International Journal of Obesity (2001) 25, 1129±1135
ß 2001 Nature Publishing Group All rights reserved 0307±0565/01 $15.00www.nature.com/ijo
PAPERConjugated linoleic acid (CLA) reduced abdominal
adipose tissue in obese middle-aged men with signs
of the metabolic syndrome: a randomised controlled
trialU RiseÂrus1*, L Berglund1 and B Vessby1
1Clinical Nutrition Research Unit, Department of Public Health and Caring SciencesaGeriatrics, Faculty of Medicine, Uppsala
BACKGROUND: Abdominal obesity is strongly related to metabolic disorders. Recent research suggests that dietary conjugated
linoleic acid (CLA) reduces body fat and may improve metabolic variables in animals. The metabolic effects of CLA in
abdominally obese humans have not yet been tested.
OBJECTIVE: To investigate the short-term effect of CLA on abdominal fat and cardiovascular risk factors in middle-aged men
METHODS: Twenty-®ve abdominally obese men (waist-to-hip ratio (WHR), 1.05Æ 0.05; body mass index (BMI), 32Æ 2.7 kgam2
(meanÆ s.d.)) who were between 39 and 64-y-old participated in a double-blind randomised controlled trial for 4 weeks.
Fourteen men received 4.2 g CLAaday and 10 men recieved a placebo. The main endpoints were differences between the two
groups in sagittal abdominal diameter (SAD), serum cholesterol, low-density lipoprotein, high-density lipoprotein, triglycerides,
free fatty acids, glucose and insulin.
RESULTS: At baseline, there were no signi®cant differences between groups in anthropometric or metabolic variables. After 4
weeks there was a signi®cant decrease in SAD (cm) in the CLA group compared to placebo (P 0.04, 95% CI; 71.12, 70.02).
Other measurements of anthropometry or metabolism showed no signi®cant differences between the groups.
CONCLUSIONS: These results indicate that CLA supplementation for 4 weeks in obese men with the metabolic syndrome may
decrease abdominal fat, without concomitant effects on overall obesity or other cardiovascular risk factors. Because of the
limited sample size, the effects of CLA in abdominal obesity need to be further investigated in larger trials with longer duration.
International Journal of Obesity (2001) 25, 1129 ± 1135
Keywords: conjugated linoleic acid (CLA); abdominal obesity; abdominal sagittal diameter; metabolic syndrome; cardiovascular
risk factors; randomised controlled trial (RCT)
CLA comprises a group of positional and geometric isomers
Conjugated linoleic acid (CLA) is an unsaturated fatty acid
of conjugated octadecadienoic acid, derivates of linoleic acid
that has been shown to reduce body fat and increase lean
(C18:2n-6) produced by bacterial biohydrogenation in the
body mass in animals,1±5 by as yet unknown mechanisms.
ruminant gut.6 In humans, CLA is mainly derived from dairyand ruminant meat sources,7 and has been found in serum8and in human adipose tissue.9 Recent data have shownbene®cial effects of CLA on several components of themetabolic syndrome, in Zucker diabetic fatty rats (ZDF),
*Correspondence: U RiseÂrus, Clinical Nutrition Research Unit, Department
such as normalized glucose tolerance and reduced hyper-
of Public Health and Caring SciencesaGeriatrics, Faculty of Medicine,
insulinaemia, and plasma levels of free fatty acids (FFA).10
Uppsala University, Box 609, 751 25 Uppsala, Sweden.
Furthermore, in CLA-fed rabbits and hamsters, the blood
lipid pro®le was signi®cantly improved11 and signs of early
Received 4 February 2000; revised 31 July 2000;
atherosclerosis were decreased as compared to controls.12,13
Conjugated linoleic acid and abdominal obesity
Abdominal visceral obesity, has been suggested to be a key
factor in the metabolic syndrome14 and the most prevalent
The inclusion criteria were chosen to select obese men with
cause of the atherogenic dyslipidaemic states associated with
signs of the metabolic syndrome (abdominal obesity, dys-
cardiovascular disease in Western populations.15 Thus, men
lipidemia, hypertension and impaired fasting glucose). The
with visceral obesity are an appropriate risk group to test the
inclusion criteria were, as assessed by screening: age between
putative bene®cial metabolic effects of CLA treatment.
30 and 65 y, abdominal obesity (waist circumference b94 cm
Furthermore, epidemiological data from a population of
and waist-to-hip ratio (WHR) b0.95), BMI b27 and
elderly men showed an inverse correlation between esti-
` 39 kgam2, and with stable body weight the preceeding 3
mated dietary intake of milk fat and abdominal obesity,16
thus suggesting some indirect evidence for the postulatedmetabolic effects of CLA when consumed in high amounts. The sagittal abdominal diameter (SAD) has been suggested tobe the best simple anthropometric measurement of visceral
fat,17±19 and is strongly associated with cardiovascularrisk20±24 and mortality among men.25
Subjects with a history of signi®cant disease or with abnor-mal laboratory test results of clinical signi®cance were
The antiobesity properties and metabolic effects of CLA
excluded as well as those on medications or dietary supple-
are at present only described in animals, and should there-fore be clinically tested in obese humans. The aim of the
ments known to affect glucose and lipid metabolism, bodycomposition or eicosanoid production (eg salicylates and
present trial was to investigate the short-term effects of CLAcompared to placebo on abdominal adipose tissue and car-
®sh-oils). Treatment with antihypertensive drugs wereaccepted if the subjects continued to take the same drug
diovascular risk factors in men with signs of the metabolicsyndrome. To the best of our knowledge, the present study is
the ®rst randomised controlled trial in humans, investigat-
The primary outcome in the present trial was to investi-
gate any statistical differences between CLA and placebo in
ing the effects of CLA treatment in a cardiovascular high-riskgroup of abdominally obese middle-aged men.
SAD (representing visceral and total abdominal adiposetissue), serum cholesterol, fasting triglycerides (TG), low-density lipoprotein (LDL), high-density lipoprotein (HDL),
FFA, plasma glucose and serum insulin. Secondary outcomes
of interest were anthropometry and blood pressure.
Twenty-®ve abdominally obese men (all Caucasian),between the ages of 39 and 64 y, were recruited through anadvertisment in the local newspaper of Uppsala, Sweden. Sixty men were invited to a screening test, which included
anthropometry, serum lipids, plasma glucose, blood pres-
The current trial was performed between April and May
sure, kidney, liver, thyroid function and a medical question-
1999. All men were randomly assigned to treatment (CLA)
naire. The men who ful®lled the inclusion criteria (described
or placebo. Each group received seven CLA or placebo
below) were informed about the study protocol and invited
capsules per day (divided in two doses). Compliance was
to participate. Twenty-®ve men ful®lled the inclusion cri-
monitored by counting any returned capsules and by follow-
teria, agreed to be randomly assigned to study groups, and
up interview. The blinding was obtained using capsules
identical in taste, colour, size and odour, packed in identical
At the clinical baseline examination one patient was
bottles, with one bottle per subject. The daily dose of CLA
found to be hypertensive and was, after a re-examination,
comprised 4.2 g and the same amount of olive oil was used as
treated with a b-receptor blocker (metoprolol). This patient
placebo. The predominant isomers used in CLA preparations
wished to complete the trial and was included (data on blood
are cis9, trans11 CLA 18:2 and trans10, cis12 CLA.1 The
pressure from this patient was excluded from statistical
isomer content of the current CLA preparation was as fol-
lows: 37.0% t10c12 CLA, 36.9% c9t11 CLA, 1.4% t, t9,
One subject declined on the ®rst day of the study and was
11 10, 12 CLA, 1.3% c9c11 CLA, 0.9% c10c12 CLA, 13.9%
excluded before taking any capsules. The reason for declin-
18:1c9, 4.3% 16:0, 1.4% 18:0. Both active (CLA 80) and
ing was gastrointestinal disorders prior to the baseline exam-
placebo capsules were prepared by Natural Lipids Ltd, Hove-
ination. This subject did not differ in characteristics in terms
bygda, Norway, which also was responsible for the individual
of age or biochemical or anthropometric data as compared to
randomisation and blinding of capsules. During the trial, the
the men who completed the trial. The results and conclu-
code was kept in sealed envelopes that were kept in a closed
sions presented and discussed in this paper are based on the
box located at the department of Geriatrics. None of the
24 subjects with complete data at 4 weeks. The protocol to
investigators, nurses, analysts or patients knew the identity
this study was approved by the Ethics Commitee of the
of the treatments until the codes were revealed at the end of
Faculty of Medicine of Uppsala University.
Conjugated linoleic acid and abdominal obesity
magnesium chloride solution.30 LDL-cholesterol was calcu-
The clinical examination was conducted in the morning
lated according to the formula of Friedwald. Sample for the
between 07:15 and 09:00, after written and oral instructions
determination of insulin and FFA were stored at 770C. FFA
to fast for 12 h, restrain from smoking, snuff or physical
was measured by an enzymatic colorimetric method (Wako
activity in the morning, and to avoid alcohol the day before
Chemical GmbH, Germany). Insulin were measured in
the clinical examination. All men were encouraged to main-
serum by an enzyme immunoassay, ELISA-kit (Mercodia
tain their usual diet and exercise habits throughout the
AB, Uppsala, Sweden) in a Bio-Rad Coda automated EIA
course of the study. After oral information, the same inves-
analyser (Bio-Rad Laboratories AB, California, USA). Insulin
tigator measured anthropometry and blood pressure, fol-
and FFA were analysed at one run. Plasma glucose was
lowed by blood samples taken by a nurse. Blood pressure
measured with an enzymatic method, using a Hitachi ana-
was measured on the right arm with the subject in the supine
lysis system 717 (Boehringer Mannheim, Germany).
position after at least 5 min rest, by indirect auscultation andby a mercury sphygmomanometer. Systolic and diastolicblood pressure were de®ned as Korotkoff phases 1 and 5,
respectively. Clinical examination at 4 weeks also included a
Values are expressed as meansÆ s.d. All data were continous
systematic food frequency interview, for estimation of diet-
and on an interval scale. Variables with skewed distributions
ary CLA intake and to obtain the dietary history for the
(TG and insulin) were log transformed before analyses. A
preceding month.26 All men were asked about their habitual
nonparametric test was used if data were not normally
food consumption during the preceeding 4 weeks, with focus
distributed after logarithmic transformation. The paired t-
on sources of CLA. During the interview, various household
test was used to analyse the differences within the groups
measures were used to identify proper portion sizes. Dietary
from baseline to 4 weeks. The mean differences between
intake of CLA was calculated by use of food-composition
groups at baseline and after 4 weeks were assessed with an
data of the Swedish National Food Administration;27 when
unpaired t-test, with 95% con®dence intervals (CI) calcu-
necessary, the portion sizes of different food items were
lated according to standard procedures. For variables (waist)
converted to weight on the basis of standard portions.
that were not normally distributed after logarithmic trans-
Calculations of the CLA content in various dairy and meat
formation, the Mann ± Whitney nonparametric test was used
products are based on the mean CLA content in dairy
for analyses. All tests were two-tailed and a P-value ` 0.05
products (2.5 ± 17.7 mgag fat),28 butter (6.2 mgag fat) and
was regarded as signi®cant. Statistical calculations were per-
formed using the JMP software package (SAS Institute Inc.,
All anthropometrics were measured by one trained inves-
tigator. Body weight was measured using an electronic scaleto the nearest 0.1 kg, with the subjects wearing light clothingand no shoes. Height was measured without shoes to the
nearest 0.5 cm. Bod mass index (BMI) was calculated as the
weight (kg) divided by the square of the height (m). SAD
Twenty-four men completed the study after being randomly
(antero-posterior) was measured with patients in underwear
assigned to CLA treatment (n 14), or placebo (n 10).
and in a recumbent position with hips ¯exed, on a ®rm
During the 4 weeks only one subject withdrew.
examination table. At the level of the iliac crest ( L4-5), the
At baseline, there were no signi®cant differences between
perpendicular distance between the examination table up to
the two groups after randomisation, in age (Table 1), anthro-
the horizontal level was measured during a normal expira-
pometry or in any other characteristic (Table 2). Fourty-four
tion to the nearest 0.1 cm.17 Waist circumference was mea-
percent of patients were hypertensive, de®ned as a mean
sured in standing position after a normal expiration, with a
systolic pressure !140 mmHg or mean diastolic pressure
nonstretchable tape measure, at the level midway between
!90 mmHg or if the subject was receiving antihypertensive
the caudal part of the lateral costal arch and the iliac crest.29
drugs. No patient in the study sample had a diagnosis of type
Hip circumference was measured at symphysis trochanter
2 diabetes or history of cardiovascular events.
Table 1 Demographic and anthropometric characteristics at baseline
Laboratory proceduresBlood was drawn from an antecubital vein, into vacuum
tubes and centrifuged (20 min) at 2000 g after 2 h of coagula-
tion at room temperature. Total cholesterol and TG levels in
serum were assayed by enzymatic techniques, using a Mon-
arch 2000 centrifugal analyser (Instrumentation Labora-
tories, Lexington, MA). HDL was isolated by centrifugation
aThere were no signi®cant differences between groups using unpaired t-tests.
and precipitation with a sodium phosphotungstate and
Values are the meanÆ s.d. BMI, body mass index, WHR, waist-to-hip ratio.
Conjugated linoleic acid and abdominal obesity
Table 2 Clinical characteristics of men at baseline and after 4 weeks of treatment with CLA (n 14) or placebo (n 10)
BMI, body mass index; SAD, sagittal abdominal diameter; WHR, waist ± hip ratio; Chol, serum cholesterol; LDL, low density lipoprotein; HDL, high density
lipoprotein; TG, triglycerides. Values are the meanÆ s.d. and 95% con®dence interval (CI).
Signi®cant differences between the two groups using unpaired t-test: *P ` 0.05. Signi®cant differences within groups using paired t-test: {P ` 0.01, {P ` 0.001.
The supplements were well-tolerated in all patients, with
no adverse events clinically detected or reported. Compli-
The estimated mean CLA intake from dietary sources was, for
ance did not differ between groups, with 96% of the capsules
the whole group, 328 mg CLAaday. The mean intake of CLA
from dietary sources was 311 mg (range 123 ± 470 mg) in theCLA group, and 346 mg (range 156 ± 590 mg) in the placebogroup, showing no statistical signi®cance between groups(P 0.24). These data suggest that the CLA supplementation
corresponded to an average daily dose, which was approxi-
The 4 week treatment with CLA induced a signi®cant reduc-
mately 13-fold higher than what was usually obtained from
tion of SAD, as compared to placebo (P 0.041, 95% CI;
71.12, 70.02; Table 2), with a signi®cant decrease of SADwithin the CLA group (P 0.003), while there was no mea-surable change in the placebo group (P 1.00). The mean
decrease in SAD after CLA treatment was 0.6 cm. Waist
The major ®nding in this randomised, controlled trial was
circumference was not signi®cantly different after 4 weeks
that CLA supplementation appeared to reduce abdominal
compared to placebo (P 0.51). However, the CLA group
adipose tissue in obese middle-aged men as indicated by a
experienced a signi®cant mean decrease in waist circumfer-
signi®cant decrease in SAD. It is possible that the decrease in
ence with 1.4 cm (P ` 0.01), while in the placebo group the
SAD represents a preferential loss of visceral fat.17±19,31,32
mean decrease (0.7 cm) was not signi®cant (P 0.08). WHR
However, this assumption needs con®rmation by computed
followed a similar pattern as waist circumference, with a
tomography (CT) which is superior to SAD in the measure-
signi®cant decrease only in the CLA group (P ` 0.01),
ment of visceral fat. SAD is a valid measure of both intra- and
although without difference between groups (P 0.20).
extra-abdominal fat,33 suggesting that CLA may have an
Mean body weights were slightly decreased (non-signi®cant)
effect on total abdominal adipose tissue. Within the CLA
to a similar degree after CLA and placebo with 0.3 and 0.4 kg,
group the decrease in abdominal fat was signi®cant for all
respectively (data not shown) with no signi®cant difference
measures of abdominal obesity, although there was no sta-
between the groups (P 0.79). This pattern was also true for
tistically signi®cant difference in changes of waist circum-
BMI without any signi®cant mean difference between the
ference or WHR between the two groups (Table 2). The
absensce of any statistical changes or differences in BMIsuggests a reduction in abdominal fat rather independentof total obesity. The reduction of body fat as suggested by the
decrease in SAD, is in concert with previous animal data that
There were no signi®cant differences between groups in
showed a reduced proportion of body fat after CLA treat-
cardiovascular risk factors (Table 2). HDL was increased in
ment.1±5 Moreover, the current ®nding is in agreement with
both groups, signi®cantly for the placebo group only
a recent controlled trial in healthy normal weight men and
(P ` 0.01). Plasma glucose was also signi®cantly increased
women.34 In that trial, the CLA-supplemented group experi-
in both groups. No signi®cant changes were detected in
enced reduced body fat, as measured by bioelectric impe-
dance analysis and skinfold techniques.
Conjugated linoleic acid and abdominal obesity
New data indicates that SAD has higher reliability (a lower
results on CLA and lipolysis are in agreement with the
intra-observer variation and a higher intra-class correlation)
®nding that CLA increased energy expenditure and fat
as compared to other anthropometrics, independent of
BMI.35 The high reliability and low degree of measurement
Regarding, a possible thermogenic effect of CLA, skeletal
error of SAD have been reported by others in a previous
tissue analyses of uncoupling protein (UCP) gene expression
study.36 To minimise measurement errors in the present trial,
in prediabetic ZDF-rats have showed an increased brown
there was a strong emphasis put on accurate assessment of
adipose tissue UCP-2mRNA expression in CLA fed rats com-
anthropometry, which was performed by one trained inves-
pared to controls.49 This ®nding may also be related to the
tigator in an identical fashion at both clinical examinations.
loss of body fat in animals. Interestingly, possible PPAR-g
Previous studies that used CT, suggest that visceral fat is
ligands such as CLA and thiazolidinediones have recently
highly correlated to metabolic risk factors as compared to
been reported to induce gene expression of UCP2 isoforms in
other fat depots.37±40 However, in contrast to animal
both skeletal muscle and adipose tissue.50 Moreover, there
data,10,12,13 no differences between the groups in cardiovas-
are also relevant data on the molecular level that give
cular risk factors were detected in the present trial. If abdom-
support to CLA as being a ligand of two isoforms of PPARs,
inal fat decreases after CLA, one would expect some parallel
both having important function in energy and adipose tissue
improvements in fasting glucose and insulin levels, which
metabolism. First, CLA is, in contrast to linoleic acid, a
were not seen in the current study. In contrast, both plasma
potent ligand and activator of peroxisome proliferator acti-
glucose and insulin tended to rise slightly within both
vating receptor alpha (PPAR-a),51,52 which pivotal role in
groups. Because the increase in these variables occurred in
obesity and lipid metabolism has been described in trans-
both study groups it is dif®cult to evaluate the importance of
genic mice,53 although the effects of PPAR-a activators on
these ®ndings. DeLaney et al showed that CLA-fed mice
human adipose tissue are still unknown.
experienced a rapid decrease in body fat accumulation (sig-
Second, it was previously reported that CLA activates
ni®cant after only 2 weeks of treatment), with the visceral
PPAR-g response elements in vitro.10 Since PPAR-g genes
depots being the most sensitive to CLA, which was accom-
seem to regulate both metabolic functions and adipose
panied by an increase in fasting insulin levels as compared to
tissue development,54 it is interesting to note that the
controls.41 They speculated that CLA may deteriorate pheri-
mRNA levels of PPAR-g are subjected to regional variation
pheral insulin dependent glucose disposal, as a consequence
in adipose tissue,55 with different sensitivity to the fat-cell
of increased lipolysis and fatty acid oxidation according to
differentiation in response to PPAR-activators.56 In clinical
the Randle glucose-fatty acid cycle,42 or by yet unknown
trials, the PPAR-g agonist troglitazone was found to markedly
decrease visceral fat in type 2 diabetic patients, withoutaffecting subcutaneous fat or BMI.57,58 Thus, it is temptingto speculate that the reduced SAD in the current trial might
CLA and effects on adipose tissue Ð possible mechanisms
be related to an effect of CLA on PPARs.
The mechanisms behind a possible fat reducing effect of CLA
Some limitations of this study need to be adressed. First,
are currently unknown, although there are some clues from
the limited sample size does not exclude the possibility that
in-vitro data and experimental animal models. Locally
the observed decrease in SAD occurred by chance, although
synthesized prostaglandins (PGs) may have antilipolytic
we did calculate con®dence intervals to provide some com-
effects in human adipose tissue.43 In vitro evidence have
plementary information about the power of the study, there-
indicated an inhibitory effect of CLA on PGE2 production,44
fore the ®ndings need to be con®rmed by CT measurements
a prostaglandin with anti-lipolytic effects in vitro.45,46 Thus,
in future studies. If CLA indeed has an affect on abdominal
the modulation of PG production by CLA supplementation
fat, it would be interesting to further study glucose and
may contribute to increased lipolysis of adipose tissue. Park
insulin metabolism after CLA administration. We are at
et al suggested an enhanced noradrenaline-induced lipolysis
present investigating the effect of CLA on obesity-related
and hormone-sensitive lipase activity, with an accompany-
insulin resistance in a larger trial which will provide informa-
ing fatty acid oxidation in skeletal muscle, due to increased
tion about the possible effect of CLA on glucose metabolism.
activity of carnitine palmitoyltransferase after CLA treat-ment.1 More recent data con®rm these in vitro effects ofCLA on lipolysis, lipoprotein lipase (LPL) activity and intra-
cellular accretion of triglycerides and glycerol.47 It has been
In conclusion, in men with marked abdominal visceral
described that visceral fat cells in abdominally obese men
obesity, CLA supplementation for 4 weeks may reduce
seem to have a greater ability to mobilise fatty acids than
abdominal fat as indicated by a signi®cant reduction in
subcutaneous fat cells, in response to cathecholamines.14,48
SAD. However, many questions remain unanswered. The
One might postulate that dietary CLA, as a possible inducer
fact that the decrease in SAD occurred without concomitant
of a cathecolamine-related lipolysis as shown in vitro by Park
improvements in related metabolic variables also indicates
et al,1 could cause a selective reduction of visceral fat,
that the results of the current trial must be interpreted with
indirectly measured as SAD in the present trial. The in vitro
caution. Nevertheless, because abdominal obesity is a strong
Conjugated linoleic acid and abdominal obesity
risk factor these results are interesting, and further trials with
16 Smedman AEM, Gustafsson I-B, Berglund LGT, Vessby BOH.
a larger number of subjects and performed during longer
Pentadecanoic acid in serum as a marker for intake of milk fat:
relations between intake of milk fat and metabolic risk factors.
time periods are needed to determine if CLA may be a safe
and effective antiobesity agent in subjects with abdominal
17 Kvist H, Chowdhury B, GrangaÊrd U, TyleÂn U, SjoÈstroÈm L. Total
and visceral adipose-tissue volumes derived from measurements
with computed tomography in adult men and women: predictive
equations. Am J Clin Nutr 1988; 48: 1351 ± 1361.
18 Van der Kooy K, Leenen R, Seidell JC, Deurenberg P, Visser M.
Abdominal diameters as indicators of visceral fat: comparison
We thank the staff at the laboratory of the Department of
between magnetic resonance imaging and anthropometry. Br J
Geriatrics for biochemical analysis of samples. We also would
19 SjoÈstroÈm L, LoÈnn L, Chowdbury B. The sagittal diameter is a valid
like to thank Natural Lipids Ltd AS, Hovebygda, Norway, for
marker of visceral adipose tissue volume. In: Angel A, Anderson
kindly supplying supplements used in this study. This study
H, Bouchard C, Lau L, Leiter L, Mendelson R (eds). Progress in
was supported by the Swedish Medical Research Council
obesity research VII. John Libbey: London; 1996. pp 309 ± 319.
20 Pouliot MC, DespreÂs JP, Lemieux S Moorjani S, Bouchard C,
Tremblay A, Nadeau A, Lupien PJ. Waist circumference and
sagittal diameter: best simple anthropometric indexes of abdom-
inal visceral adipose tissue accumulation and related metabolic
cardiovascular risk factors risk in men and in women. Am J
1 Park Y, Albright KJ, Liu W, Storkson JM, Cook ME, Pariza MW.
Effect of conjugated linoleic acid on body composition in mice.
21 Richelsen B, Pedersen SB. Associations between different anthro-
pometric measurements of fatness and metabolic risk parameters
2 West DB, DeLany JP, Camet PM, Blohm F, Truett AA, Schimeca JA.
in non-obese, healthy, middle-aged men. Int J Obes Relat Metab
Effects of conjugated linoleic acid on body fat and energy meta-
bolism in the mouse. Am J Physiol 1998; 275 (Regulatory Inter-
22 OÈhrvall M, Berglund L, Vessby B. Sagittal abdominal diameter
grative Comp Physiol 44): R667 ± R672.
compared with other anthropometric measurements in relation
3 Dugan MER, Aalhus JL, Shaefer AL, Kramer JKG. The effects of
to cardiovascular risk. Int J Obes Relat Metab Disord 2000; 24: 497 ±
conjugated linoleic acid on fat to lean repartitioning and feed
conversion in pigs. Can J Anim Sci 1997; 77: 723 ± 725.
23 Kahn HS, Austin H, Williamson DF, Arensberg D. Simple anthro-
4 Dunshea FR, Ostrowska E, Muralitharan M, Cross R, Bauman DE,
pometric indices associated with ischemic heart disease. J Clin
Pariza MW, Skarie C. Dietary conjugated linoleic acid decreases
back fat in ®nisher gilts. J Anim Sci 1998; 76(Suppl 1): 1998.
24 Gustat J, Elkasabany AM, Srinivasan SS, Berenson GS. The use of
5 Ostrowska E, Muralitharan M, Cross RF, Bauman DE, Dunshea FR.
abdominal height (sagittal diameter) in predicting cardiovascular
Dietary conjugated linoleic acid increases lean tissue and decrease
risk factors Ð The Bogalusa Heart Study. Circulation 1998;
fat deposition in growing pigs. J Nutr 1999; 129: 2037 ± 2042.
6 Kepler CR, Hirons KP, McNeill JJ, Tove SB. Intermediates and
25 Seidell JC, Andres R, Sorkin JD, Muller DC. The sagittal waist
products of the bihydrogenation of linoleic acid by Butyrivibrio
diameter and mortality in men: the Baltimore Longitudinal Study
®brisolvens. J Biol Chem 1966; 245: 3612 ± 3620.
on Aging. Int J Obes Relat Metab Disord 1994; 18: 61 ± 67.
7 Chin SF, Liu W, Storkson JM, Ha YL, Pariza MW. Dietary sources of
26 Van Staveren WA, De Boer JO, Burema J. Validity and reproduci-
conjugated dienoic isomers of linoleic acid, a newly recognized
bility of dietary history method estimating the usual food intake
class of anticarcinogens. J Food Comp Anal 1992; 5: 185 ± 197.
during the month. Am J Clin Nutr 1985; 42: 554 ± 559.
8 Britton M, Fong C, Wickens D, Yudkin J. Diet as a source of
27 Becker W. Befolkningens kostvanor och naÈringsintag i Sverige 1989.
phospholipid esteri®ed 9, 11-octadecadinoic acid in humans. Clin
Metod och resultatanalys. (Food habits and nutrient intake in
Sweden 1989. Methods and results). Statens Livsmedelsverk:
9 Jiang J, Wolk A, Vessby B. Relation between the intake of milk fat
and the occurrence of conjugated linoleic acid in human adipose
28 Jiang J. Conjugated linoleic acid: occurrence, oxidation and production
tissue. Am J Clin Nutr 1999; 70: 21 ± 27.
by dairy starter cultures (dissertation). Swedish University of Agri-
10 Houseknecht K, Vanden Heuvel JP, Moya-Camarena SY, Portocar-
rero CP, Peck LW, Nickel KP, Belury MA. Dietary conjugated
29 World Health Organization. The use and interpretation of anthro-
linoleic acid normalizes impaired glucose tolerance in zucker
pometry. Report of a WHO Expert Committee on Physical Status.
diabetic fatty faafa rat. Biochem Biophys Res Commun 1998; 244:
WHO Technical Report Series. no. 854, 1995. WHO: Geneva.
30 Seigler L, Wu WT. Separation of serum high-density lipoprotein
11 Gavino VC, Gavino G, Leblanc MJ, Tuchweber B. An isomeric
for cholesterol determination: ultracentrifugationn vs precipita-
mixture of conjugated linoleic acid but not pure cis-9, trans-11-
tion with sodium phosphotunstate and magnesium chloride.
octadecadienoic acid affects body weight gain and plasma lipids
in hamsters. J Nutr 2000; 130: 27 ± 29.
31 Keller C, Chintapalli K, Lancaster J. Correlation of anthropome-
12 Lee KN, Kritchevsky D, Pariza MW. Conjugated linoleic acid and
try with CT in Mexican American-women. Res Nurs Health 1999;
atherosclerosis in rabbits. Atherosclerosis 1994; 108: 19 ± 25.
13 Nicolosi RJ, Rogers EJ, Kritchevsky D, Schimeca, Huth PJ. Dietary
32 Zamboni M, Turcato E, Armellini F, HS Kahn, Zivelonghi A,
conjugated linoleic acid reduces plasma lipoproteins and early
Santana H, Bergamo-Andreis IA, Bosello O. Sagittal abdominal
aortic atherosclerosis in hypercholesterolemic hamsters. Artery
diameter as a practical predictor of visceral fat. Int J Obes Relat
14 BjoÈrntorp P. Visceral obesity: a civilization syndrome. Obes Res
33 Clasey JL, Bouchard C, Teates CD, Riblett JE, Thorner MO, Hart-
man ML, Weltman A. The use of anthropometric and dual-energy
15 DespreÂs JP. The insulin resistance-dyslipidemic syndrome of visc-
X-ray absorptiometry (DXA) measures to estimate total abdom-
eral obesity: effect on patients risk. (Review.) Obes Res 1998;
inal and abdominal visceral fat in men and women. Obes Res
Conjugated linoleic acid and abdominal obesity
34 Smedman A, Vessby B. Conjugated linoleic acid reduces the body
47 Park Y, Storkson JM, Albright KJ, Liu W, Pariza MW. Evidence
fat content in humans. (Abstract.) Chem Phys Lipids 1999; 101:
that the trans-10, cis-12 isomer of conjugated linoleic acid
induces body composition changes in mice. Lipids 1999; 34:
35 Nordhamn K, SoÈdergren E, Olsson E, KarlstroÈm B, Vessby B,
Berglund L. Reliability of anthropometric measurements in over-
48 Reynisdottir S, Ellerfeldt K, Wahrenberg H, Lithell H, Arner P.
weight and lean subjects: consequences for correlations between
Multiple lipolysis defects in the insulin resistance (metabolic)
anthropometric and other variables. Int J Obes Relat Metab Disord
syndrome. J Clin Invest 1994; 93: 2590 ± 2599.
49 Portocarrero CP, Bauman DE, Barbano DM, Zierath JR,
36 Williamson DF, Kahn HS, Worthman CM, Burnette JC, Russel
Houseknecht KL. Regulation of UCP1 and UCP2 gene expression
CM. Precision of recumbent anthropometry. Am J Hum Biol 1993;
by dietary conjugated linoleic acid (CLA) in zucker diabetic
fatty (ZDF) rats. (Abstract.) American Diabetes Association
37 MaÊrin P, Andersson B, Ottosson M, Olbe L, Kvist H, Holm G,
(ADA) annual meeting, San Diego, 17 ± 24 June, 1999, Abstract
SjoÈstroÈm L, BjoÈrntorp P. The morphology and metabolism of
intra abdominal adipose tissue in men. Metabolism 1992; 41:
50 Camirand A, Marie V, Rabelo R, Silva JE. Thiazolidinediones
stimulate uncoupling protein-2 expression in cell lines represent-
38 Kissebah AH, Peiris AN, Evans D. Mechanisms associating body
ing white and brown adipose tissues and skeletal muscle. Endo-
fat distribution to glucose intolerance and diabetes mellitus:
window with a view. Acta Med Scand 1989; 723(Suppl): 79 ± 89.
51 Belury MA, Moya-Camarena SY, Liu K, Vanden Heuvel JP. Dietary
39 Fujioka S, Matsuzawa Y, Tokunaga K, Tarui S. Contribution of
conjugated linoleic acid induces peroxisome-speci®c enzyme
intraabdominal fat accumulation to the impairment of glucose
accumulation and ornithine decarboxylase activity in mouse
and lipid metabolism in human obesity. Metabolism 1987; 36:
liver. J Nutr Biochem 1997; 8: 579 ± 584.
52 Moya-Camarena SY, Heuvel JP, Blanchard SG, Leesnitzer LA,
40 Lemieux S, PrudõÂhomme D, Nadeau A, Tremblay A, Bouchard C,
Belury MA. Conjugated linoleic acid is a potent naturally occur-
DespreÂs JP. Seven-year changes in body fat and visceral adipose
ring ligand and activator of PPARalpha. J Lipid Res 1999; 40:
tissue in women. Association with indexes of plasma glucose-
insulin homeostasis. Diabetes Care 1996; 19: 983 ± 991.
53 Costet P, Legendre C, More J, Edgars A, Galtier P, Pineau T.
41 DeLany JP, Blohm F, Truett AA, Scimeca JA, West DB. Conjugated
Peroxisome proliferator-activated receptor a-isoform de®ciency
linoleic acid rapidly reduces body fat content in mice without
leads to progressive dyslipidemia with sexually dimorphic obesity
affecting energy intake. Am J Physiol 1999; 276(Regulatory Inte-
and steatosis. J Biol Chem 1998; 273: 29577 ± 29585.
grative Comp Physiol 45): R1172 ± R1179.
54 Spiegelman BM, Flier JS. Adipogenesis and obesity: rounding out
42 Randle P, Garland P, Hales C, Newsholme E. The glucose-fatty
the big picture. Cell 1996; 87: 377 ± 389.
acid cycle: its role in insulin sensitivity and the metabolic
55 Lefebvre AM, Laville M, Vega N, Riou JP, Gaal LV, Auwerx J, Vidal
disturbances of diabetes mellitus. Lancet 1963; i: 785 ± 789.
H. Depot-speci®c differences in adipose tissue gene expression in
43 Arner P. Differences in lipolysis between human subcutaneous
lean and obese subjects. Diabetes 1998; 47: 98 ± 103.
and omental adipose tissues. Ann Med 1995; 27: 435 ± 438.
56 Adams M, Montague CT, Prins JB, Holder J, Smith SA, Sanders L,
44 Kavanaugh CJ, Liu KL, Belury MA. Effect of dietary conjugated
Digby JE, Sewter CP, Lazar MA, Chatterjee KK, O'Rahilly S.
linoleic acid on phrbol ester-induced PGE2 production and
Activator of peroxisome proliferator-activated receptor gamma
hyperplasia in mouse epidermis. Nutr Cancer 1999; 33: 132 ± 138.
have depot speci®c effects on human preadipocyte differentia-
45 Richelsen B, Pedersen SB, Moller-Pedersen T, Bak JF. Regional
tion. J Clin Invest 1997; 100: 3149 ± 3153.
differences in triglyceride breakdown in human adipose tissue:
57 Kelly IE, Han TS, Walsh K, Lean MEJ. Effects of a thiazolidine-
effects of catecholamines, insulin, and prostaglandin E2. Metabo-
dione compound on body fat distribution of patients with type 2
diabetes. Diabetes Care 1999; 22: 288 ± 293.
46 Gaskins HR, Hausman DB, Martin RJ, Hausman GJ. Evidence for
58 Mori Y, Murakawa Y, Okada K, Horikoshi H, Yokoyama J, Tajima
abnormal prostaglandin synthesis in obese zucker rat cell cul-
N, Ikeda Y. Effect of troglitazone on body fat distribution in type
tures. J Nutr 1989; 119: 458 ± 462.
2 diabetic patients. Diabetes Care 1999; 22: 908 ± 912.
ASTHMA CARE TIPS Asthma is a very common chronic illness in children. Fortunately many children with asthma will outgrow their illness and their need for medication. Until they do, and for the few who have more serious asthma, it is important to understand: • What are the things that trigger my asthma? How can I avoid the triggers?• What are my medicines and how do I use each one?•
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