/kg%is%not%dehydrating%

! Maintained%stable%fluid%balance%

! Coffee%contributed%to%daily%fluid%requirements%

! Overall%quality%rating:%+%%

Study%1:%Dehydration%with%Moderate%Daily%Coffee%Intake,%PLOS%ONE,%Killer,%Sophie%C.%et%al.,%2014%

Study%1:%%

Dehydration%with%Moderate%Daily%Coffee%Intake,%%

PLOS%ONE,%Killer,%Sophie%C.%et%al.,%2014%

! Strengths:%%! Validated%measurements%&%tests%

! Diet%and%exercise%was%controlled%

! Coffee%trial%was%4mg/kg/day%

! Limitations%of%the%study:%

! FreeHliving%population%! Only%male%participants%

Study%1:%Dehydration%with%Moderate%Daily%Coffee%Intake,%PLOS%ONE,%Killer,%Sophie%C.%et%al.,%2014%

%

Coffee%with%High%but%Not%Low%

Caffeine%Content%Augments%Fluid%and%

Electrolyte%Excretion%at%Rest,%2017%%Frontiers%in%Nutrition%%

Adam%D.%Seal%et.%Al.%

Study%2%

Study%2:%

Coffee%with%High%vs.%Low%Caffeine%Content,%%

Frontiers%in%Nutrition,%Adam%D.%Seal%et.%al.,%2017%

! Research%Purpose:%%examine%effect%of%low%vs.%high%levels%of%caffeine,%via$coffee,%on%fluid%balance%in%habitual%coffee%drinkers%at%rest.%%!  Three%treatment%groups:%

!  200%mL%of%W%

!  200%mL%LCAF%(3%mg/kg)%

!  200%mL%HCAF%(6%mg/%kg)%

! Type%of%Study:%! Counterbalanced%CrossHover%%! Class%C%

Study%2:%Coffee%with%High%vs.%Low%Caffeine%Content,%Frontiers%in%Nutrition,%Adam%D.%Seal%et.%al.,%2017%

Study%2:%

Coffee%with%High%vs.%Low%Caffeine%Content,%%

Frontiers%in%Nutrition,%Adam%D.%Seal%et.%al.,%2017%

! Participation:%! 10%total%(8%men,%2%women)%%

! Aged%22H32%years%! Habitual%coffee%drinkers%(1H3%cups%per%day)%

! Measurements:%%

! Urine%samples%collected%60,120,%and%180%min%%%

! Urine%volume%(UV)%

! Urine%osmolality%(UOsm)%

! Na+,%K+%%Study%2:%Coffee%with%High%vs.%Low%Caffeine%Content,%Frontiers%in%Nutrition,%Adam%D.%Seal%et.%al.,%2017%

Study%2:%

Coffee%with%High%vs.%Low%Caffeine%Content,%%

Frontiers%in%Nutrition,%Adam%D.%Seal%et.%al.,%2017%

Design:%

! 3%trails%each%1%day%long%H>%5%day%“break%period”%

! Over%night%fast%before%providing%a%urine%sample%(time=0%min)%

! They%consumed%a%standard%breakfast%&%assigned%treatment%

! After%treatment%participants%rested%in%laboratory%for%3%h%%

! Urine%was%collected%&%tested%%(time=60,%120,%&%180%min)%

Study%2:%Coffee%with%High%vs.%Low%Caffeine%Content,%Frontiers%in%Nutrition,%Adam%D.%Seal%et.%al.,%2017%

a=%statistically%significant%difference%from%water%b=%statistically%significant%difference%from%LCAF%

Urine%Volume%and%electrolyte%excretion%during%the%water%(W),%LCAF%(3%mg/kg),%HCAF%(6%mg/kg)%

Study%2:%Coffee%with%High%vs.%Low%Caffeine%Content,%Frontiers%in%Nutrition,%Adam%D.%Seal%et.%al.,%2017%

min*

UV%

U(Na+)%

a=%statistically%significant%difference%from%water%

b=%statistically%significant%difference%from%LCAF%

Urine%Volume%and%electrolyte%excretion%during%the%water%(W),%LCAF%(3%mg/kg),%HCAF%(6%mg/kg)%

Study%2:%%Coffee%with%High%vs.%Low%Caffeine%Content,%%Frontiers%in%Nutrition,%Adam%D.%Seal%et.%al.,%2017%

Study%2:%Coffee%with%High%vs.%Low%Caffeine%Content,%%

Frontiers%in%Nutrition,%Adam%D.%Seal%et.%al.,%2017%

! Findings:%%! High%caffeine%intake%(6%mg/kg)%%

! Acute%diuretic%effect%represented%by%increased%UV%at%time=%60,%120%&%180%min%%after%ingestion%

! Water%&%Moderate%dose%(3%mg/kg)%%%

! No%acute%diuretic%effect%

! Overall%quality%rating:%+%%

Study%2:%Coffee%with%High%vs.%Low%Caffeine%Content,%Frontiers%in%Nutrition,%Adam%D.%Seal%et.%al.,%2017%

Study%2:%Coffee%with%High%vs.%Low%Caffeine%Content,%%

Frontiers%in%Nutrition,%Adam%D.%Seal%et.%al.,%2017%

! Strengths:%%! Used%three%variables%(W,%LCAF,%HCAF)%

o  Used%coffee%rather%than%caffeine%tablets%o  Caffeine%relative%to%body%weight%

! Limitations%of%the%study:%

! Mostly%men%

! Small%sample%size%

! Only%measured%acute%diuretic%effect%

Study%2:%Coffee%with%High%vs.%Low%Caffeine%Content,%Frontiers%in%Nutrition,%Adam%D.%Seal%et.%al.,%2017%

%

Caffeine%and%Diuresis%During%

Rest%and%Exercise,%2014%%Elsevier%Inc.%

Yang%Zhang%et%al.%

Study%3%

Study%3:%

Caffeine%And%Diuresis%During%Rest%And%Exercise,%%

Elsevier%Inc.,%Zhang,%Yang%et%al.,%2014%

! Research%Purpose:%%the%objective%of%this%metaHanalysis%was%to%quantify%caffeine%induced%diuresis%in%adults%during%rest%and%exercise.%%

! %Type%of%Study:%! MetaHAnalysis%

! Class%M%

Study%3:%Caffeine%And%Diuresis%During%Rest%And%Exercise,%Elsevier%Inc.,%Zhang,%Yang%et%al.%2014%

Study%3:%

Caffeine%And%Diuresis%During%Rest%And%Exercise,%%

Elsevier%Inc.,%Zhang,%Yang%et%al.,%2014%

!  Participation:%!  Studies%included:%%

!  Healthy%adults%!  Sufficient%info%on%caffeine%effect%size%(ES)%on%urine%volume%

(UV)%

!  16%studies%provided%28%usable%investigations%%!  379%participants%(246%male,%133%female)%

! Measurements:%%

!  ES:%Caffeine%%vs.%nonHcaffeine%

Study%3:%Caffeine%And%Diuresis%During%Rest%And%Exercise,%Elsevier%Inc.,%Zhang,%Yang%et%al.%2014%

•  <%0.20%ES=%trivial%

•  0.20H0.49%ES=%small%

•  0.50H0.79%ES=%moderate%

•  0.80%or%<%ES=%large%

Study%3:%

Caffeine%And%Diuresis%During%Rest%And%Exercise,%%

Elsevier%Inc.,%Zhang,%Yang%et%al.,%2014%

Design*Averages:*

! Sufficient%info%on%ES%

! Calculation,%monitor%and%review%of%ES’s%

! UV%following%caffeine%ingestion%

! Moderators%potentially%effecting%diuresis%

! Dosage%&%duration%

Study%3:%Caffeine%And%Diuresis%During%Rest%And%Exercise,%Elsevier%Inc.,%Zhang,%Yang%et%al.%2014%

Study%3:Caffeine%And%Diuresis%During%Rest%And%Exercise,%%

Elsevier%Inc.,%Zhang,%Yang%et%al.%2014%

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

=28

Study%3:%

Caffeine%And%Diuresis%During%Rest%And%Exercise,%%

Elsevier%Inc.,%Zhang,%Yang%et%al.,%2014%

! Findings:%%! Diuresis%was%small%(ES=0.29)%

!  females%(ES=0.75)%vs.%males%(ES=0.13)%

! Fluid%loss%associated%with%caffeine%was%

unwarranted%particularly%when%intake%precedes%

exercise%

!  (ES=0.10)%

! Overall%quality%rating:%+%

Study%3:%Caffeine%And%Diuresis%During%Rest%And%Exercise,%Elsevier%Inc.,%Zhang,%Yang%et%al.%2014%

Study%3:%

Caffeine%And%Diuresis%During%Rest%And%Exercise,%%

Elsevier%Inc.,%Zhang,%Yang%et%al.,%2014%

! Strengths:%%! MetaHanalysis%(16%studies=%28%investigations)%

! Solid%inclusion/exclusion%! Assessment%for%risk%of%Bias:%Physiotherapy%EvidenceH

Based%Database%Scale%(PEDro)%%

! ES%was%determined%sufficient%

! Limitations%of%the%study:%

! MetaHanalysis%(class:%M)%

! Some%used%caffeine%pills%

Study%3:%Caffeine%And%Diuresis%During%Rest%And%Exercise,%Elsevier%Inc.,%Zhang,%Yang%et%al.%2014%

Conclusion%Coffee%Intake%&%Hydration%Status%%

Further%Questions%

! These%studies%were%done%on%healthy%individuals%

! Critically%ill%patients%

! Patients%on%dialysis%

! Observational%studies:%critically%ill%&%dialysis%

! LongerHterm%study%

Research%Review%Findings%

1.  TBW%&%UV%were%not%affected,%coffee%was%

not%dehydrating%

2.  Acute%diuretic%effect%6%mg/%kg%%

3.  Men%may%experience%less%diuresis%than%

women,%caffeine%with%exercise%≠%diuresis%%

Take%Home%Message%

! Moderate%coffee%intake%will%not%effect%

hydration%status%on…%

! Healthy%individuals%

! Habitual%coffee%drinkers%

! People%participating%in%exercise%

! Coffee%should%be%counted%in%fluid%intake%

%

References%

!  Study*1:*Killer,%Sophie%C.%et%al.%"No%Evidence%Of%Dehydration%With%Moderate%Daily%Coffee%Intake:%A%Counterbalanced%CrossHOver%Study%In%A%FreeHLiving%Population".%Plos$ONE,%vol%9,%no.%1,%2014,%p.%e84154.%Public$Library$Of$Science$(Plos),%doi:10.1371/journal.pone.0084154.%

!  Study*2:*Seal,%Adam%D.%et%al.%"Coffee%With%High%But%Not%Low%Caffeine%Content%Augments%Fluid%And%Electrolyte%Excretion%At%Rest".%Frontiers$In$Nutrition,%vol%4,%2017.%Frontiers$Media$SA,%doi:10.3389/fnut.2017.00040.%

!  Study*3:**Zhang,%Yang%et%al.%"Caffeine%And%Diuresis%During%Rest%And%Exercise:%A%MetaHAnalysis".%Journal$Of$Science$And$Medicine$In$Sport,%vol%18,%no.%5,%2015,%pp.%569H574.%Elsevier$BV,%doi:10.1016/j.jsams.2014.07.017.%

!  Other*References:%

!  Do%I%have%to%drink%eight%glasses%of%water%every%day?.%(2018).%Retrieved%from%https://coach.nine.com.au/2018/04/13/11/05/eightHglassesHofHwaterHaHdayHexpertHverdict%

!  Ann,%M.%(2018).%How%Many%Milligrams%of%Caffeine%Are%in%a%Cup%of%Coffee?.%Retrieved%from%https://www.livestrong.com/article/260763HhowHmanyHmilligramsHofHcaffeineHareHinHaHcupHofHcoffee/%

!  Perlman,%H.%(2018).%Water%properties:%The%water%in%you%(Water%Science%School).%Retrieved%from%https://water.usgs.gov/edu/propertyyou.html%

!  %Water%and%hydration:%Physiological%basis%in%Adults.%(2018).%Retrieved%from%https://www.h4hinitiative.com/book/print/68%

!  Total%Body%Water%(Watson%Formula)%|%Calculate%by%QxMD.%(2018).%Retrieved%from%https://qxmd.com/calculate/calculator_344/totalHbodyHwaterHwatsonHformula%

!  Caffeine%content%for%coffee,%tea,%soda%and%more.%(2018).%Retrieved%from%https://www.mayoclinic.org/healthyHlifestyle/nutritionHandHhealthyHeating/inHdepth/caffeine/artH20049372%

!  Definition%of%CAFFEINE.%(2018).%Retrieved%from%https://www.merriamHwebster.com/dictionary/caffeine%

!  Caffeine%Formula.%(2018).%Retrieved%from%http://www.softschools.com/formulas/chemistry/caffeine_formula/465/%

%

Thank*you*Coffee%Intake%&%Hydration%Status%%

Ashley%Aegerter%

uwgbresearchreviews.weebly.com*