Garlic as
a phytogenic lipid-lowering drug - A review of
clinical trails with standardized garlic powder
preparations
Brosche T.; Platt D.
Lehrstuhl fur Innere Medizin - Gerontologie der
Universitat, Heimerichstrasse 58, W-8500 Nurnberg
90 Germany, Federal Republic of
Fortschr. Med. (Germany, Federal Republic of),
1990, 108/36 (49-54)
Garlic (Allium sativum L.) is a commonplace
drug. It is now available in the form of dragees
made of garlic powder, standardized to 1.3%
alliin. The lipid-lowering potential of such
preparations has not been reviewed yet. In 7 out
of 8 studies, including over 500 patients, a daily
dose of 0.6 g to 0.9 g garlic powder reduced
plasma cholesterol and triglyceride levels by 5 to
20 percent. The metabolic mechanisms of these
reductions are not known.
Effect of
an odor-modified garlic preparation on blood
lipids
Lau B.H.S.; Lam F.; Wang-Cheng R.
Department of Microbiology, School of Medicine,
Loma Linda University, Loma Linda, CA 92350 USA
Nutr. Res. (USA), 1987, 7/2 (139-149)
The effect of an odor-modified liquid garlic
extract on blood lipids was evaluated in human
subjects over a six month period. Lowering of
cholesterol , triglycerides, low density and very
low density lipoproteins (LDL, VLDL) with rise of
high density lipoprotein (HDL) was observed in the
majority of subjects who took garlic extract; the
effect was clearly more significant than with
subjects taking placebo. Garlic extract did not
significantly influence the levels of cholesterol
and triglycerides in subjects whose initial
cholesterol levels were relatively low. Of special
interest was the initial rise of cholesterol ,
triglycerides, and LDL/VLDL with garlic
supplementation, suggesting possible mobilization
of tissue lipids into the circulation during this
phase of garlic ingestion. This study confirms
previous reports of lowering cholesterol and
triglycerides using various garlic preparations.
Furthermore, it suggests that odor-modified garlic
extract may be used in conjunction with dietary
modification for control of hyperlipidemia.
Oral guar
gum treatment of intrahepatic cholestasis and
pruritus in pregnant women: effects on serum
cholestanol and other non- cholesterol
sterols.
Gylling H; Riikonen S; Nikkila K; Savonius H;
Miettinen TA
Department of Medicine, University of Helsinki,
Finland.
Eur J Clin Invest (England) May 1998, 28 (5)
p359-63
BACKGROUND: Our aim was to investigate whether
intestinal binding of bile acids by guar gum, a
dietary fibre, relieves cholestasis and pruritus
in intrahepatic cholestasis of pregnancy.
METHODS: Forty-eight pregnant women with
cholestasis and pruritus were randomized
double-blind to guar gum and placebo until the
time of delivery, and 20 healthy pregnant women
were used as control subjects. The pruritus score
and serum bile acids, lipids and non-cholesterol
sterols were measured at baseline, at least 2
weeks after treatment, just before delivery and up
to 4 weeks after delivery.
RESULTS: The increase in serum bile acids and
worsening of pruritus were prevented by guar gum
in relation to placebo (P < 0.05). Serum
cholesterol was unchanged, but increased
cholesterol precursor sterol values suggested that
cholesterol synthesis was increased by guar gum.
Serum cholestanol proportion, an indicator of
cholestasis, was related to pruritus but was
unaffected by guar gum.
CONCLUSION: We conclude that in intrahepatic
cholestasis of pregnancy and pruritus, guar gum
treatment is beneficial in relieving pruritus,
even although indicators of cholestasis are only
partially reduced.
Increasing amounts of dietary fiber
provided by foods normalizes physiologic response
of the large bowel without altering calcium
balance or fecal steroid excretion.
Haack VS; Chesters JG; Vollendorf NW; Story JA;
Marlett JA
Department of Nutritional Sciences, University of
Wisconsin-Madison, 53706, USA.
Am J Clin Nutr (United States) Sep 1998, 68 (3)
p615-22
Nine healthy, young men consumed constant diets
to determine selected large-bowel, serum
cholesterol and triacylglycerol, and calcium
balance responses to 3 amounts of fiber provided
by a mixture of fruit, vegetables, and grains. The
diets, each consumed for 1 mo, contained 16, 30,
and 42 g total fiber /d, of which 2.9, 4.8, and
7.7 g, respectively, was soluble. Mean daily wet
and dry stool weights increased with each fiber
addition. The first fiber addition increased
defecation frequency and decreased fecal pH, bile
acid concentration, and neutral steroid
concentration; the second addition had no further
effect. Mean weight of each defecation and stool
moisture did not increase and serum cholesterol
and triacylglycerol concentrations, calcium
balance, and gastrointestinal transit time did not
decrease as fiber intake increased. We conclude
that 1) fiber provided by a mixed-food diet
increases stool weight as effectively as does
wheat or oat bran; 2) even high amounts of dietary
fiber do not change transit time or defecation
frequency if they are already approximately 1 and
2-3 d, respectively; 3) food patterns consistent
with the food pyramid and incorporating legumes
and whole grains are necessary to achieve
recommended fiber intakes of 20-35 g/d, even if
energy intake is > 12.55 MJ (3000 kcal); 4)
soluble fiber provided by a mixture of whole foods
has no effect on serum cholesterol concentrations
or output of fecal bile acids; and 5) mixed-food
fiber has little effect on calcium balance when
calcium intakes are high (> or = 1.5 g/d).
[The use
of dietary fiber as natural enterosorbents in
diseases of the hepatobiliary system]
Berezovs'kyi VIa; Lytova IH; Dynnyk OB;
Korychens'kyi OM; Pavlyk IV
Lik Sprava (Ukraine) Mar-Apr 1998, (2) p80-2
Intensity was studied of sorption of
cholesterol , bile acids, and phospholipids by
cereals food fibre in samples of vesicular and
hepatic bile. Intensive absorption has been shown
of these fractions by food fibres. Clinical
observation over 92 patients with chronic
noncalculous cholecystitis confirmed the
beneficial effect of cereals food fibre.
Validity
and reproducibility of a food frequency
questionnaire to assess dietary intake of women
living in Mexico City.
Hernandez-Avila M; Romieu I; Parra S;
Hernandez-Avila J; Madrigal H; Willett W
Instituto Nacional de Salud Publica, Cuernavaca,
Morelos, Mexico.
Salud Publica Mex (Mexico) Mar-Apr 1998, 40 (2)
p133-40
OBJECTIVE: To assess the reproducibility and
validity of a 116 item semi-quantitative food
frequency questionnaire (FFQ), designed to assess
the relation between dietary intake and chronic
diseases.
MATERIAL AND METHODS: To test the
reproducibility of the FFQ questionnaire, the FFQ
was administered twice to 134 women residing in
Mexico City at an interval of approximately one
year; to assess the validity we compared results
obtained by the FFQs with those obtained by four
4-day 24-hour recalls at three month intervals.
Validity and reproducibility were evaluated using
regression analysis and Pearson and intraclass
correlation coefficients of log-e and
calorie-adjusted nutrient scores.
RESULTS: Mean values for intake of most
nutrients assessed by the two food frequency
questionnaires were similar. However, means for
the 24-hr recall were significantly lower.
Intraclass correlation coefficients for nutrient
intakes, assessed by questionnaires, administered
one year apart, ranged from 0.38 for cholesterol
to 0.54 for crude fiber. Correlation coefficients
between energy-adjusted nutrient intakes, measured
by diet recalls, and the first FFQ ranged from
0.12 for polyunsaturated fatty acids to 0.67 for
saturated fatty acids. Regression coefficients
between 24-hr recall and FFQ,s were all
significant were significant for all nutrients,
except for polyunsaturated fat, folic acid,
vitamin E and Zinc.
CONCLUSIONS: These data indicate that this
semi-quantitative FFQ is reproducible and provides
a useful estimate by which to categorize
individuals by level of past nutrient intake.
However, its application outside Mexico City or in
different age and gender populations will require
additional modifications and validation
efforts.
Oxidized
LDL promotes vascular endothelial cell pinocytosis
via a prooxidation mechanism.
Chow SE; Lee RS; Shih SH; Chen JK
Department of Biology, National Taiwan Normal
University, Taipei.
FASEB J (United States) Jul 1998, 12 (10)
p823-30
Human low density lipoprotein (LDL) is prepared
in the presence of antioxidants and is oxidized to
different levels (measured by thiobarbituric acid
reactive substance) with copper ion. The effects
of unoxidized LDL and oxidized LDL (ox-LDL) on
stress fiber formation, cell membrane ruffling,
and pinocytosis (measured by [14C]sucrose uptake)
in cultured human umbilical cord vein endothelial
cells (EC) are compared. We show that at a
concentration range of 100 to 200 microg
cholesterol /ml, both unoxidized LDL and ox-LDL
promote EC elongation and stress fiber formation,
but the effect by the latter is more prominent
when compared at the same dose range. In addition,
ox-LDL also induces EC membrane ruffling and
promotes pinocytosis. These effects are positively
correlated with the extent of LDL oxidation and
depend on the dose of ox-LDL. Ox-LDL-promoted
membrane ruffling and pinocytosis are effectively
blocked by brief preexposure of the cells to
antioxidants. In contrast, stress fiber formation
is not affected by antioxidant pretreatment.
Although unoxidized LDL also promotes [14C]sucrose
uptake, it is less potent than ox-LDL and
significantly higher concentrations are required
to produce a detectable effect. Unlike ox-LDL,
unoxidized LDL-enhanced pinocytosis is not
accompanied by the appearance of membrane
ruffling; therefore, they may act via different
mechanisms. Elevated pinocytosis may increase
transcytotic activity of the endothelium, leading
to an increased influx of plasma components such
as LDL into the subendothelial space.
[Dietary
fibers in diet therapy]
Pogozheva AV
Vopr Pitan (Russia) 1998, (1) p39-42
Dietary fibers belong to the group of polymeric
compounds with different chemical origin. They
play an important part in functioning of number of
organs and body systems and in the first place
influence upon the function of large intestine.
Having ability to retain water, they accelerate an
intestine transit and peristalsis of large
intestine, and are the stool forming factor.
Dietary fibers adsorb many bile acids,
metabolites, toxins and electrolytes and promote
detoxification of organism. Due to ionchange
properties dietary fibers are capable to remove
ions of heavy metals and radionuclides. Dietary
fibers render positive action during the
functional diseases of large intestine, reduce
blood cholesterol concentration, have
hypolipidemic effect and can be used for
prophylactic and therapy of cardiovascular and
other diseases.
Definition of healthy eating in the
Spanish adult population: a national sample in a
pan-European survey.
Martinez-Gonzalez MA; Lopez-Azpiazu I; Kearney
J; Kearney M; Gibney M; Martinez JA
Department of Epidemiology and Public Health,
University of Navarra, Pamplona, Spain.
Public Health (England) Mar 1998, 112 (2)
p95-101
A national survey was carried out to find out
how the Spanish adult population defined 'healthy
eating'. Consumers were asked to describe in their
own words what 'healthy eating' means to them. The
sample included 1009 Spanish subjects over 15 y of
age selected by a multietapic procedure. This
study belongs to the Spanish partnership in a
pan-European survey about attitudes to food,
nutrition and health coordinated by the Institute
of European Food Studies of Dublin. The results
were shown as the percentages of the sample who
gave one of the five most frequently mentioned
descriptions ('more vegetables', 'balanced diet',
'more fruit', 'less fat' and 'more fish') and the
distribution of responses by age, sex, region,
socio-economic level and education level. A
multivariable logistic regression model was fitted
to assess the characteristics independently
related to the use of the definition 'balance and
variety' for healthy eating. The majority of the
Spanish people defined 'healthy eating' as a diet
with 'more vegetables' as the main description.
Other descriptions commonly mentioned were 'less
fat', 'more fruit', 'more fish', and 'more lean
meat'. A higher age was associated with a lower
likelihood of mentioning the concept of balanced
diet. A higher educational level was also
independently and strongly related to a higher
prevalence of this definition. Differences between
men and women showed only borderline significance.
Our results suggest the need to improve
nutritional education about fiber, low fat and
cholesterol. It would be interesting to develop
strategies in Spain to educate people on a
definition of 'healthy eating' based upon 'balance
and variety'.
Dietary
sources of nutrients among US adults, 1989 to
1991.
Subar AF; Krebs-Smith SM; Cook A; Kahle LL
National Cancer Institute, Applied Research
Branch, Bethesda, Md. 20892-7344, USA.
J Am Diet Assoc (United States) May 1998, 98 (5)
p537-47
OBJECTIVE: To identify major food sources of 27
nutrients and dietary constituents for US
adults.
DESIGN: Single 24-hour dietary recalls were
used to assess intakes. From 3,970 individual
foods reported, 112 groups were created on the
basis of similarities in nutrient content or use.
Food mixtures were disaggregated using the US
Department of Agriculture (USDA) food grouping
system.
SUBJECTS/SETTING: A nationally representative
sample of adults aged 19 years or older (n =
10,638) from USDA's 1989-91 Continuing Survey of
Food Intakes by Individuals.
ANALYSES PERFORMED: For each of 27 dietary
components, the contribution of each food group to
intake was obtained by summing the amount provided
by the food group for all respondents and dividing
by total intake from all food groups for all
respondents.
RESULTS: This article updates previous work and
is, to the authors' knowledge the first to provide
such data for carotenes, vitamin B-12, magnesium,
and copper. Beef, yeast bread, poultry, cheese,
and milk were among the top 10 sources of energy,
fat, and protein. The following other major
sources also contributed more than 2% to energy
intakes: carbohydrate: yeast bread, soft
drinks/soda, cakes/cookies/ quick
breads/doughnuts, sugars/syrups/jams, potatoes
(white), ready-to-eat cereal, and pasta; protein:
pasta; and fat: margarine, salad
dressings/mayonnaise, and cakes/ cookies/quick
breads/doughnuts. Ready-to-eat cereals, primarily
because of fortification, were among the top 10
food sources for 18 of 27 nutrients.
APPLICATIONS/CONCLUSIONS: These analyses are
the most current regarding food sources of
nutrients and, because of disaggregation of
mixtures, provide a truer picture of contributions
of each food group.
Fruit
consumption, fitness, and cardiovascular health in
female adolescents: the Penn State Young Women's
Health Study.
Lloyd T; Chinchilli VM; Rollings N; Kieselhorst
K; Tregea DF; Henderson NA; Sinoway LI
Department of Obstetrics and Gynecology, The
College of Medicine and University Hospitals, The
Pennsylvania State University at The Milton S
Hershey Medical Center, Hershey 17033, USA.
tlloyd@psuhmc.hmc.psu.edu
Am J Clin Nutr (United States) Apr 1998, 67 (4)
p624-30
The objective of this study was to compare the
relations among nutrient intake, fitness, serum
antioxidants, and cardiolipoprotein profiles in
female adolescents. The study design was a
cross-sectional analysis of the Penn State Young
Women's Health Study. The present study was
performed with the entire cohort (n = 86) when
they were 17.1+/-0.5 y (x+/-SD) of age. Primary
measurements included cardiolipoprotein indexes,
serum antioxidants, nutrient intakes, aerobic
fitness, and percentage body fat. The cohort was
stratified by estimated maximal oxygen uptake
(VO2max) measurements and by percentage body fat.
The fifth quintile by estimated VO2max had
significantly lower percentage body fat, higher
athletic scores, higher fruit intake, lower total
serum cholesterol , and lower ratios of total
serum cholesterol to HDL cholesterol than members
of the first quintile. When the members of the
first and fifth quintiles by percentage body fat
were compared, the first quintile had
significantly lower weight, lower body mass index,
higher estimated VO2max, higher athletic scores,
lower ratios of total serum cholesterol to HDL
cholesterol , and higher fruit, carbohydrate, and
fiber intakes. Correlation analyses performed with
the data for the entire cohort showed fruit
consumption to be positively correlated with
estimated VO2max, and predicted VO2max to be
positively correlated with circulating
beta-carotene and alpha-tocopherol. This study
provided evidence that the positive associations
of exercise and fruit consumption with
cardiovascular health apply to female adolescents
as well as to adults.
Zinc
absorption, mineral balance, and blood lipids in
women consuming controlled lactoovovegetarian and
omnivorous diets for 8 wk.
Hunt JR; Matthys LA; Johnson LK
US Department of Agriculture, Agricultural
Research Service, Grand Forks Human Nutrition
Research Center, ND 58202-9034, USA.
Am J Clin Nutr (United States) Mar 1998, 67 (3)
p421-30
Zinc absorption, mineral balance, and blood
lipid concentrations were measured in 21 women
aged 33 +/- 7 y (range: 20-42 y) consuming
controlled lactoovovegetarian and nonvegetarian
diets for 8 wk each in a crossover design. The
lactoovovegetarian and nonvegetarian diets,
respectively, provided (by analysis) 973 and 995
mg Ca, 1.8 and 1.3 mg Cu, 367 and 260 mg Mg, 5.9
and 2.5 mg Mn, 1457 and 1667 mg P, 9.1 and 11.1 mg
Zn, and (by calculation) 40 and 16 g dietary fiber
, 2.5 and 0.8 mmol phytic acid, molar ratios of
phytate to Zn of 14 and 5, and millimolar ratios
of (phytate x Ca) to Zn of 344 and 111. Dietary
zinc absorption was measured by extrinsic isotopic
labeling and whole-body counting. Plasma
cholesterol , cholesterol fractions, and
lipoproteins were reduced 7-12% with the
lactoovovegetarian diet, consistent with
predictions based on dietary cholesterol and fat.
Blood pressure was unaffected. Calcium, copper,
magnesium, and phosphorus balances were not
different between diets; manganese balance tended
to be greater with the lactoovovegetarian diet (P
< 0.07). The lactoovovegetarian diet was
associated with a 21% reduction in absorptive
efficiency that, together with a 14% reduction in
dietary zinc, reduced the amount of zinc absorbed
by 35% (2.4 compared with 3.7 mg/d) and reduced
plasma zinc by 5% within the normal range. Zinc
balance was maintained with both diets. Although
there is a greater risk of zinc deficiency in
persons consuming lactoovovegetarian compared with
omnivorous diets, with inclusion of whole grains
and legumes zinc requirements can be met and zinc
balance maintained.
Long-term effects of consuming foods
containing psyllium seed husk on serum lipids in
subjects with hypercholesterolemia.
Davidson MH; Maki KC; Kong JC; Dugan LD; Torri
SA; Hall HA; Drennan KB; Anderson SM; Fulgoni VL;
Saldanha LG; Olson BH
Chicago Center for Clinical Research, IL 60610,
USA
mdavidson@cccr.com
Am J Clin Nutr (United States) Mar 1998, 67 (3)
p367-76
The effects of consuming foods containing 0
(control), 3.4, 6.8, or 10.2 g psyllium seed husk
(PSH)/d for 24 wk on the serum lipid profile were
assessed in this randomized, double-blind
controlled study. Men and women (n = 286) with
LDL- cholesterol concentrations between 3.36 and
5.68 mmol/L (130 and 220 mg/dL) were randomly
assigned to one of four treatment groups after
following a low-fat diet for > or = 8 wk. At
week 24, LDL cholesterol was 3% above baseline in
the control group. In the group consuming 10.2 g
PSH/d, LDL cholesterol remained below baseline
during treatment, with a value 5.3% below that of
the control group at week 24 (P < 0.05 compared
with the control group). No significant
differences were observed in HDL cholesterol or
triacylglycerol. Although modest, the effect of
10.2 g PSH/d on LDL cholesterol (relative to the
control) persisted throughout the 24-wk treatment
period, indicating potential for long-term
benefit.
Decreased serum total cholesterol
concentration is associated with high intake of
soy products in Japanese men and
women.
Nagata C; Takatsuka N; Kurisu Y; Shimizu H
Department of Public Health, Gifu University
School of Medicine, Gifu 500, Japan.
J Nutr (United States) Feb 1998, 128 (2)
p209-13
The relationship between soy product intake and
serum total cholesterol concentration was examined
in 1242 men and 3596 women who participated in an
annual health check-up program in Takayama City,
Japan, provided by the municipality in 1992. The
intake of soy products and various foods and
nutrients was assessed by a semiquantitative
food-frequency questionnaire. Blood samples were
collected from fasting subjects to measure the
serum total cholesterol concentration. A
significant trend (P for trend = 0. 0001) was
observed for decreasing total cholesterol
concentration with an increasing intake of soy
products in men after controlling for age, smoking
status and intake of total energy, total protein
and total fat. This negative trend (P for trend =
0.0001) was also noted in women after controlling
for age, menopausal status, body mass index and
intake of total energy and vitamin C. An
additional adjustment for physical activity,
coffee and tea consumption, and intake of
cholesterol , carbohydrates, fiber and vitamin E
did not change the results. These data suggest a
role for soy products in human cholesterol
homeostasis.
Cholesterol , phospholipid, and
protein changes in focal opacities in the human
eye lens.
Duindam JJ; Vrensen GF; Otto C; Greve J
Department of Morphology, The Netherlands
Ophthalmic Research Institute, Amsterdam.
Invest Ophthalmol Vis Sci (United States) Jan
1998, 39 (1) p94-103
PURPOSE: Focal opacities are signs of early
cataractogenesis in the human lens. They progress
slowly over a lifetime and may be precursors of
mature cataracts. The authors analyzed changes in
proteins, phospholipids, and cholesterol in these
opacities using in situ techniques: Raman
microspectroscopy, filipin cytochemistry for
cholesterol , and transmission electron microscopy
(TEM).
METHODS: Human lenses with verified focal
opacities were fixed in 1% paraformaldehyde. Slabs
with opacities were analyzed using confocal Raman
spectroscopy, then filipin Raman analysis of
cholesterol , and finally TEM.
RESULTS: Compared with normal fibers, opacities
consistently showed elevated levels of cholesterol
and aliphatic chains, increased phospholipid acyl
chain disorder, and changes in phospholipid
lateral packing. Disulfide bridges of specific
geometry (trans-gauche-trans) were found. Although
protein content was unchanged, compared with
normal fibers, aromatic amino acid content was
significantly lower. The hydrophobicity of
tyrosine residues showed a significant decrease,
and a change in the tryptophan indole ring angle
was found. The changes were abrupt and sharply
delineated focal opacities. TEM confirmed this
sharp boundary and showed that the opacities were
densely packed with vesicles of varying size and
electron density embedded in a homogenous
matrix.
CONCLUSIONS: The Raman and TEM analyses of
opacities showed that early cataractogenic events
led to disruption of fiber membranes, formation of
vesicles from the membrane constituents, and
protein changes. The aberrant morphology of the
membranes enveloping the focal opacities may have
segregated the affected fibers from the
surrounding normal tissue, thus explaining the
stationary or slowly progressing character of
these opacities.
A
low-viscosity soluble- fiber fruit juice
supplement fails to lower cholesterol in
hypercholesterolemic men and women
Davidson M.H.; Dugan L.D.; Stocki J.; Dicklin
M.R.; Maki K.C.; Coletta F. ; Cotter R.; McLeod
M.; Hoersten K.
M.H. Davidson, Chicago Center for Clinical
Research, Chicago, IL 60610 United States
Journal of Nutrition (United States), 1998,
128/11 (1927-1932)
This study was designed to determine whether a
soluble dietary fiber supplement containing gum
arabic and pectin in apple juice would lower serum
lipids in 110 hypercholesterolemic men and women.
Subjects were stabilized on an American Heart
Association Phase I Diet for 8 wk. Those with
elevated low density lipoprotein cholesterol
levels, despite dietary modification, continued to
follow the diet and were randomly assigned to
receive 720 mL/d of apple juice containing 0
(control), 5, 9 or 15 g of gum arabic and pectin
(4:1 ratio) for 12 wk, followed by a 6-wk apple
juice-only washout phase. Serum lipid profiles,
body weight and 3-day diet records were collected
at 3- wk intervals. No significant differences
among groups were observed in serum lipid
responses during treatment or washout. During the
treatment phase, mean serum total cholesterol and
triglyceride concentrations increased by 3.5 and
28.5%, respectively (all groups combined, P <
0.0001). The high density lipoprotein cholesterol
level did not change significantly from baseline
in any group. During washout, mean total
cholesterol concentration rose by an additional
2.4% (P < 0.05) compared with the value at the
end of the treatment period, suggesting that the
apple juice used to deliver the fiber supplement
may have contributed to the adverse changes
observed in the serum lipid profile. These
findings do not support the hypothesized
hypocholesterolemic effect of the gum
arabic/pectin (4:1) mixture studied, but do
underline the importance of selecting appropriate
vehicles for delivery of dietary fiber
mixtures.
Food
and nutrient intake of premenopausal female
vegetarians and omnivores in Finland
Outila T.; Karkkainen M.; Seppanen R.;
Lamberg-Allardt C.
Dr. C. Lamberg-Allardt, Dept. of Applied
Chem./Microbiology, Division of Nutrition,
University of Helsinki, PO Box 27, FIN-00014
Helsinki Finland
Scandinavian Journal of
Nutrition/Naringsforskning (Sweden), 1998, 42/3
(98-103)
We have investigated the food and nutrient
intake of five demi-vegans, six lacto-vegetarians
and fourteen omnivores, all females and aged 22-45
years, collecting a total of 42 dietary records
per person in 2-day periods during one year. The
yearly mean intakes of cereals, vegetables, fruits
and berries, dietary fibre and vitamin C were
higher and that of sugar, eggs, saturated fat and
cholesterol lower in the vegetarians than in the
omnivores. The intake of iron was higher in the
vegetarians, but their serum ferritin levels were
lower throughout the year than in the omnivores
indicating lower iron status in vegetarians. The
vegetarian diets provided practically no vitamin
D, which was reflected in a low serum
25-hydroxyvitamin-D concentration during spring,
but during summer concentrations increased to the
adequate level. Furthermore, the mean iodine
intake of vegetarians using minor amounts of dairy
products was below the recommended level. Thus,
the vegetarians had lower cholesterol , saturated
fat and higher carbohydrates and fibre intakes
than omnivores. However, seven of the eleven
vegetarians were iron deficient throughout the
year and six had serum 25-hydroxyvitamin-D
concentrations below reference values in the
winter.
Functional food science and the
cardiovascular system
Hornstra G.; Barth C.A.; Galli C.; Mensink
R.P.; Mutanen M.; Riemersma R.A.; Roberfroid M.;
Salminen K.; Vansant G.; Verschuren P.M.
Dr. G. Hornstra, Department of Human Biology,
Maastricht University, PO Box 616, NL-6200 MD,
Maastricht Netherlands
British Journal of Nutrition (United Kingdom),
1998, 80/Suppl. 1 (S113-S146)
Cardiovascular disease has a multifactorial
aetiology, as is illustrated by the existence of
numerous risk indicators, many of which can be
influenced by dietary means. It should be
recalled, however, that only after a
cause-and-effect relationship has been established
between the disease and a given risk indicator
(called a risk factor in that case), can modifying
this factor be expected to affect disease
morbidity and mortality. In this paper, effects of
diet on cardiovascular risk are reviewed, with
special emphasis on modification of the plasma
lipoprotein profile and of hypertension. In
addition, dietary influences on arterial
thrombotic processes, immunological interactions,
insulin resistance and hyperhomocysteinaemia are
discussed. Dietary lipids are able to affect
lipoprotein metabolism in a significant way,
thereby modifying the risk of cardiovascular
disease. However, more research is required
concerning the possible interactions between the
various dietary fatty acids, and between fatty
acids and dietary cholesterol. In addition, more
studies are needed with respect to the possible
importance of the postprandial state. Although in
the aetiology of hypertension the genetic
component is definitely stronger than
environmental factors, some benefit in terms of
the development and coronary complications of
atherosclerosis in hypertensive patients can be
expected from fatty acids such as alpha-linolenic
acid, eicosapentaenoic acid and docosahexaenoic
acid. This particularly holds for those subjects
where the hypertensive mechanism involves the
formation of thromboxane A2 and/or
alpha1-adrenergic activities. However, large-scale
trials are required to test this contention.
Certain aspects of blood platelet function, blood
coagulability, and fibrinolytic activity are
associated with cardiovascular risk, but causality
has been insufficiently proven. Nonetheless,
well-designed intervention studies should be
initiated to further evaluate such promising
dietary components as the various n-3 and n-6
fatty acids and their combination, antioxidants,
fibre, etc. for their effect on processes
participating in arterial thrombus formation.
Long-chain polyenes of the n-3 family and
antioxidants can modify the activity of
immunocompetent cells, but we are at an early
stage of examining the role of immune function on
the development of atherosclerotic plaques.
Actually, there is little, if any, evidence that
dietary modulation of immune system responses of
cells participating in atherogenesis exerts
beneficial effects. Although it seems feasible to
modulate insulin sensitivity and subsequent
cardiovascular risk factors by decreasing the
total amount of dietary fat and increasing the
proportion of polyunsaturated fatty acids,
additional studies on the efficacy of specific
fatty acids, dietary fibre, and low-energy diets,
as well as on the mechanisms involved are required
to understand the real function of these dietary
components. Finally, dietary supplements
containing folate and vitamins B6 and/or B12
should be tested for their potential to reduce
cardiovascular risk by lowering the plasma level
of homocysteine.
Lipid-
and glucose-lowering efficacy of Plantago Psyllium
in type II diabetes
Rodriguez-Moran M.; Guerrero-Romero F.;
Lazcano-Burciaga G.
Dr. F. Guerrero-Romero, Siqueiros 225 esq,
Durango CP 34000 Mexico
Journal of Diabetes and its Complications (United
States), 1998, 12/5 (273-278)
The beneficial effect of dietary fiber in the
management of type II diabetes is still
controversial and has not been totally
demonstrated. The purpose of this study was to
determine the plasma-lowering effects of 5 g
t.i.d. of Plantago Psyllium, as an adjunct to
dietary therapy, on lipid and glucose levels, in
patients with type II diabetes. Patients were
randomly selected from an outpatient clinic of
primary care to participate in a double-blind
placebo-controlled study in which Plantago
Psyllium or placebo was given in combination with
a low fat diet. One hundred twenty-five subjects
were included in the study that consisted in a
6-week period of diet counseling followed by a
6-week treatment period. Fasting plasma glucose,
total plasma cholesterol , LDL cholesterol , HDL
cholesterol and triglyceride levels were measured
every 2 weeks. The test products (Psyllium or
placebo) were supplied to subjects in identically
labeled foil packets containing a 5-g dose of
product, to consume three doses per day (of 5 g
each one), before regular meals. There was an
excellent tolerance to Psyllium, without
significant adverse effects. No significant
changes were observed in the patient's weight for
both groups (not significant). Fasting plasma
glucose, total cholesterol , LDL cholesterol , and
triglycerides levels, showed a significant
reduction (p < 0.05), whereas HDL cholesterol
increased significantly (p < 0.01) following
Psyllium treatment. Our results show that 5 g
t.i.d. of Psyllium is useful, as an adjunct to
dietary therapy, in patients with type II
diabetes, to reduce plasma lipid and glucose
levels, resolving the compliance conflict
associated with the ingest of a great amount of
fiber in customary diet.
Impact
of neuroendocrine activation on coronary artery
disease
Swedberg K.B.
Dr. K.B. Swedberg, Department of Medicine,
Sahlgrenska Univ. Hospital/Ostra, S-41685 Goteborg
Sweden
American Journal of Cardiology (United States),
1998, 82/6 A (8H-14H)
Several independent predictors of the risk of
atherosclerosis are known including plasma
cholesterol concentration, cigarette smoking,
elevated blood pressure, as well as genetic
factors such as non-insulin-dependent diabetes and
plasma fibrinogen. Also known are the 3 major
elements of the pathogenesis of atherosclerosis,
involving modification of endothelial function,
changes in vascular tone, and clinical sequelae of
hyperplasia of smooth muscle cells in the intima
of the affected blood vessels. This article
further examines vasoconstrictor/vasodilator
balance, the role of angiotensin II, and the
significant role played by the endothelium in the
complex events and interactions that occur both
with smooth muscle cells and platelets. Clinical
evidence of endothelial dysfunction in coronary
artery disease is presented. The importance of the
association of the progression of coronary artery
disease with signs of neuroendocrine activation,
the relation of endothelin-1 to mechanisms of
neuroendocrine activation, and how the
counteraction of this activation may have
beneficial effects on disease progression are
discussed.
Fruit
and vegetable intake in young
children
Dennison B.A.; Rockwell H.L.; Baker S.L.
Dr. B.A. Dennison, Mary Imogene Bassett Research
Inst., One Atwell Road, Cooperstown, NY 13326-1394
United States
Journal of the American College of Nutrition
(United States), 1998, 17/4 (371-378)
Background: Current recommendations call for
most Americans, 2 years of age and over, to eat
more fruits and vegetables.
Objective: To determine, in a sample of healthy
children, the extent to which young children's
diets include the recommended numbers of fruit and
vegetable servings per day.
Design: Cross-sectional study?
Setting: A general primary care health center
in upstate New York.
Participants: One-hundred-sixteen 2-year-old
children and 107 5-year-old children, who were
scheduled for a non-acute visit, and their
parent/primary caretaker (PPC) were recruited
between 1992 and 1993.
Measurements: For 168 children (94 2-year-old
children and 74 5-year-old children), mean dietary
intakes were calculated from 7 days of written
dietary records, entered and analyzed using the
Minnesota Nutrition Data System. The numbers of
fruit and vegetable servings/day were calculated
according to USDA definitions of serving
sizes.
Results: The 2-year-old children consumed the
same amounts of fruits, 100% fruit juice, and
total fruits and vegetables as the 5-year-old
children (0.8 and 0.7 fruit servings/day, 1.0 and
0.8 juice servings/day, and 2.2 and 2.1 total
fruit and vegetable servings/day, respectively).
Fruit juice accounted for 54% of all fruit
servings consumed and 42% of all fruit and
vegetable servings consumed. Total fruit
consumption (fruits plus juice) was correlated
with carbohydrate intake (R=0.46), and inversely
correlated with total fat and saturated fat
intakes (R= -0.48 and R= -0.36, respectively, both
p<0.0001) and with cholesterol intake (R=
-0.21, p<0.01). Citrus fruit and juice
consumption was strongly correlated with vitamin C
intake (R=0.56, p<0.0001). Total vegetable
consumption was strongly correlated with
beta-carotene and vitamin A intakes (R=0.63 and
R=0.32, respectively, both p<0.0001). Total
fruit and vegetable consumption correlated with
intakes of beta-carotene, vitamin A, vitamin C,
fiber , and potassium (R=0.55, R=0.31, R=0.56,
R=0.58, and R=0.66, respectively, all
p<0.0001). Forty percent of 2-year old children
and 50% of 5-year-old children consumed <2
servings/day of fruits and vegetables. Ninety-five
percent of children consuming less than or equal
to2 servings/day of fruits and vegetables met the
RDA for vitamin C vs. 50% of those consuming <2
servings/day (p<0.001).
Conclusions: In this study, preschool-aged
children consumed, on average, about 80% of the
recommended fruit servings/day, but only 25% of
the recommended vegetable servings/day. Low
intakes of fruits and vegetables were associated
with inadequate intakes of vitamin A, vitamin C,
and dietary fiber , in addition to high intakes of
total fat and saturated fat.
Whole
flaxseed consumption lowers serum LDL- cholesterol
and lipoprotein(a) concentrations in
postmenopausal women
Arjmandi B.H.; Khan D.A.; Juma S.; Drum M.L.;
Venkatesh S.; Sohn E.; Wei L.; Derman R.
Dr. B.H. Arjmandi, Department of Nutritional
Sciences, 425 Human Environmental Sciences,
Oklahoma State University, Stillwater, OK
74078-6141 United States
Nutrition Research (United States), 1998, 18/7
(1203-1214)
We conducted a double-blind cross-over study to
compare the effects of whole flaxseed and
sunflower seed, as part of the daily diet, on the
lipid profile of postmenopausal women. During two
6-wk periods, thirty-eight mild, moderate, or
severely (5.85-9.05 mmol/L) hypercholesterolemic
postmenopausal women were randomly assigned to one
of the two regimens: flaxseed or sunflower seed.
The subjects were provided with 38 g of either
treatment in the forms of breads and muffins. The
first treatment period lasted six weeks and was
followed by a two-wk washout phase. After the
washout phase, subjects switched regimens and
treatments continued for another 6 weeks. Blood
samples were collected at baseline, 6, 8, and 14th
wk of the study periods. Significant (p<0.01)
reductions in total cholesterol were observed for
both treatments (6.9 and 5.5% for flaxseed and
sunflower seed, respectively). However only
flaxseed regimen was able to significantly
(p<0.001) lower LDL- cholesterol (14.7%). Serum
HDL- cholesterol and triglyceride concentrations
were unaffected by either of the treatments. Most
interestingly, lipoprotein(a) [Lp(a) ], a strong
predictor of cardiovascular disease,
concentrations were significantly (p<0.05)
lowered by the flaxseed treatment (7.4% compared
to baseline values). Regression analyses showed
the strongest association between age and both
total and LDL- cholesterol concentrations. Among
the dietary variables, total and soluble fiber
intakes were negatively correlated with serum
total and LDL-cholesterol concentrations. The
cholesterol lowering effects of flaxseed and
sunflower seed may be due to the activity of
single or multiple components, including
alpha-linolenic or linoleic acids, total and
soluble fiber , and non-protein constituents
present in these seeds.
The
potential role of soluble fibre in the treatment
of hypercholesterolaemia
Coats A.J.S.
A.J.S. Coats, Department of Cardiology, Royal
Brompton Hospital, London SW3 6NP United
Kingdom
Postgraduate Medical Journal (United Kingdom),
1998, 74/873 (391-394)
The three major modifiable coronary risk
factors are smoking, hypertension, and
hypercolesterolaemia. Serum cholesterol levels are
above the desirable level of 5.2 mmol/l in 79% of
men and 65% of women aged between 35 and 50 years
and thus are an important target for intervention.
In this paper, the role of nonpharmacological
intervention with soluble fibre in treating mild
to moderate primary hypercholesterolaemia is
reviewed. Evidence from controlled studies shows
that soluble fibre can be effective in lowering
cholesterol by clinically significant amounts. It
is stressed, however, that risk factors for
coronary heart disease are interactive and
attention is shifting to addressing multiple
rather that individual factors.
Nutrition and coronary heart
disease
Pandya D.P.
Dr. D.P. Pandya, 16 Lilian St., Edison, NJ 08817
United States
Comprehensive Therapy (United States), 1998, 24/4
(198-204)
Modification of the nutritional risk factors,
along with moderate amount of fiber content in
food, fresh fruits and vegetables, necessary
mineral supplements, smoking reduction and routine
physical exercise, is an important strategy for
the prevention and reduction of adverse outcome in
coronary heart disease.
Distribution and synthesis of
apolipoprotein J in the atherosclerotic
aorta
Ishikawa Y.; Akasaka Y.; Ishii T.; Komiyama K.;
Masuda S.; Asuwa N.; Choi- Miura N.-H.; Tomita
M.
Dr. Y. Ishikawa, Department of Pathology, Toho
University School of Medicine, 5-21-16
Omori-nishi, Ota-ku, Tokyo 143-8450 Japan
Arteriosclerosis, Thrombosis, and Vascular
Biology (United States), 1998, 18/4 (665-672)
The distribution of apolipoprotein (apo) J
during the development of atherosclerosis in the
human aorta was evaluated by immununohistochemical
observation, together with the other
apolipoprotein A-I, A-II, B, C-III, and E.
Although apoJ was never observed in the normal
aorta (ie, without any intimal lesions or intimal
thickening), it was distributed not only in the
intima but also in the media of aortas with
diffuse, intimal thickening or atherosclerotic
lesions. Double immunostaining with antibodies for
apoJ and alpha-smooth muscle actin revealed apoJ
deposition in smooth muscle cells (SMCs) or the
aortic stroma in the vicinity of SMCs. The extent
of apoJ distribution in the aortic wall increased
with the degree of atherosclerosis development. In
addition, the distribution pattern of apoJ was
very similar to that of apoA-I and E. In situ
hybridization with human apoJ cDNA demonstrated
intense signals in cells scattered within the
subendothelial space and medial SMCs of the aorta
with advanced atherosclerosis but not in those of
the normal aorta without intimal thickening.
Furthermore, reverse transcriptase-polymerase
chain reaction of the cultured human aortic SMCs
revealed apoJ mRNA expression in these cells. The
results indicate that apoJ in the aortic wall
originates from not only apoJ circulated in the
plasma but also apoJ produced by SMCs in the
aortic wall. Considering the similarities of the
distribution between apoJ and apo-A-I or E, we
hypothesize that apoJ possibly has a protective
role against human atherosclerosis by its
involvement with cholesterol transport from the
aortic wall to the liver.
Dietary
fiber , the evolution of the human diet and
coronary heart disease
Jenkins D.J.A.; Kendall C.W.C.; Ransom
T.P.P.
Dr. D.J.A. Jenkins, Clinical Nutrition, St.
Michael's Hospital/Dept. of Med., University of
Toronto, Toronto, Ont. M5S 3E2 United Kingdom
Nutrition Research (United States), 1998, 18/4
(633-652)
Speculation on the evolution of the human diet
together with comparative studies with the diet of
other primates suggest that the human
gastrointestinal tract and metabolism are adapted
to high fiber diets. Epidemiological studies
support a negative association between dietary
fiber intake and risk of coronary heart diseases
(CHD). For the most part, the association has been
with insoluble fiber , especially wheat bran.
However, viscous fiber sources are likely to play
a role since they reduce lipid rink factors for
CHD including total and low-density-lipoprotein
cholesterol and apolipoprotein B by increasing
fecal bile acid losses. In addition, soluble fiber
may reduce the rate of nutrient absorption so
altering chylomicron synthesis and reducing
postprandial glucose and insulin levels and other
risk factors for CHD. There is also evidence that
soma insoluble fibers might alter serum lipids and
improve carbohydrate tolerance but these phenomena
need to be confirmed and other mechanisms explored
including improved clothing and thrombolytic
factors and increased antioxidant status.
Epidemiology, clinical and laboratory studies
support increased consumption of high fiber foods
as part of the strategy to reduce the risk of
CHD.
Managing hypercholesterolaemia: What
role for dietary fibre?
Poulter N.R.
Prof. N.R. Poulter, Cardiovascular Studies Unit,
Dept. of Clin. Pharmacol./Therapeut., Imperial
College School of Medicine, St Mary's, London W2
1PG United Kingdom
British Journal of Cardiology (United Kingdom),
1998, 5/3 (156-163)
Although there is now general agreement that
lowering blood cholesterol levels brings about a
reduction in the incidence of coronary heart
disease (CHD), there is no consensus as to how and
on whom lipid lowering should be attempted. With
millions of people likely to benefit from
cholesterol lowering, many of them with no overt
signs or symptoms of CHD, managing
hypercholesterolaemia needs to be effective,
inexpensive, and highly acceptable to patients.
This review looks briefly at the need to manage
hypercholesterolaemia, and then considers the
methods available for management. In particular,
it explores the potential role of the addition of
soluble fibre to the diet.
Human
fatty acid synthesis is reduced after the
substitution of dietary starch for
sugar
Hudgins L.C.; Seidman C.E.; Diakun J.; Hirsch
J.
L.C. Hudgins, Lab. of Human Behavior and
Metabol., Rockefeller University, 1230 York
Avenue, New York, NY 10021 United States
American Journal of Clinical Nutrition (United
States), 1998, 67/4 (631-639)
Using new nonisotopic and isotopic methods, we
showed previously that fatty acid synthesis was
markedly stimulated in weight-stable normal
volunteers by a very-low-fat formula diet with 10%
of energy as fat and 75% as short glucose
polymers. In this study, we determined whether
fatty acid synthesis was equally stimulated by a
very-low-fat solid diet made with foods consumed
typically. Four normal volunteers consumed the
same very-low-fat formula diet for 25 d and then
an isoenergetic solid food diet with 10% of energy
as fat and 75% as starch, simple sugars, and fiber
for 25 d. To measure fatty acid synthesis, the
fatty acid compositions of the diets were matched
to the composition of each subject's adipose
tissue and compared with the composition of
VLDL-triacylglycerol. In all subjects, the large
increases in newly formed palmitate and decreases
in linoleate in VLDL-triacylglycerol were quickly
reversed by the solid food diet, and the fraction
of de novo synthesized fatty acids in fasting
VLDL-triacylglycerol decreased from 30- 54% to
0-1%. In a second group of subjects, the
stimulation of fatty acid synthesis by the formula
diet with 75% glucose polymers was similarly
reduced by a formula diet with amounts of fat,
starch, and sugar chosen to mimic those of the
solid food diet, but persisted after the addition
of fiber or a diet with 75% sugar. In conclusion,
an increase in fatty acid synthesis and
palmitate-rich, linoleate-poor
VLDL-triacylglycerol induced by very-low-fat,
high-sugar diets may be reduced by the
substitution of dietary starch for sugar with
potentially beneficial effects on cardiovascular
health.
LDL
oxidation: therapeutic perspectives.
Heller FR; Descamps O; Hondekijn JC
Department of Internal Medicine, Hopital de
Jolimont, Belgium.
Atherosclerosis (Ireland) Apr 1998, 137 Suppl
pS25-31
The peroxidation step of lipid transormation is
considered to be essential in the pathogenesis of
atherosclerosis. Although data concerning the
mechanisms by which lipid peroxidation occurs in
vivo are scarce, several lines of evidence suggest
that some endogenous and exogenous compounds with
antioxidant activity could have some beneficial
effects in the prevention of atherosclerosis.
Ascorbic acid (vitamin C) and alpha-tocopherol
(vitamin E) act as the most important hydrophilic
and lipophilic antioxidants, respectively in vivo.
Accordingly, animal and human studies suggest that
these compounds may have some preventive effect
against the development of clinical coronary heart
disease. Many plant phenols and flavonoids may be
important dietary antioxidants and it has been
speculated that these compounds in red wine or in
the Mediterranean diet could explain the 'French
paradox'. Several studies show that antioxidants
such as probucol and butylated hydroxytoluene can
inhibit development of atherosclerotic lesions in
Watanabe and cholesterol -fed rabbits. Some drugs
such as beta-blockers, calcium antagonists,
hypolipodemic drugs,...appear to have at least in
vitro antioxidant effects but the clinical
relevance of these properties remains unkonwn.
Moreover, some interventions aimed to decrease the
LDL-oxidative susceptibility have not been shown
to attenuate atherogenesis when cholesterol levels
remain markedly elevated. (55 Refs.)
Influence of vitamin C status on
ethanol metabolism in guinea-pigs.
Ginter E; Zloch Z; Ondreicka R
Institute of Preventive and Clinical Medicine,
Bratislava, Slovak Republic.
Physiol Res (Czech Republic) 1998, 47 (2)
p137-41
Guinea-pigs were maintained for 5 weeks on a
diet containing three different concentrations of
vitamin C : a) traces (none added), b) medium
(0.05% w/w) and high (0.5% w/w). Twenty-four hours
before killing the animals received one i.p. dose
of 3 g ethanol per kg body weight (a model of
short-term acute intoxication). In a parallel
experiment which lasted 5 weeks, the animals were
treated every week with two i.p. doses of 1 g
ethanol per kg body weight followed by the final
acute intoxication (3g ethanol/kg) (a model of
long-term chronic alcoholization). In both
experiments, the guinea-pigs with the highest
tissue concentration of vitamin C proved to have
significantly decreased residual levels of ethanol
and acetaldehyde in the liver and the brain, a
decreased activity of alanine- and aspartate
aminoacyl transferases in the serum and decreased
contents of triacylglycerols and cholesterol in
the serum and liver in comparison with the vitamin
C -unsupplemented group. The regression curve
expressing vitamin C levels versus residual
ethanol and acetaldehyde concentrations in the
liver confirmed the highly significant negative
correlation between them. Administration of the
guinea-pigs with large amounts of vitamin C
appears to accelerate ethanol and acetaldehyde
metabolism and reduce some of their adverse health
effects.
Dietary
antioxidants inhibit development of fatty streak
lesions in the LDL receptor-deficient
mouse.
Crawford RS; Kirk EA; Rosenfeld ME; LeBoeuf RC;
Chait A
Department of Medicine, University of Washington,
Seattle 98195-6426, USA.
Arterioscler Thromb Vasc Biol (United States) Sep
1998, 18 (9) p1506-13
Oxidized low density lipoprotein (LDL) promotes
atherogenesis. Although pharmacological
antioxidants such as probucol inhibit both LDL
oxidation and atherosclerosis in hyperlipidemic
animals, the effects of natural antioxidants such
as vitamin E are inconclusive. To further
determine the effects of supplemental dietary
antioxidants in vivo, we evaluated whether
combined dietary antioxidants (0.1% vitamin E,
0.5% beta-carotene, and 0.05% vitamin C) inhibit
LDL oxidation and fatty streak lesion development
in homozygous LDL receptor-null (LDLR-/-) mice fed
a high-fat, high- cholesterol diet. An additional
group of mice were fed black tea, which has been
shown to inhibit LDL oxidation in vitro. After
receiving a high-fat, high- cholesterol diet for 8
weeks, the combined antioxidant-supplemented
(antioxidant) group (n=18), tea group (n=19), and
control group (n=17) had equivalent plasma
cholesterol levels. LDL oxidation, as measured by
the lag phase of conjugated diene formation, was
markedly inhibited in the antioxidant group
compared with the tea or control groups [mean lag
phases=143+/-7 (antioxidant), 100+/-5 (tea), and
84+/-4 (control) minutes; P<0.0001 antioxidant
versus tea or control]. The cross-sectional
surface area of fatty streak lesions in the aortic
sinus was reduced by 60% in the antioxidant group
compared with both the tea and control groups
(P<0.0001 antioxidant versus tea or control).
There was no difference in lesion area between tea
and control groups. Although both LDL oxidation
and atherosclerosis were significantly inhibited
in the antioxidant group, no correlation between
lag phase values and lesion size was observed
among individual animals. Furthermore, black tea
did not inhibit fatty streak development in
LDLR-/- mice. These data suggest that combined
natural dietary antioxidants inhibit both LDL
oxidation and atherogenesis in animals with
elevated LDL but that inhibition of LDL oxidation
alone may not prevent the development of
atherosclerosis.
Vitamin
E combined with selenium inhibits atherosclerosis
in hypercholesterolemic rabbits independently of
effects on plasma cholesterol
concentrations.
Schwenke DC; Behr SR
Department of Pathology, Wake Forest University
School of Medicine, Winston-Salem, NC 27157-1072,
USA.
schwenke@bgsm.edu
Circ Res (United States) Aug 24 1998, 83 (4)
p366-77
Several antioxidants inhibit atherosclerosis.
This study investigated the hypothesis that
combining vitamin E, a lipophilic antioxidant,
with vitamin C , a hydrophilic antioxidant, and/or
selenium, a cofactor of peroxidases that detoxify
lipid peroxides, would inhibit atherosclerosis
more effectively than vitamin E alone. We also
considered whether regional variation in
inhibition of atherosclerosis by antioxidants
would be associated with regional variation in
aortic lipophilic antioxidants. Rabbits were fed
an atherogenic diet (control) or an atherogenic
diet supplemented with vitamin E, vitamins E and
C, vitamin E+selenium, vitamins E and C+selenium,
or probucol (positive control). Supplements were
as follows: vitamin E, 146 IU/d; vitamin C , 791
mg/d; selenium, 22 microg/d; or probucol, 406
mg/d. Vitamin C did not influence atherosclerosis.
After 22 weeks of treatment, rank order of aortic
atherosclerosis was control>vitamin E (with or
without vitamin C )>vitamin E+selenium (with or
without vitamin C)>probucol. Antioxidant
treatment reduced aortic cholesterol
concentrations 21% to 56%, 29% to 86%, and 19% to
75% for the aortic arch, descending thoracic
aorta, and abdominal aorta, respectively
(P<0.025 to P<0.0003 by ANOVA), with
slightly greatly reductions for areas of
atherosclerotic lesions. Some treatments reduced
plasma cholesterol concentrations, but none
altered the distribution of cholesterol among
lipoproteins. Corrected for differences in plasma
cholesterol concentrations, aortic cholesterol
concentrations were reduced up to 72% (P<0.02)
by the antioxidant treatments, with equal
reductions by vitamin E+selenium and by probucol.
Aortic alpha-tocopherol standardized by aortic
cholesterol as a measure of aortic lipids was
lower in the abdominal aorta than in the aortic
arch of rabbits not given alpha-tocopherol and
increased relatively more in the abdominal aorta
than in the aortic arch with alpha-tocopherol
supplementation. The results of this study suggest
that vitamin E+ selenium inhibited atherosclerosis
as effectively as an equally hypocholesterolemic
dose of probucol by a mechanism(s) that is in part
independent of effects on plasma and lipoprotein
cholesterol concentrations. The tendency for
greater efficacy of antioxidant treatments in the
abdominal aorta than aortic arch may relate to the
lower concentrations of alpha-tocopherol in the
abdominal aorta of unsupplemented rabbits.
Regulation of apolipoprotein
B-containing lipoproteins by vitamin C level and
dietary fat saturation in guinea
pigs.
Montano CE; Fernandez ML; McNamara DJ
Department of Nutritional Sciences and
Interdisciplinary Nutritional Science Program,
University of Arizona, Tucson, USA.
Metabolism (United States) Jul 1998, 47 (7)
p883-91
Effects of suboptimal and adequate vitamin C ,
with varying dietary fat saturation, on hepatic
cholesterol and plasma lipoprotein concentrations
and metabolism were studied in guinea pigs fed 15%
(wt/wt) fat/0.04% cholesterol diets. Fat mixtures
were either 49% saturated (SFA) (24% lauric acid)
or 53% polyunsaturated fatty acid (PUFA) linoleic
acid with vitamin C at 50 (suboptimal) or 500
(adequate) mg/kg diet. Guinea pigs fed suboptimal
vitamin C had 15% lower hepatic active
3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA)
reductase activity and 25% lower low-density
lipoprotein (LDL; apolipoprotein [apo] B/E)
receptor number, 20% higher acyl-CoA:cholesterol
acyltransferase (ACAT) activity, 28% higher
triacylglycerol (TAG) and cholesteryl ester
concentrations, and increased very-low-density
lipopoprotein (VLDL) apo B secretion rates in
comparison to animals fed adequate vitamin C.
Intake of suboptimal vitamin C lowered plasma
high-density lipoprotein (HDL) cholesterol
concentrations by 45% and increased plasma TAG,
total and VLDL/LDL cholesterol , and cholesteryl
ester transfer protein (CETP) activity by 40%,
50%, and 30%, respectively. The hyperlipidemic
effects of suboptimal vitamin C were more
pronounced with intake of the SFA diet. These data
demonstrate that low vitamin C intake results in a
pattern of changes in whole-body cholesterol and
lipoprotein metabolism that are related to
increased risk of cardiovascular disease
(CVD).
The
nutritional health of New Zealand vegetarian and
non-vegetarian Seventh-day Adventists: selected
vitamin, mineral and lipid levels.
Harman SK; Parnell WR
Department of Human Nutrition, University of
Otago, Dunedin.
N Z Med J (New Zealand) Mar 27 1998, 111 (1062)
p91-4
AIM: To determine whether adult non-vegetarian
Seventh-day Adventists differ in selected
nutrition related health aspects from adult
vegetarian Seventh-day Adventists.
METHODS: One hundred and forty-one Seventh-day
Adventist church members responded to a general
health questionnaire. Forty-seven sex and age
matched subjects (23 non-vegetarians and 24
vegetarians) were selected for further
investigation. Blood lipids, serum vitamin B12,
folate, haemoglobin and ferritin levels were
measured along with stature, weight and blood
pressure. A quantitative 7-day diet record was
also completed.
RESULTS: Body mass index was similar between
the non-vegetarian and vegetarian groups but
diastolic blood pressure was higher for
non-vegetarian than vegetarian males. Even though
the dietary vitamin B12 intake was significantly
lower (p < 0.01) in the vegetarian group both
vegetarians and non-vegetarians recorded similar
serum vitamin B12 levels. The vegetarian and
non-vegetarian groups had similar haemoglobin
concentrations. While dietary iron intake was
higher in the female vegetarian group, though
predominantly in the non-haem form, the difference
was not significant. Low serum ferritin levels
were found in both female dietary groups even
though the vegetarian group had a significantly (p
< 0.05) higher vitamin C intake. Blood lipid
levels were similar in the two diet groups even
though the vegetarian group had a lower percentage
energy contribution from total and saturated fat
(p < 0.01) and consumed significantly less
cholesterol.
CONCLUSION: Both non-vegetarian and vegetarian
Seventh-day Adventists appear likely to enjoy a
lower risk of nutrition related chronic
degenerative disease than the average New
Zealander and have a satisfactory iron and vitamin
B12 status.
Characteristics of survey
participants with and without a telephone:
findings from the third National Health and
Nutrition Examination Survey.
Ford ES
Division of Nutrition, Centers for Disease
Control and Prevention, Atlanta, Georgia 30341,
USA.
J Clin Epidemiol (England) Jan 1998, 51 (1)
p55-60
This study examines the potential coverage bias
in telephone surveys. Data were analyzed from the
first phase of the third National Health and
Nutrition and Examination Survey conducted from
1988 to 1991. In that survey, 10,120 persons 17
years and older were interviewed and 9034 were
examined. About 2.7% of respondents reported not
having a telephone. Differences in demographic and
lifestyle variables, but not physiological or
anthropometric variables, existed between persons
with a telephone and those without one.
Respondents without a telephone were more likely
to report that an impairment or health problems
limited their work or activities. Compared with
respondents with a telephone, those without one
were more likely to be current smokers, to be less
physically active, to never have had their blood
pressure checked or have had it checked more than
5 years ago, and to never have had their
cholesterol checked. Based on data from a 24-hour
dietary recall, persons without a telephone
consumed less vitamin A, vitamin C , vitamin E,
and carotene than did respondents with a
telephone. However, prevalence estimates of health
characteristics obtained from telephone surveys in
populations with high telephone coverage are
unlikely to be seriously affected by coverage bias
nor are con |