5
YOUCAN’TREALLY
SPEEDUPYOUR
METABOLISMFOR
WEIGHTLOSS
There’sa lotofhypearound‘speed-
ingupyourmetabolism’andlosing
weightbyexercisingmoretobuild
muscle,eatingdifferentfoodsor
takingsupplements.Butit’sa myth.
Whiletherearecertainfoods–
likecoffee,chilliandotherspices- thatmayincreasethebasalmet-
abolicratejustalittle,DrJensen
saysthechangeissonegligibleand
short-lived,itwouldneverhavean
impactonyourwaistline.
Buildingmoremuscles,however,
canbemorehelpful.Here’swhy:
oneofthevariablesthataffectsyour
restingmetabolicrateistheamount
ofleanbodymassyouhave.Atany
givenweight,themoremuscleon
yourbody,thehigheryourmetabol-
icrate.That’sbecausemuscleusesa
lotmoreenerg ythanfatwhileatrest.
Sothelogicis,ifyoucanbuildup
yourmuscle,you’llhaveahigher
restingmetabolismandwillburnthe
fuelinyourbodymorequickly.But
there’sa caveat.
Accordingtoprofessorofmedi-
cineMichaelRosenbaum,whostud-
iesweightlossandmetabolism:“If
youhavemoremuscle,itburnsfuel
morerapidly.Butthat’sonlyhalfthe
question.”If youdogainmoremuscle
andeffectivelyspeedupyourmetab-
olism,“Youhavetofightthenatural
tendency to [want to] eat moreasa
whysomefamilieshavehigheror
lowermetabolicrates).Genderalso
matters,sincewomenwithanygiven
bodycompositionandageburnfew-
erkilojoulesthancomparablemen.
Youcan’t easilymeasureyour
restingmetabolicrateina precise
way.Therearesomecommercially
availabletests,butthebestmeas-
urements come from research
studiesthatuseexpensiveequip-
ment.However,youcangeta rough
estimateofyourrestingmetabolic
ratebypluggingsomebasicvaria-
blesintoonlinecalculators,suchas
age,heightandweight.Thesewill
tellyouhowmanykilojoulesyou’re
expectedtoburneachday,andif
youeatthatmanyandyourweight
staysthesame,it’sprobablycorrect.4
ANOTHERTHING
THATSLOWSDOWN
THEMETABOLISM:
GETTINGOLDER
Theeffecthappensgradually,evenif
youhavethesameamountoffatand
muscletissue.Soifyou’re60,you’ll
burnfewerkilojoulesatrestthanyou
didwhenyouwere20.
DrJensensays thiscontinual
declinestartsinyoungadulthood- andwhythishappensisanother
metabolismquestionresearchers
haven’tanswered.“Whydoyouren-
erg yneedsgodownasyouage,even
ifyoukeepeverythingelsepretty
muchthesame?That’s one of the
biggermysteries.”
69
Eight Truths About How We Burn Kilojoules