Am J Clin Nutr 1993 Westerterp 759S 64S

8/3/2019 Am J Clin Nutr 1993 Westerterp 759S 64S

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I F rom the D ep ar tm en t o f H um an B io logy . U nivers ity o f L im bu rg .M aas trich t. T he N etherlands .

2 A ddress rep rin t req uests to K R W este rte rp . D epartm en t o f H um anB io logy . U niversity o f L im burg . P 0 B ox 616 .20 0 M D , M aastrich t.T he N eth erla nd s.

.In i J (l/ii \ zu ir 1993 :57(supp l):759S-6 5S . P rin ted in U SA . 199 3 A m erican Soc ie ty fo r C lin ica l N u tr ition 759S

Food quo tien t, re sp ira to ry quo tien t, and ene rgy ba lance1 2K laa s R H e .s ter ie rp

A BSTRA CT This pap er rev iew s ev idence tha t the m acro -n u trien t com po sition ofth e d ie t an d th e m ain tenance of energyba lan ce are corre la ted . In te rv en tio n s tud ies show th a t sub jec tslose w eigh t on low -fa t d ie ts and ga in w eigh t on h igh-fat d iets .D escrip tive stud ies show th at overw eigh t su b jects ea t re la tiv e lym o re fa t b u t have th e sam e to ta l energy in take as nonoverw eigh tsu b jec ts . T he body has a lim ited ab ility to ox id ize fa t com paredw ith its ab ility to ox id ize carb ohydrate an d pro te in . T he co n-e lusion is tha t becom ing overw eigh t can b e preven ted b y red uc in gthe fa t con ten t o f th e d ie t. S tud ies on n u trien t u tiliza tio n showa ready increase in carbohyd ra te o x ida tio n w hereas fa t ox ida tiondoes no t ch an ge afte r m ea ls en riched w ith , respec tive ly , ca rbo -h ydra te o r fa t. H ow ever, in th e lon g term , the resp ira to ry quo tien t(R Q ) is c lo ser to the food quo tien t (FQ ) for su b jec ts ea t in g h igh -fat d ie ts than it is fo r su b jects ea ting h ig h-ca rbohydra te d ie ts .F or h ig h-ca rbohydra te d iets , the RQ is low er than is th e FQ .ind ica ting th at sub jec ts m us t m obilize body fa t. T h is is su pportedby da ta on body w eigh t loss in sub jec ts ch ang ing from a s tan dardm ain tenance d ie t to a low -fa t d ie t, even w hile energy in take w asincreased w ith nearly 20% D irec t ev idence fo r a h igher energyexpend itu re fo r low -fa t d ie ts is no t y et ava ilab le . ..1 ,;i J (liiiNu tr I 993 :57(supp l) :759S-65S .KEY W ORD S Food quot ien t, re sp ira tory q uo t ien t, energyba lan ce, d ie ts, ca rbo hydra te , p ro te in . fat

In troduc t ionH um an s con sum e food to m ain ta in en ergy ba lan ce . F ood en-

e rgy is con sum ed in the fo rm ofcarbohydra te , p ro te in , and fa t,the m acronu trien ts o f ou r d ie t. T he d istribu tion o f food energybe tw een th e m acro nu trien ts d iffe rs be tw een cu ltu res and coun -trie s. T h ere is a fa irly w ide range of carbohydra te-p ro te in -fa tra tio s (c :p :f) a t w hich en ergy ba lance can be m ain ta ined . asshow n by na tionw ide stud ies o f nu trien t in tak e (T ab le). T h ecarboh ydra te in take rang es from 3 to 82 en% and the fa t in takeranges from 6 to 5 4 en# {176 }%w hereas the pro te in in take is a t leas t1 1 en% . W ith in one cu ltu re o r cou n try . d ie ta ry changes takep lace w ith chang es in foo d su pp ly . T here is an in creas ing av ail-ab ility o f fa ts in W este rn coun tries. In the U nited S ta tes thecon tribu tion of fa ts to th e d ie t has stead ily inc reased from 32en% in 1910 to 43 en% in 1985(F ig I ). T he sh ift in th e com -pos itio n of th e d ie t to a h ig her con tribu tion of fats h as o f tenbeen quo ted as th e reason fo r the inc reasing inc idence o f over-w eig h t. ie , o f a pos itiv e en ergy ba lance . T h is p ap er w ill d iscusssom e of reasons and ev idence fo r the co rre lation be tw een th em acronu tn ien t com pos ition ofthe d iet an d the m ain tenance o fenerg y ba lan ce.

D ie ta ry fa t-carbohydra te ra tio

E ne ig i b a lanceD ieta ry fa t is the m ain d ete rm inan t o f th e energy dens ity o

ou r d ie t. T he m etabo lizab le energy fo r d ieta ry carbohydra te .p ro te in . and fat is. respec tiv ely . 1 6 . 16 . and 37 kJ /g (3 ). F a t hasan im portan t fun ction as an energ y depo t in the bo dy as w ell.Fa t can be s to red w ith m in im al ad d ition al w eigh t. T h e en ergyd ensity o fthe fa t sto res is app rox im ate ly e igh t tim es h ig her thanis the energy d ensity o f th e carbohydra te (g lycogen) sto res (4 ).T hus . in m o st circum stances energ y ba lance can be reached w iththe m in im um bulk consum ing h igh-fa t d ie ts. an d an energ y sur-p lus is m ain ly sto red as body fat.

S om e s tu d ies show tha t p eo p le chang e energ y in take w h enthey change to a d iet w ith a low er o r a h ig her energy dens ity .D uncan e t a l (5) a llow ed sub jec ts to ea t to sa tie ty from a d ie tlow in energy dens ity (3 kJ /g ) and from a d ie t h igh in energyd ensity (6 .5 k J/g ). E ach d iet w as prov id ed fo r 5 d in a random izedcro ss -over des ign w ith a w eekend in be tw een . Sub jec ts ate nearlytw ice as m uch on the h igh-en ergy d iet (1 2 .5 M J/d ) , o r. con-verse ly . tw ice as little on the low -energy d ie t (6 .5 M J/d ). S ur-p ris ing ly . the re w as n o trend tow ard a h igher energy in take onsubseq uen t days on the low -energy d ie t o r to a low er energyin take on sub sequen t days o n the h igh-energ y d ie t. L issner e t a(6 ) p rov id ed su b jects w ith th ree d if fe ren t d ie ts. one w ith a low .on e w ith a m edium . and one w ith a h igh energy d en sityex ch an g ing carbohyd ra te and fat. A ll sub jec ts go t each d ie t fo14 d in a ba lanced sequen ce . E nergy in take increased fromm ean va lue of 8 .7 M J/d on the low -fa t d ie t ( 1 5-20 en% fa t)9 .8 M I/d on the m edium -fat d ie t (30-35 en% fa t) and to I 1M J/d on th e h ig h-fa t d ie t (45 -50 en% fa t). A ga in . th ere w as nsystem atic trend ofin take over tim e in any ofthe sub jec ts duringan y 14-d d ie ta ry trea tm en t. ind ica ting tha t the re w as no ad ap -ta tio n to the d ie t d uring the observa tion period . O n average ,sub jec ts w ere in energy ba lan ce on the m edium -fa t d ie t. lo sw eig h t on the low -fa t d ie t. and g ained w eig h t on the h igh-fa tdiet.

A nim als like th e labo ra to ry ra t com pen sa te in tim e ifthe en -e rg y dens ity o f the food is changed to ach iev e th e sam e energ yin take and reach the sam e hod w eigh t as con tro ls (7 ). T he fa ilu re


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* A dapted from reference I.

50

40

30

C

a)a)a)

0

C0

C00

.- - 4 - S.

20

10

01920 I 940 1 960 1 980

year

760S WESTERTERPTABLE 1Ratio of macronutrients in the die t o f people of different countries*

Country Carbohydrate Prote in Faten%

Nigeria 82 12 6Japan 77 12 11India 7 7 11 12CSSR 59 11 30U nited S tates 46 12 42Greenland 3 43 54

of humans to compensate for a change in the energ y density ofthe food may be a w ay fo r them to avo id becoming overw eight.Energy dilution w ith carbohydrate or fat analogues like aspar-tame (8 , 9 ) and sucrose po ly esthers has its application in thenew market for light products . On the other hand. there areindicatio ns that humans compensate for energ y dilutio n w hennot all high-energ y-dens ity food items are reduced-energy ver-s io ns by increas ing the consumption of nonmanipulated items(10 ). Subjects failed to compensate fo r increases in energ y intakeby cov ertly substituting part o fthe food items w ith high-energyversions.Obesiti

There are quite a few studies on the macronutrient ratio ofthe die t and obes ity o r be ing overw eight. Here w e restric t our-selves to s tudies w here subjects w ere allow ed to free ly choo sethe ir ow n foods under ordinary liv ing conditions . U nder thosec ircumstances , overw eight subjects take diets w ith a higher energydensity . Jiang and Hunt ( 1 1) asked 1 1 adult men to co llec t adouble portion of all they ate over 7 d for analy sis. The energydensity o f the diet, inc luding drinks, ranged from 1 .8 kJ/g innormal-w eight subjects to 3 .9 kJ/g in o verw eight subjects. S un-pris ing ly , the researchers mention that the energy density of thedie t in overw eight subjects w as not higher because of a higherfat content, and no alternative explanation is presented. D reonet al ( 1 2) related diet compos ition, as measured w ith 7 -d foodrecords , to body composition. as measured w ith hydrostaticw eighing , in 15 middle-ag ed men. Subjects w ith a higher per-centage body fat consumed a diet w ith re lativ ely more fat andless carbohydrate . Tremblay et al ( 1 3) performed a comparables tudy in 244 male adults, measuring diet compo sition w ith a 3-d food record. They also found that the en% fat o f the die t w aspos itiv ely co rre lated and the en% carbohydrate w as negative lycorrelated w ith the fatness o f the subjects . Finally , M iller e t al(14 ) made s im ilar observations in 2 16 adult subjects , 50% menand 50% w omen, and found that adipos ity w as positive ly con-re lated w ith die tary fat content and negative ly correlated w ithdie tary carbohydrate consumption. In all four studies mentionedabove ( 1 1 - I 4), there w as no correlation betw een energ y intakeand indexes for overw eight or obesity .

There hav e been indicatio ns that se lf-reported intake tends tobe an underestimate of true habitual intake . Repo rted intakestend to be low er than energy expenditure as measured s imul-taneous ly w ith doubly labe led w ater, espec ially in obese subjectsand subjects w ith a high energy intake . such as those engaged

in endurance exerc ise (1 5 , 1 6). W e do no t know w hether theresults o f those studies , mainly using se lf report to measure di-e tary intake . w ere influenced by this phenomenon. On the otherhand. it is nearly impossible to measure habitual intake w hilesubjects free ly choose the ir ow n foods under ordinary liv ingconditions w ith a more accurate alternative technique . Thedouble -portion technique as used by Jiang and Hunt ( 1 1 ) is oneo fthe best but is no t really feasible in large groups and interferesw ith daily routines w hen subjects are not at home every timethey eat something . Thus , Romieu et al1 7) and M iller (18)came to the conc lusion that the ro le o ffat intake in obes ity maybe independent o f energy intake .

Substr ate utilizatiouiKnow ing that obese subjects generally do no t eat more than

do normal-w eight subjects but do differ from normal-w eightsubjects w ith respect to the fat-carbohydrate ratio of the ir die t,the next question is. w hy is an isoenergetic die t fattening w henit contains re lative ly more fat and less carbohydrate? In termso fenergy , w e can make carbohydrate from prote in and fat fromcarbohydrate and thus fat and carbohydrate are not essentialnutrients . How ever the conversion processes are very energyconsuming and produce a lo t o fw aste products such as ammoniaand urea. Ideally . the body covers its energy needs w ith a mix tureo f fat and carbohydrate . S ome tissues preferentially use carbo -hydrate w hereas fat is less bulky to consume, as mentioned ear-her. A dditionally , humans are periodic eaters and continuousmetabo lizers ( ie . part o fthe energy intake is stored before usageas w ell).

The storage capac ities for fat and carbohydrate are very dif -ferent and this may have consequences for the regulationbody w eight. Flatt ( 1 9) proposed a model w ith a regulated car-bohydrate (g lycog en) s tore and w ith the fat s tore as a functio no f nutrient intake and nutrient utilization. A n increase in thefat content o f the die t needs an increase in fat o x idatio n andis hypothes ized that the latter needs an expans ion of the body-

FIG I D istribution of dietary energy intake betw een carbohydrate(H). prote in (#{ 149} ).nd fat (5 ) in the U nited S tates from 1910 to 1985(from ref 2 ) .


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FQ, RQ, AND ENERGY BALANCE 7 6 1 Sfat mass , explaining the increased adipos ity in subjects consum-i n g h i g h - f a t d i e t s .

S everal groups studied the effec t o fa chang e in nutrient intakeon nutrient utilization. N utrient utilization can be measuredw ith indirect calorimetry from oxygen consumption, carbondiox ide productio n, and urinary nitrogen excretion (20 ). S ome-tim es pro te in ox idation is measured by primed infus ion of a3C -labe led amino acid: measuring the e lim ination ofthe labelin respirato ry gas pro v ides a more rapid, more responsiv e index(2 1). S tudies o f nutrient utilization can be split in short-termstudies . usually measuring the effec ts o fa sing le meal, and long -term studies. covering at least one 24-h cyc le on a fixed die tw ith or w ithout an adaptation period befo rehand. The indirect-calorimetry system in short-term studies is a ventilated hood,w ith subjects ly ing or sitting . Long -term studies are performedin a respiration chamber that allow s subjects to mov e aroundon 10-20 m2 offloor space .

Sho rt-term studie s o f nutrient utilizatio nShort- term studies o f nutrient utilization are usually s tarted

in the postabsorptive condition after an overnight fast. Food isconsumed as a breakfast, after w hich base line measurementsand observations are continued for several hours . A cheson et al(22 ) measured the effec t o f a large carbohydrate meal (9 M i.Table 2 ) on nutrient utilizatio n. The high-carbohydrate loadlow ered the fat o x idation rate : how ever. there w ere no indicationsof the conv ersion of carbohydrate to fat. A ssuming completeprocessing o f the meal in the subsequent 10-h observatio n in-terval, the sto rage capacity for carbohydrate as g lycogen w asprobably suffic ient to accommodate the intake surplus becauseonly 1 33 g carbohydrate w as ox idized. In the ir nex t experiment.A cheson et al (23 ) contro lled the die t over the 3-6 d preceding

a tes t comparable to the one mentioned above . Subjects con-sumed a low -carbohydrate die t, a m ixed die t, or a high-carbo-hydrate die t. The higher the carbohydrate content o fthe initialdie t. the higher the carbohydrate ox idation rate after the car-b o h y d r a t e me a l : 1 7 7 5 . 2 4 1 1 1 , a n d 2 5 8 9 g o v e r t h e 1 4h after consumption o f 500 g in the low , medium , and highcarbohydrate g roup, respective ly . Carbohydrate o x idatio n w ashigher than it w as in the f irst experiment (2 2), possibly becauseo f the use of a different die tary carbohydrate. A gain, mostthe carbohydrate surplus w as stored as g lycog en, although therew as a s ig nificant lipid synthes is from carbohydrate of 3 .4 0 .6and 9 .0 1 .0 g in the medium- and high-carbohydrate g roups ,respectiv ely . How ev er. the lim ited lipogenes is combined w iththe extremely high carbohydrate intake w as judged to be un-impo rtant in daily life. Finally , Flatt e t al (24) s tudied the effec tso f the addition o f fat to a standard, m ixed m eal. Fat and carbohydrate ox idation w as not influenced by the increased faconsumption (Table 2). In the postabsorptive state the main fue lo f the body is fat (2 1, w ith a rapid shift to carbohydrate w henfeeding beg ins. independent of the fat content o f the fo od con-sumed.

Long-term studie s o f nutrient balanceObserv ations of nutrient balance should ideally cover at least

a 2 4-h interval o r a multiple o f 24 h because of the diurnalpattern of nutrient utilization (25). N ow adays . several labo ra-to ries hav e fac ilitie s such as respiration chambers to perfo rmthese s tudies. There have been at least fo ur studies on the con-sequences o f nutrient exchange for nutrient utilization as mea-sured over 24 h (Table 3 ).

Hunni Ct al (26) measured nutrient utilization in subjects con-suming a mix ed die t and. subsequently . a high-carbohydrate,

TA BLE 2Food intake and nutrient utilization

S tuds (re f) and c:p:f IntakeObservation

time

OxidationCarbohydrate

Rate Percent RateProtein

Percent R ateFat

PercentfI ji Ii g //i en% g/h en% g//z en%

A cheson et al (22)93:5:2 en% 9 .0 10 13 .3 6 6 2 .9 15 1 .7 19

A cheson et al (23)1 00:0 :0 e n 8 .4 14 12 .6 6 0 2 .6 12 2 .6 2 8l00:0:0enc 8 .4 14 17 .2 75 2 .4 II 1 .4 14100:0 :0 en 8 .4 14 18 .4 84 2 .4 1 1 0 .5 5

Flatt e t al. (2 4 )62:27:11 en 2 .0 9 9 .4 4 2 3 .1 14 4 .3 4 43 5 : l 5 : 5 0 e n c 3 . 6 9 9 . 4 4 1 2 . 8 1 2 4 . 6 4 735:15:50 en 3 .6 9 9 .4 40 3 .2 14 4 .7 46* Ca r h o hy dr a t e : p r o t e i n : f a t r a t i o .t D ex trin-maltose so lution flav ored w ith fruit juice.:t c :p:fdie t 3 -6 d preceding tes t. 14 :1 1 :7 5 en%. c:p:f die t 3 -6 d preceding tes t. 6 0 : 1 2 :2 8 enIIc:p:fdie t 3 -6 d preceding tes t. 80 :1 1:9 en%.# {1 8 2 }hree-quarters o f the fat in the form of medium-chain trig lycerides.


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7 6 2 S WESTERTERPTA BLE 3M ean 24-h food quo tien t (FQ ) and resp ira to ry q uo tien t (RQ ) fo r d ie tsw ith d ifferen t ca rbo hydra te :p ro te in :fa t ra tios (c :p :f ) from fo ur stud ies

S tudy (ref )and c:p :f

Dura t ionofd ie t

Energyb a lance FQ RQ

d .41J /d26

44 : 16 :4 0 en% 7 - 1 .4 0 .4 0 .85 0 .80 0 .0 1 78:16 :6 en% 7 -1 .9 0 .5 0 .9 5 0 .88 0 .01*

2845 :15 :4 0 en% 0 -0 .1 0 .85 0 .8 2 0 .0182:15 :3 en% 0 -0 .1 0 .96 0 .87 0 .01

2943:15 :42 en% 5-43 -0 .3 0 .3 0 .83 0 .84 0 .0165 :15 :2 0 en% 6-32 -0 .1 0 .2 0 .91 0 .88 0 .0 11

3020 :20 :60 en% 3 - 0 .7 7 0 .7 5 0 .0120 :20 :60 en% 7 - 0 .7 7 0 .7 5 0 .0135 :20 :45 en% 3 - 0 .8 3 0 .7 9 0 .0135 :2 0 :45 er i% 7 - 0 .83 0 .78 0 .0060 :20 :2 0 en% 3 - 0 .92 0 .86 0 .0260 :20 :2 0 en% 7 - 0 .9 2 0 .8 6 0 .01*t S ign ifican tly d iffe ren t from FQ : P < 0 .05 , tP < 0 .001 .

low -fa t d iet. B o th d iets w ere con sum ed for 7 d , w ith a 2-w kw ash ou t period in be tw een , and m easurem en ts o f nu trien t u ti-lization took p lace on the las t day of each 7-d p er io d . U nfor-tun a te ly . sub jec ts w ere in nega tive en ergy ba lance : in take w aso n average 14% low er than expend itu re dur in g the 24-h resp i-ration -ch am ber m easu rem en ts . D esp ite the n ega tive energ y ba l-an ce , ca rbohydra te and pro te in ox ida tio ns w ere low er than the irin take , even on the m ix ed d ie t. H ow ev er , these resu lts a re s tillw ith in the erro r ran ge o f th e ap p lied m ethod s (27 ). Th e carbo -hy dra te ox id ation m ore than doub led on the h ig h-ca rbohydra ted ie t com pared w ith the low -carbo hydra te d ie t. illu s trating theflex ib ility o fthe b ody to use carboh ydra te fo r energy m etab o lism .

L ean an d Jam es (28 ) m easured the m etabo lic e ffec t o fan iso -energe tic exchan ge of nu trien ts over one 24 -h in te rva l a fte r theconsum ption of a standard even ing m eal. S ub jec ts w ere m ea-su red fasting and , su bsequ en tly , a fte r a low -fa t d ie t and a h igh-fat d ie t. M ean energy in tak e , based o n 24 -h fasting energy ex-p end itu re p lus 5% , w as 1 .7% high er than w as m ean energy ex-p end itu re , w ith ind iv id ua l d iffe rences a ll 10% (ie , sub jec ts w erein energy ba lan ce). N u trien t u tiliza tion w as c lose r to nu tr ien tin take fo r the h igh -fa t d ie t than fo r the low -fa t d ie t. com parin gthe ca lcu la ted FQ w ith the presen ted RQ valu e (T ab le 2 ).

A bbo tt e t a l (2 9) m easured energy m etabo lism in sub jec tsa fte r 5 -43 d on h igh -fa t and low -fa t d ie ts in a m etabo lic w ard .Part o f the sub jects a te the h igh -fa t d ie t on th e firs t adm issio nan d the o thers s tar ted w ith the low -fa t d ie t. T he in te rva l b etw eenfirs t and second adm ission w as m ore than 4 w k. S ub jec ts w erein energy ba lance : the m ean d if fe rence be tw een en ergy in tak ean d en ergy ex pend itu re (< 5% ) w as w ith in the erro r range ofb o th m easurem en ts . FQ and RQ w ere no t d iffe ren t on the h ig h-fa t d ie t, ind ica tin g tha t nu trien t in tak e and nu trien t u tiliza tionw ere th e sam e. O n the h igh -carbohyd ra te d ie t, R Q w as system -a tica lly low er than FQ(P < 0 .00 1 , ind ica ting tha t fa t ox ida tion

w as h igher than fa t in take , assum ing there w as n o ne t p ro teinsyn thesis o r ox id ation .

H ill e t al (3 0) m easured nu trien t u tiliza tio n in su b jec ts a fte r3 and 7 d on th ree d ifferen t d ie ts: a m ix ed d ie t, a low -fa t d ie t,and a h igh -fa t d ie t. U nfortun a te ly . th ey d id no t rep ort w h etherthe sub jec ts w ere in energy ba lance : they presen ted on ly da taon d ie t com po sition an d nu trien t u tiliza tion . F or a ll d ie ts the rew as a ten dency fo r RQ to be low er than FQ . H ill e t a ls exp la -na tio n fo r the d isc repancy is the d ifficu lty in using in d irect ca l-o rim etry com bined w ith food-tab le nu trien t ana lys is (27 ).

N utrien t add itio n and nu tr ien t ba lanceD allosso and lam es (3 1 ) inc reased energy in take fo r 1 w k by

50% w ith fa t, m ain ly as do ub le c ream . a fte r a l-w k observa tionon a m ain tenance d ie t w ith a c :p :f o f 57 : 1 3 :30 en% . S ub jec tsw ere o bserv ed on days w hen th ey h ad a low ac tiv ity leve l an don d ay s w hen they h ad a h ig h ac tiv ity lev e l. T he carbo hydra teand pro te in ba lances w ere no t af fected b y the ad d ition of fa t tthe d iet. T he 5 -M I fa t su pp lem en t w as m ain ly sto red as faju dg ing from th e chang e in fa t ba lan ce from + 14 25 to +163 27 g/d and from -14 19 to +151 33 g /d on day s w ithlow ac tiv ity and h ig h activ ity . respec tive ly . T h e m ean ne t fasto rag e in term s of energ y ca lcu la ted from th ese figu res is 5 .5M i on low -ac tive d ays and 5 . 1 M l o n h igh-ac tive days. S ch u tze t a l (32) d id a com parab le exp er im en t in w h ich they m easuredenergy ex pend itu re an d su bstra te u tiliza tion over 2 -d in te rva lsin sub jec ts g etting a m ain tenance d ie t on the first d ay (c :p :f 501 5 :3 5 en% ) and the d iet w ith the sam e am ounts o f ca rb ohydrateand pro te in bu t tw ice the am ount o f fa t on the second day . Othe first day , the m ean d ifferen ce be tw een in take and expend itu rew as 0 .1 0 .2 M I. in d icating sub jec ts w ere in en ergy b a lance .T he 24 -h FQ and m ean RQ values w ere 0 .87 and 0 .85 0 .01 ,respec tive ly . ind ica ting tha t sub jec ts w ere in nu trien t ba lance aw ell. O n the second day the energ y expen d itu re an d sub stra teu tiliza tio n w ere no t changed by the fa t supp lem en t. T he energ yba lan ce becam e +4 . 1 0 .3 M i, com pared w ith the ex tra in takeof4 . I 0 . 1 M l, tha t is , the fa t su pp lem en t w as sto red as observedbefo re (3 1. A ch eson e t al (33) overfed sub jec ts fo r I w k w ithcarbohydra te a fte r a 3 -d in te rva l w ith a res tricted d ie t to dep le tethe g ly co gen s to res. T he energy-res tricted d ie t w as 6 .7 M l/d .w ith c :p :fo f 1 0 :15 :75 en% . w hereas energy exp end itu re on theth ird day w as 9 .6 M l. Su bsequ en tly . sub jec ts go t a d ie t w ithc :p :fo f86 : 1 1 :3 en% , in creas ing energy in take ov er 7 d from I 5.5to 2 1 .0 M I/d . O n the first day o foverfeed ing . the energ y surp lu sw as fu lly s to red as g lycogen : then , de n ovo lip ogenes is s tar tedm aking up a ll o f the energy surp lus f rom th e fifth day of o ver-feed ing o nw ard s. A t the en d of the overfeed ing period . the rew as a g lycog en ga in of 0 .7 kg and a fa t ga in of 11 kg , to ge th errep resen t ing 75 % of the energy con sum ed in excess o f m ain te-n an ce requ irem en ts.

D iscu ssion and con c lu sionBased on the lite ra tu re re fe rred to . th ere is ev idence tha t

ch ange to a fa ttie r d iet leads to an in crease in bo dy w eig h t. C om -b in ing th is w ith th e fac t tha t obese peop le tend to ea t m ore fleads to the con clus ion tha t b ecom in g overw eigh t can b e pre-v en ted by reduc ing the fat con ten t o f the d ie t. S econ d ly . the re


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FQ, RQ. AN D ENERGY BALA NCE 7 6 3 Sis ev idence that the body has a lim ited ability to o x idize fatcompared w ith the ability to ox idize carbohydrate and prote in.It is o ften suggested that this lim itation is more pronounced inobes ity -susceptible indiv iduals (34). Thus some indiv iduals aremore like ly to become obese consuming a high-fat die t than areothers. On the other hand. intervention studies do not supportunequivocally the body s lim itatio ns to burn fat.

S hort-term studies , measuring substrate utilizatio n over up to14 h after a meal, show how the carbohydrate o x idatio n is in-creased after a high-carbohydrate meal w hereas addition o f fatto a meal does not influence fat ox idation (Table 2) . In the longterm . measuring substrate utilization ov er 24 h, there are in-dications of the oppo site. A t die ts higher in carbohydrate thereis a bigger discrepancy betw een FQ and RQ such that RQ islow er than FQ (Table 3) . This should mean that substrate uti-lization is c lo ser to substrate intake for die ts higher in fat thanfor die ts higher in carbohydrate . a phenomenon that cannot bereadily explained.

U nder conditio ns o fperfec t energy and nutrient balance . FQmust equal RQ. U nder conditions ofenergy or nutrient imbal-ance, a normal-w eight adult stores or mobilizes, in the long term .near1 all energ y in the form o f body fat. Then. the body doesnot use pro te in and carbohydrate reserves for energy sto rage orenergy mobilization. The carbohydrate s to re in the form of liv erand musc le g lycogen fluctuates betw een 250 and 500 g , o r 4 and8 M l. Reference man has a musc le mass of 30 kg w ith 7 .5 kgprote in, or an energ y equivalent o f 1 20 Mi. but changes in mus-c le mass are ins ignificant in terms of energ y compared w ithchanges in fat mass, unless body fat is nearly deple ted. Thus , inthe long term , an RQ higher than the FQ implicates convers ionof carbohydrate or prote in to body fat. and an RQ low er thanthe FQ, a mobilizatio n ofenergy from body fat.

Combining the observ ation of the low er-than-expected RQfor a high-carbohydrate die t w ith the fact that an RQ measuredover a long-term interval can only be low er than the FQ bymobiliz ing body fat leads to the conclus ion that high-carbohy-drate die ts induce body fat loss. A part from studies re ferred earlier(5 . 6 ) , a recent s tudy sugg ests that the macronutrient compositionof the die t plays a ro le in the energy requirem ent for w eightmaintenance . Prew itt e t al (35) repo rted data on 1 8 w omen con-suming a standard die t for 4 w k (c:p:f44:19:37 en%), fo llow edby 20 w k of low -fat die t (c :p:f 60: 19:2 1 en%). Energy intake ofthe subjects w as adjusted to maintain body w eight throughoutthe study period. that is. intake w as increased or decreased w henbody w eight decreased o r increased by 1 kg , respective ly .Comparing the initial 4 -w k interval for the standard die t w iththe last 4 w k for the low -fat die t, the mean energy intake increasedw ith 1 9% and the mean body w eight decreased w ith 2 kg . Thus.a high-carbohydrate die t resulted in a s ignificant reduction inbody w eight despite a substantial increase in energ y intake aimedat w eight maintenance .

This rev iew leads to the suggestion that energy expenditure ishigher for low -fat, high-carbohydrate die ts than for high-fat, low -carbohydrate die ts. Conv incing ev idence for this at this po int isnot yet available . Current studies inc lude measurement of energyexpenditure over short time intervals, up to 24 h in a respirationchamber, and calculation of energy expenditure from energyintake and changes in body compo sitio n. Future studies shouldinc lude direct measurement of energy expenditure for1 w kunder no rmal liv ing conditions . # { 1 6 3 } 3

ReferencesI . Fabry P. Feeding pattern and nutritio nal adaptations. Prague: A ca-

dem ia. and London: B utterw orths . 196 9 .2 . N ational Research Council (U S). C ommittee on D iet and Health.

D ie t and health: implications fo r reduc ing chronic disease risk.W ashing ton. D C: N ational A cademy Press. 1989 .

3. A tw ater WO. B ryant A P. The availability and food values o f foodmaterials. In: The I 2th annual report o fthe S torrs . CT. A griculturalExperimental S tation. S to rrs, CT: Storrs . CT. A gricultural Experi-ment Statio n, 19 00:73-I 10 .

4 . B ray GA . B ethune JE. eds . Treatment and management of obes ity .Hagerstow n. MD : Harper & Row , 1 974 .

5 . D uncan KH. Bacon IA . W einsier RL. The effec ts o f high and lowenergy density die ts on satiety . energy intake . and eating time ofobese and nonobese subjects . Am I Clin N utr 19 83:37:76 3-7 .

6 . Lissner L, Lev itsky DA . S trupp BJ. Kalkw arf HI. Roe D A . D ietaryfat and the regulation o f energy intake in human subjects . A m JClin N utr 1 987:46 :8 86-92 .

7 . A dolph EF. U rg es to eat and drink in rats . A m I Phy sio l 19 47:151 :1 1 0 - 2 5 .

8. Porikos KP. B ooth G. V an Itallie TB . Effect o fcov ert nutritiv e di-lution on the spontaneous fo od intake o f obese indiv iduals: a pilo ts t u d y . Am I Cl i n Nu t r 1 9 7 7 : 3 0 : 1 6 3 8 - 4 4 .

9 . Porikos KP. Contro l o ffood intake in man: response to cov ert caloricdilution of a conventional and palatable die t. In: C ioff i LA , JamesWPT, V an Itallie TB , eds . The body w eight regulatory system: normaland dis turbed mechanisms. N ew Y ork: Raven Press, 198 1:83-7 .

10 . Fo ltin RW . Fischman MW , Emurian CS , R achlinski. Compensatio nfor caloric dilutio n in humans g iven unrestric ted access to food ina res idential laboratory . A ppetite I 9 88:10 :1 3-24 .

I 1 . Jiang C-L. Hunt IN . The re lation betw een free ly chosen meals andbody habitus. Am I Clin N utr 1983:38 :3 2-40 .

12 . D reon DM , Frey-Hew itt B , Ellsw orth N , W illiams PT, Terry RB ,Wood PD . D ietary fat:carbohydrate ratio and obesity in m iddle-ag ed men. A m I Clin N utr 19 88:47:995 -1000 .

I 3. Trembla A . Plourde G . D espres I-P. B ouchard C . Impact o f die taryfat content and fat ox idation on energy intake in humans . A m IC lin N utr 198 9:49:799 -805 .

14 . Miller WC. Lindeman AK. Wallace I. N iederpruem M . D iet com-po sitio n, energy intake . and exerc ise in re latio n to body fat in menand w omen. A m I Clin N utr 19 90:52:42 6-30 .

I 5. S choe ller D A . How accurate is self-reported die tary energy intake?Nu t r Re v 1 9 9 0 : 1 0 : 3 73 - 9 .

16 . Westerterp KR . V erboeket-van de V enne WPHG. M eijer GA L. Hoo rF ten. S e lf-reported intake as a measure for energ y intake. a validatio nagainst doubly labe lled w ater. In: A ilhaud G. Guy-Grand B . LafontanM . R iequier D . eds. Obes ity in Europe 91London: John Libbey .1992:17-22 .

I 7. Romieu I. W ille tt WC. S tampfer M I, e t al. Energy intake and otherdeterm inants o f re lative w eight. A m I Clin N utr I 988 :4 7:406-12 .

18 . Miller WC. D iet compos ition. energy intake , and nutritional s tatusin re lation to obes ity in men and w omen. Med S ci Sports ExercI 9 9 1 : 2 3 : 2 8 0 - 4 .19 . Flatt IP. The difference in the storag e capac itie s for carbohydrateand fo r fat. and its implications in the regulatio n of body w eight.A nn N Y A cad S ci 1987 :4 99:104-23 .

20 . Frayn KN . Calculation of substrate ox idation rates in v ivo fromgaseous exchange . I A ppI Phys io l 198 3:55:628 -34 .

2 1 . Garlick P1 , M cN urlan MA . McHardy KC . Factors contro lling thedispos itio n of primary nutrients. Proc N utr S oc 1988:47:169 -76 .

22 . A cheson KJ. Flatt IP, l#{ 23 3} quier. G lycogen synthesis versus lipogenesisafter a 500 gram carbohydrate meal in man. Metabo lism 1982:31:I 2 3 4 - 4 0.


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7 6 4 5 WESTERTERP23 . A cheson K I. S chu tz Y . B essa rd T . R avu ss in E . l#{23 3}qu ier. F la tt IP .

N u tritiona l in fluences o n lipo genesis and therm ogenesis a fter a ca r-bohydra te m ea l. Am I Physio l 198 4 :246 :E 62 -70 .

24 . F la tt JP . R avussin E . A cheson 10 . l#{2 33}qu ie r. E ffec ts o f d ie ta ry fa ton p ostp rand ia l subs tra te o x ida tion and on carb ohydrate an d fa tba lan ce . I C lin Inves t 1 985 :76 :1 019-2 4 .

25 . V erboek et-v an de V enne PH G . W ester te rp K R . In flu ence of thefeed ing frequ en cy on nu trien t u tiliza tion in m an: co nsequ en ces fo renergy m etabo lism . E url C lin N utr 199 1 :45 :161 -9 .

26 . H un ri M . B urnand B , P itte t P h . lequ ie r E . M etabo lic e ffec tso fa m ixed and a h igh -carbohyd ra te low -fa t d ie t in m an . m ea-su red ov er 2 4 h in a resp iration cham ber . B r I N utr 19 82 :47 :3 3 - 4 3 .

27 . L ivesey G . E lia M . E stim atio n of energy ex pend itu re , ne t ca rb o-h ydra te u tiliza tio n . and ne t fa t ox ida tion and sy n thesis by in d irectcalo r im etry : eva lua tion of e rro rs w ith sp ecia l re fe rence to the de ta iledcom pos itio n offue ls. A m J C lin N utr 1988 :4 7 :608-28 .

28 . Lean M E l, Jam es W PT . M etabo lic e ffec ts o f isoenerg etic nu trien texchange over 24 hours in re la tion to obes ity in w om en . In t I O bes1 9 88 : 1 2 : 1 5- 2 7 .

29 . A bbott W G H , H ow ard BV , R uoto lo G . R avussin E . E nerg y expen-

d itu re in hum ans : e ffec ts o f d ie ta ry fa t and carboh ydra te . Am IPh y s i o l 1 9 90 : 25 8 : E3 4 7- 5 I .

30 . H ill 1 0 . P ete rs IC . R eed GW . S ch lund t D G . Sh arp T . G reene H L .N utrien t ba lance in hum ans : e ffec ts o fd ie t com pos ition . A m I C linNu t r 1 99 1 : 5 4 : 1 0 - 7 .

31 . D allosso HM . Jam es W PT . W hole -bo dy ca lo rim etry s tud ies in adu ltm en : 1 T he effec t o f fat over-feed in g on 24 h energy expend itu re .B r I N utr 1984 :5 2 :49-64 .

32 . S chu tz Y . F la tt IP . J#{2 33}qu ie r. Fa ilu re o fd ie ta ry fa t in tak e to prom otefa t ox id ation : a fac to r favoring the deve lopm ent o f ob es ity . A m IC lin N utr 19 89 :50 :307 -14 .

33 . A cheson K I. S chu tz Y . B essa rd T , A nan tharam an K . F la tt IP , an dJ#{233}qu ie r. G ly co gen s to rage capac ity an d de n ovo lipogenes is d uringm assive carb ohydrate o verfeed ing in m an . A m I C lin N utr I 988 :48 :240-7 .

34 . Zurlo F . L illio ja S . E spo sito -D el P uen te A . et a l. L ow ra tio o f fa t toca rbo hydra te ox id a tion as p red icto r o f w eig h t ga in : s tudy of 24-hRQ . A m I Phys io l l9 90 :259 :E 650-7 .

35 . P rew itt TE . S chm eisse r D . B ow en PE . e t a l. C hanges in body w eigh t.b o th com po sition . an d energy in take in w om en fed h ig h- and low -fa t d ie ts. Am J C lin N utr 1 99 1 :54 :3 04-10 .

DiscussionM ichae l A C raw ford : T h is m ay b e a na ive qu estio n . bu t I w asin te res ted in th e ana logy tha t you g av e us-your m ode ls o f thetest tube an d the b arre l. the test tu be of ca rboh ydra te and thebarre l o f fat. W hat seem s to be sligh tly ou t o f focus to m e w asthe s ize of the inpu t you show ed . Y ou show ed tw o little po ts.O ne ofca rb ohydrate and one offa t o fd if fe ren t p roportion s andd iffe ren t d iets . It seem s to m e th at if y ou had represen ted thoseinpu ts in p roportion to the da ily am ount o fs tu fftha t w as go ingin , one w ould have seen th a t th e am ount o f ca rb ohyd ra te th atw en t in over a 2 4-hou r period w ould be rea lly very m uch la rg erthan the am ount o f ca rb ohyd ra te th at w as s to red in th e tes ttube . A 24-hour inpu t o f ca rboh ydra te is qu ite a lo t in a h igh-ca rbohydra te d iet. A t th e sam e tim e . the barre l is fu ll o f fa t, sotha t carbohyd ra te . a lthou gh com ing th rou gh the carboh ydra terou te , is ac tua lly filling up the fa t ba rre l because it doesn t s to retha t am oun t o f ca rboh ydra te . So . it h as to be conv erted to fatand fill u p the fat ba rre l. T he energy p rocess o fcon vertin g th atca rbohydra te to fa t needs to be a sort o f n eg a tive cons id erationin te rm s o fth e ov erall en ergy ba lance of th e ind iv idu al. I w ond erto w ha t ex ten t tha t con tribu tes to d istu rb ing these rela tionsh ipsand exp la in ing w hy fa t is go in g s tra ig h t in to the barre l an d doesntreally have any effec t o f energy . T he carbohydra te g o ing in de-m ands energy to co nvert it in to fat and desto r ts it a s su ch . D oestha t co nfound the equa tion w ith regard to a r ich -ca rb ohydratevs a rich -fa t d ie t?

K laas R W este rte rp : I th in k you are s tressing an in teres ting po in t.I don t know w hether th is m ode l w as rea lly on th e righ t scaleand , as you say . w e ea t a lo t o f ca rbo hydra te in propo rtio n toour ca rboh ydra te s to res. O n the o ther hand , the re is n o t m uchin fo rm ation on w hether w e rea lly h av e to convert ca rbohydra teto fa t, apart from the o ne s tu dy I show ed you , and m ayb e oneor tw o o thers in the lite ra tu re in w hich you can see tha t a t leastthe re is a day-n ig h t rhy thm in su bstra te u tiliza tion . T h at rhy thmsuggests th a t w e m igh t sto re p art o fthe carbohyd ra te w e consum edurin g th e d ay fo r overn ig h t use . Th a t has been seen in sm all-

an im al stud ies . bu t you cant rea lly com pare those w ith hum ans tud ies because w e as hum ans h av e a b ig in tes tine fo r food s to rageand w e have g o t a re la tiv ely fa r low er energy m etabo lism peun it bo dy w eigh t. M ayb e the reason fo r hav ing a h igher en ergyexp en d itu re a t a h igh -carbohydra te d iet is the conv ersion of ca r-b ohydrate to fa t.E ric R avuss in : Iw ould lik e to ex pand a little o n th is comm ent.I th ink th at in m en there is less and less ev id ence tha t de no volipogenes is p lays an im portan t ro le . an d in the stud y th at yo ushow ed from K ev in A cheson , in w hich he gave an enorm ousam ount o fca rbohvdra te (500 g). W e tried tha t firs t a s on e m ea l.b u t a fte r the su b ject had prob lem s , w e offe red it at 250 gram sand a t tw o tim es 125 gram s. It w as very , ve ry d iff icu lt to ind ucea s ig n ifican t am oun t o fde novo lipog enesis. I ag ree tha t ind irec tca lo rim etry doesnt d iffe ren tiate be tw een ox ida tion and go ingin to fa t. bu t I th ink tha t the p o in t is tha t th ere is little room fod e novo lipo genesis in m en . T here fo re . you are righ t w hen yousay tha t m aybe 50- 10 0% of th e g lycog en s to res a re rep laced ona da ily basis vs< 1% for fa t. I th ink tha t m o st o fthe carb ohyd ra teinges ted is e ithe r sto red as g lycogen o r ox id ized in to CO 2.th ink tha t the en zym atic ac tiv itie s o fthe lip ogen ic enzym es arevery low in m en , and recen t stud ies u sing stab le iso tope show edtha t de n ovo lipog en es is is ve ry ins ig n ifican t in m an .W este rte rp : I ag ree w ith tha t, bu t on the o th er hand . th e stud ieso fA cheso n w ere sh ort-te rm stud ies . In the long te rm . w hen youcon sum e a h ig h-ca rboh ydra te d ie t. y ou cant really sto re th isam oun t o f carbohyd ra te in y our g lycog en s to res b ecause th eyare ju st no t b ig enough . So . y ou have to do som eth ing w ithw hen you are in a p ositive energy b alance . b u t app aren tly youtend to be in a neg ative energy b alance on a h igh -ca rbohydra ted ie t. W e do no t ye t have any reason fo r tha t. M aybe you havea sug gestion fo r w hy you tend to be in a n eg a tive energy b alanceon a h igh carboh ydra te d ie t. W hy w ould you r energy exp en d itu reg o up?R avuss in : In all the stud ie s o fov e rfeed in g . fo r exam p le. S chu tz sstu dy . you need to push a lo t o fca rb ohyd ra te th rough the system .


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FQ. RQ. AN D EN ERGY BA LAN CEWhen w e talk about w eight gain in obese people . they are ob-v iously in positive energy balance . but by a minute amount ona daily basis . There is lim ited sto rag e capac ity in men, and there-fore carbohydrate is ox idized: maybe there is a little lipo genesis .There w as the B ritish schoo l in the l96 0s that said that lipog enesism ight be higher in lean people because it is an energy -costlypro cess. I dont know w hat is the status of that now .

N lartijn Katan: Could I sum a little note of caution about theef fectiveness o f high-carbohydrate die ts in reduc ing obesity be-cause the f inal tests are lo ng-term contro l trials and there havebeen a few ofthose? In 1970 the N atio nal D ie t Heart S tudy w aspublished in ( i rcu la t ion , w here large groups of m iddleag edAmerican men w ere g iven die ts o f 40% or 20% energy as fat.There w as some w eight loss in the 20-en%-fat group but thatw as very minor, 1 o r at most 2 kg in the firs t few months and

7 6 5 Sthan no chang e for the rest o f the year. There is a recent pub-lication from the pilo t study for the breast-cancer-die tary-fattrial, w here you see a s im ilar phenomenon. that indeed thw omen on the very-low -fat die t los t some w eight but nothinglike the amounts y ou w ould expect from the sho rt-term trials ,again something like 1 or 2 kg over the year. There are also thedata from the S eattle die tary alternativ e trial. a 2 -year study thatI think is s till in press, w here again y ou see in m iddleaged manonly I kg w eight loss on 20 vs 40 en% of fat. I think theremore go ing on than just the mechanisms that w e have beentalking about. The body seems to resis t w e ight loss even on themore carbohydrate -rich die ts.W esterterp: M aybe you are right. T he only problem is the controloffo od intake in these types ofs tudies. On the other hand. long-term experimental feeding studies are costly . Therefore , w e haveto accept the results as they are .

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Am J Clin Nutr 1993 Westerterp 759S 64S