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Consumption of extra virgin olive oil improves body composition and blood pressure in women with excess body fat: a randomized, double-blinded, placebo-controlled clinical trial


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Purpose: Despite the fact that extra virgin olive oil (EVOO) is widely used in obese individuals to treat cardiovascular diseases, the role of EVOO on weight/fat reduction remains unclear. We investigated the effects of energy-restricted diet containing EVOO on body composition and metabolic disruptions related to obesity. Methods: This is a randomized, double-blinded, placebo-controlled clinical trial in which 41 adult women with excess body fat (mean ± SD 27.0 ± 0.9 year old, 46.8 ± 0.6% of total body fat) received daily high-fat breakfasts containing 25 mL of soybean oil (control group, n = 20) or EVOO (EVOO group, n = 21) during nine consecutive weeks. Breakfasts were part of an energy-restricted normal-fat diets (-2090 kJ, ~32%E from fat). Anthropometric and dual-energy X-ray absorptiometry were assessed, and fasting blood was collected on the first and last day of the experiment. Results: Fat loss was ~80% higher on EVOO compared to the control group (mean ± SE: -2.4 ± 0.3 kg vs. -1.3 ± 0.4 kg, P = 0.037). EVOO also reduced diastolic blood pressure when compared to control (-5.1 ± 1.6 mmHg vs. +0.3 ± 1.2 mmHg, P = 0.011). Within-group differences (P < 0.050) were observed for HDL-c (-2.9 ± 1.2 mmol/L) and IL-10 (+0.9 ± 0.1 pg/mL) in control group, and for serum creatinine (+0.04 ± 0.01 µmol/L) and alkaline phosphatase (-3.3 ± 1.8 IU/L) in the EVOO group. There was also a trend for IL-1β EVOO reduction (-0.3 ± 0.1 pg/mL, P = 0.060). Conclusion: EVOO consumption reduced body fat and improved blood pressure. Our results indicate that EVOO should be included into energy-restricted programs for obesity treatment.
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Eur J Nutr (2018) 57:2445–2455
Consumption ofextra virgin olive oil improves body composition
andblood pressure inwomen withexcess body fat: arandomized,
double‑blinded, placebo‑controlled clinical trial
FláviaGalvãoCândido1 · FláviaXavierValente1· LaísEmiliadaSilva1·
OlíviaGonçalvesLeãoCoelho1· Maria do CarmoGouveiaPeluzio1·
Rita de CássiaGonçalvesAlfenas1
Received: 10 March 2017 / Accepted: 23 July 2017 / Published online: 14 August 2017
© Springer-Verlag GmbH Germany 2017
serum creatinine (+0.04±0.01µmol/L) and alkaline phos-
phatase (−3.3±1.8IU/L) in the EVOO group. There was
also a trend for IL-1β EVOO reduction (−0.3±0.1pg/mL,
Conclusion EVOO consumption reduced body fat and
improved blood pressure. Our results indicate that EVOO
should be included into energy-restricted programs for obe-
sity treatment.
Keywords Extra virgin olive oil· Soybean oil· Body fat·
Blood pressure· Adiposity· Monounsaturated fatty acid
Obesity results from complex interactions between genetic
and lifestyle factors. The consumption of high-fat diets has
been considered one of the main factors predisposing fat
gain [13]. However, the role of dietary fat on obesity patho-
genesis remains unclear.
Extra virgin olive oil (EVOO) is a high-quality oil rich in
monounsaturated oleic acid (55–85% of fatty acid content),
which contains more than 230 chemical constituents with
antioxidant activity such as vitamin E, carotenoids, and phe-
nolic compounds [4]. Due to the well-established beneficial
effects of that oil over CVD risk [58] and the strong associ-
ation between CVD and excess body fat, the consumption of
energy-restricted diet containing EVOO has been adopted in
weight loss programs. However, the benefits of EVOO over
CVD have been inadvertently extrapolated for weight/fat
loss promotion without adequate scientific evidence [9, 10].
The current hypothesis that EVOO could also contribute
to weight/fat loss is mostly based on observational evidence,
demonstrating that the consumption of Mediterranean diet
rich in olive oil was significantly less likely to favor obesity
Purpose Despite the fact that extra virgin olive oil (EVOO)
is widely used in obese individuals to treat cardiovascular
diseases, the role of EVOO on weight/fat reduction remains
unclear. We investigated the effects of energy-restricted diet
containing EVOO on body composition and metabolic dis-
ruptions related to obesity.
Methods This is a randomized, double-blinded, placebo-
controlled clinical trial in which 41 adult women with excess
body fat (mean±SD 27.0±0.9 year old, 46.8±0.6% of
total body fat) received daily high-fat breakfasts containing
25mL of soybean oil (control group, n=20) or EVOO
(EVOO group, n=21) during nine consecutive weeks.
Breakfasts were part of an energy-restricted normal-fat
diets (−2090kJ,~32%E from fat). Anthropometric and
dual-energy X-ray absorptiometry were assessed, and
fasting blood was collected on the first and last day of the
Results Fat loss was~80% higher on EVOO com-
pared to the control group (mean±SE: −2.4±0.3 kg vs.
−1.3±0.4kg, P=0.037). EVOO also reduced diastolic
blood pressure when compared to control (–5.1±1.6mmHg
vs. +0.3±1.2mmHg, P=0.011). Within-group differences
(P<0.050) were observed for HDL-c (−2.9±1.2mmol/L)
and IL-10 (+0.9±0.1pg/mL) in control group, and for
Electronic supplementary material The online version
of this article (doi:10.1007/s00394-017-1517-9) contains
supplementary material, which is available to authorized users.
* Flávia Galvão Cândido
1 Departamento de Nutrição e Saúde, Universidade
Federal de Viçosa, Avenida PH Rolfs, s/n, Viçosa,
MinasGeraisCEP:36570-900, Brazil
2446 Eur J Nutr (2018) 57:2445–2455
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[1113]. Results from these observational studies are dif-
ficult to interpret because habitual use of olive oil in salads
and vegetable-based dishes within the Mediterranean diet
is also associated with the consumption of other functional
low-density foods [10, 14]. Furthermore, randomized clini-
cal trials about this topic are scarce, and presented inconclu-
sive and controversial results [10, 15]. In some clinical trials,
the great discrepancy in the dietary intervention applied to
the control and test groups may have favored the reduction
in body weight/fat in response to olive oil consumption [16,
17]. On the other hand, other clinical trials reported no influ-
ence of olive oil on body weight/fat [18] or even an increase
in abdominal obesity [19] when it was incorporated into
Mediterranean diet. When consumed associated with an
energy-restricted non-Mediterranean diet, olive oil reduced
less body weight than medium-chain triacylglycerol—MCT
Despite the fact that the incorporation of good fat source
into energy-restricted diets can improve palatability and
favor compliance of the traditional energy-restricted low-
fat diet [21], there is no clear evidence supporting the effect
of EVOO to improve body weight/fat loss. Therefore, we
investigated the effect of the consumption of EVOO into an
energy-restricted non-Mediterranean diet on body weight/
fat. Additionally, we assessed the role of EVOO on systemic
inflammation, cardiovascular, hepatic and renal functions,
which can be impaired due to lipotoxicity.
Seven hundred fifty-three women were assessed for eli-
gibility through local advertisements and seventy-seven
apparently healthy middle-aged women (19–41 years, BMI
between 26 and 35kg/m2) met the inclusion criteria and
were allocated to study groups (Fig.1). Potential subjects
had excess body fat (>32%); habitually used soybean oil
as cooking oil; were nonsmoker, non-pregnant, and non-
lactating. The exclusion criteria were the followings: alcohol
consumption (>15g of ethanol/day), elite athletes (>10h of
exercise/week), habitual consumption of olive oil (more than
8mL/day), recent changes (<3 months) in diet or physical
activities habits, use of supplements or drugs except con-
traceptive ones, the presence of food allergy/intolerance or
aversion to tested ingredients, gastrointestinal diseases or
other acute or chronic diseases besides obesity.
From the 77 initially recruited women, 16 dropped out
before starting the intervention. Sixty-one eligible women
were included in the study, 51 completed the adopted pro-
tocol, and 41 were included in the analyses. The reasons by
which ten women were not included in the final analyses
were the following: pregnancy (n=1), secondary pathologi-
cal events not related to the intervention (n=6) and drop
out (n=3). Because all subjects which finished the study
follow the entire study protocol, there was no exclusion due
to lack of compliance in this study. Power calculation was
performed retrospectively [22] and indicated that 21 sub-
jects were necessary to detect an increment of 1.09kg in
total body fat loss presented by EVOO group (mean±stand-
ard deviation of change in body fat loss of overall subjects;
1.9±1.8kg; statistical power=90%; α=5%). An incre-
ment of~1kg in body fat loss is relevant considering the
duration of this study and this preventive nature [23].
All recruited participants gave written consent after
receiving verbal and written information about the experi-
ment. The study protocol was approved by the Ethics Com-
mittee of Universidade Federal de Viçosa (protocol number:
892.467/2014), conducted in accordance with 1964 Declara-
tion of Helsinki and its latter amendments, and registered at (identifier: RBR-7z358j).
Experimental design
This was a double-blinded, randomized, parallel, pla-
cebo-controlled clinical trial for nine consecutive weeks
(±5days), in which subjects were randomly assigned to
control (soybean oil) or interventional (EVOO) groups. The
tolerance of±5days to end the experiment was required
to prevent impairment on anthropometric/body composi-
tion parameters assessments due to hormonal changes. The
allocation on the control or interventional groups was made
using the block randomization technique [24] and was con-
cealed from the investigators. High-fat drinks were served
into colored cups to avoid visual identification of the type
of drink tested. There was no description or dietary infor-
mation about the breakfasts on those cups. Therefore, nei-
ther subjects nor investigators were aware of the treatment
One week before beginning the trial, selected women
refrained from eating olive oil, were instructed to not con-
sume alcohol beverages and to maintain their usual dietary
and physical activity habits. A standard dinner (2508kJ, car-
bohydrate: 62 E%, fat: 29.4 E%, protein: 8.5 E%) was con-
sumed the night before the test day. Women were reported to
laboratory in a fasting state for anthropometric, body com-
position, and blood pressure assessments at baseline and on
the last day of the experiment. Inclusion in the study was
postponed if women presented any symptoms of inflamma-
tion or intestinal disorder. After the assessments, subjects
underwent blood collection and consumed a high-fat break-
fast containing 25mL of soybean oil or EVOO for breakfast.
The amount of oil (25mL) added to the drinks was based
on the range of olive oil usually consumed by Mediterra-
nean population (25–50mL/day) [25] without exceeding the
2447Eur J Nutr (2018) 57:2445–2455
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fat consumption recommendations [26]. During the other
study days, high-fat breakfasts were daily provided in the
laboratory as part of an energy-restricted non-Mediterranean
diet and women were released from the laboratory to follow
the prescribed diet in free-living conditions. Habitual food
intake, physical activity level, and prescribed diet compli-
ance were also assessed (Suppl. Figure1).
Extra virgin olive oil (Andorinha®, Sovena S.A., Algés, Por-
tugal) and soybean oil (Corcovado, Archer Daniels Mid-
land, Uberlândia, Brazil) were used to prepare the high-fat
drinks (300mL of a milk-derived flavored drink contain-
ing 25mL of the previously mentioned oils) as part of a
breakfast. Both oils were protected from light and heat until
their consumption. The high-fat drinks were matched in all
ingredients except for the type of oil used to prepare them.
During all the experimental period, subjects attended the
laboratory daily on weekdays to have the breakfasts accord-
ing to the allocated group. On weekends, identical breakfasts
containing the test oils were provided to be consumed at
home. Besides the high-fat drinks, two low-fat cookies were
also offered for breakfast. A rotating menu of six break-
fast flavors, with very similar nutritional composition, was
prepared to avoid monotony and to improve compliance to
the study protocol (Suppl. Table1). Protocol compliance on
weekends was assessed by asking subjects about the break-
fast consumption and by the return of the packages in which
the breakfasts were taken. Subjects were not informed about
the exclusion of the study if they did not follow the protocol
to guarantee the confidence of the information.
Fig. 1 CONSORT diagram
showing the flow of participants
through each stage of the trial.
CONSORT Consolidated Stand-
ards of Reporting Trials
Allocated to olive oil intervention (n= 38)
Received allocated intervention (n=33)
Did not receive allocated intervention (n= 5)
Lost to follow-up(n=0)
Discontinued intervention (n=7)
-Secondary pathological events (n= 3)
-Drop out due to personal reasons (n= 3)
Allocated to control intervention (n= 39)
Received allocated intervention (n=28)
Did not receive allocated intervention (n= 11)
Excluded (n= 675)
Not meeting inclusion criteria (n= 519)
Declined to participate (n= 122)
Other reasons (n= 34)
Analyzed (n= 21)
Did not include from analysis
-Pregnancy(n= 1)
-Secondary pathological events (n= 2)
-Drop out due to personal reasons (n = 2)
Analyzed (n= 20)
Did not include from analysis
-Secondary pathological events (n=4)
-Drop out due to personal reasons (n=1)
Enrollment Assessed for eligibility (n= 752)
Lost to follow-up (n= 0)
Discontinued intervention
-Secondary pathological events (n= 3)
Allocation Randomized (n= 77)
2448 Eur J Nutr (2018) 57:2445–2455
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EVOO and soybean oil fatty acids profile were performed
in triplicate. Fatty acid composition of EVOO was assessed
in laboratory after esterification [27] by gas chromatography
(GC) [28] (Suppl. Table1).
Dietary assessments
Energy-restricted nutritionally balanced diets were individu-
ally prescribed by a single dietitian. The type of foods pre-
scribed and the macronutrient distribution were maintained
during the intervention to reduce the influence of prescribed
diets beyond fats on results. There were no differences on
energy and macronutrient content of prescribed diet between
groups (7836.7±897.4kJ, carbohydrate: 49.0±2.8% E,
fat: 31.8±2.85% E, protein: 19.1±2.4% E). No other high
MUFA food besides the 25mL of EVOO for the EVOO
group was prescribed, and a food substitution list was used
to subsidize food choices.
Total energy requirements were estimated according to
total energy expenditure for overweight/obese women [26].
Then, caloric restriction (−2090kJ/day) was applied. Physi-
cal activity levels [29] were used to obtain physical activ-
ity coefficients (1.00 for sedentary or 1.16 for low-active
individuals) [26]. Three non-consecutive days (2 weekdays
and 1 weekend day) 24-h food records were applied to
assess food intake on the week before baseline, and during
the experimental period. Macro- and micronutrient intakes
were analyzed by a single dietitian using DietPro software
(version 5.2i, Agromídia, MG, Brazil), and were based on
reliable composition tables [3032].
Anthropometric, body composition, andblood pressure
Anthropometric measurements were assessed by a single
investigator. Body weight was measured on a digital platform
scale with a resolution of 0.5kg (Toledo®, Model 2096PP/2,
SP, Brazil), while subjects were barefoot and wearing light-
weight clothing. Height was measured to the nearest 0.1cm
using a wall-mounted stadiometer (Wiso, Chapecó, SC, Bra-
zil). BMI was calculated by dividing body (kg) by height
(m) squared. Waist, hip, neck, and thigh circumferences, as
well as sagittal abdominal diameter, were measured in trip-
licate as described by Vasques etal. [33]. The average of
the two nearest values of the three collected measurements
was recorded. Waist circumference and sagittal abdominal
diameter were measured in the midpoint between the last
rib and iliac crest. Waist/hip, and conicity index (CI) were
calculated following the formula: CI=[waist circumference
(m)]/[0.109 √(body weight (kg)/height (m))] [34]. Blood
pressure was measured by an automatic Omron HEM-7200
device (Omron Inc., Dalian, China) in both arms, according
to Mancia etal. [35].
Dual-energy X-ray absorptiometry scan (DXA) (model
Prodigy Advance, GE Healthcare Inc., Waukesha, WI) was
performed to assess changes in body composition according
to manufacturer’s instructions. Values of lean mass, total
body fat, and fat distribution (truncal, gynoid, and android
regions) were obtained.
Metabolic biomarkers
Antecubital blood samples were collected in the fasting state
(12h). Serum (serum gel tubes) and plasma (EDTA tubes)
samples were separated from whole blood by centrifugation
(3500rpm, 4°C, 15min) and immediately frozen at −80°C
until analyses. Serum glucose, triglycerides (TG), total cho-
lesterol, high-density lipoprotein cholesterol (HDL-c), low-
density lipoprotein cholesterol (LDL-c), uric acid, urea,
creatinine, alkaline phosphatase (AP), γ-glutamyltransferase
(Gamma GT), aspartate amino transferase (AST), and ala-
nine amino transferase (ALT) were quantified by an auto-
mated analyzer system (BS-200™ Chemistry Analyzer,
Mindray) using available commercial colorimetric assay
kits (K802, K117, K083, K071, K088, K139, K056, K067,
K021, K080, K048, and K049, respectively; Bioclin®, MG,
Brazil). The serum very-low-density lipoprotein cholesterol
(VLDL-c) was calculated using Friedewald etal. equations
[36]. Serum insulin was quantified using eletroquimiolumi-
nescence method (Elecsys-Modular E-170, Roche Diagnos-
tics Systems). The homeostasis model assessment of insulin
resistance (HOMA-IR) was calculated to estimate insulin
resistance according to the equation proposed by Matthews
etal. [37]. atherogenic index (TG/HDL-c ratio) were also
calculated [38].
Flow cytometry analysis was performed using a BD
FACS Verse™ flow cytometer (BD Biosciences). Interleu-
kin-8 (IL-8), interleukin-1β (IL-1β), interleukin-6 (IL-6),
interleukin-10 (IL-10), tumor necrosis factor-α (TNF-α),
and interleukin-12p70 (IL-12p70) plasma concentrations
were measured using commercial kit (Cytometric Bead
Array CBA Human Inflammatory Cytokines Kit, BD Bio-
sciences) according to the manufacturers’ instructions. Data
were analyzed using the FCAP Array Software v3.0 (BD
Statistical analysis
Data were typed by two independent investigators to ensure
data reliability. Group data were coded before the data analy-
ses for blindness. Per-protocol analyses were performed due
to the large number of participants who did not complete
the intervention after being randomized. Statistical analy-
ses were carried out on SPSS 20 for Windows (SPSS, Inc.,
Chicago, IL, USA). Data are expressed as mean±standard
deviation (SD) for descriptive variables or mean±standard
2449Eur J Nutr (2018) 57:2445–2455
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error (SE) and median (interquartile range) for comparative
data. Individual outlier values were excluded before analy-
ses. The thresholds for lower and upper outliers were defined
as follows: lower thresholds=lower quartile—(1.5 × inter-
quartile range) and upper threshold=upper quartile+(1.5
× interquartile range). Data normality and homoscedasticity
were assessed by Shapiro–Wilk and Levene’s tests, respec-
tively. Paired Student’s t test or Wilcoxon signed-rank test
were used to assess within group differences. Differences
between groups were assessed over absolute delta (Δ) values
(9weeks—baseline) by Student’s t test or Mann–Whitney U
signed-rank test. Pearson’s or Spearman’s correlation coef-
ficients were used to assess the relation between fat reduc-
tion and metabolic biomarkers. A 5% α level of significance
was adopted.
Forty-one women completed the study protocol and were
included in the analyses. Participants were 27.0±0.9
years old, presented 46.8±0.6% of total body fat, and
30.2±0.4kg/m2 of BMI (overweight: n=23 or 56.1%;
obese: n=18 or 43.9%). There were no significant between-
group differences in baseline food intake and in all anthro-
pometric, body composition, blood pressure, and metabolic
variables assessed in this study, except for diastolic blood
pressure and TNF-α which EVOO presented higher values
(Table1). None of the participants had systolic blood pres-
sure higher than 139mmHg and only one EVOO group par-
ticipant had diastolic blood pressure ranging from 90 to 99
(first state of hypertension). Despite the fact that none of
the participants showed symptoms of acute inflammation
during the test days, five of them presented a clear inflam-
matory cytokines profile (TNF-α and IL-6 values were twice
as higher as the highest values showed by the total sample)
and were excluded from final analysis. Eight participants
from both groups presented TNF-α concentration below the
detection limits of the assay kit. Six participants from the
control group and five from the EVOO group had no detect-
able concentrations for IL-1β. That did not occur for the
other cytokines.
Dietary assessments
As expected, food intake analyses during experiment period
showed reduction in energy and macronutrients intake values
compared to baseline in both groups due to energy restric-
tion. Dietary intake during the experiment only differed
between groups for C18:1, C18:2, total monounsaturated
fatty acids, and total polyunsaturated fatty acids (P<0.001),
reflecting the differences in the fatty acid profile of the sup-
plemented oils (Table2).
Anthropometric, body composition, andblood pressure
Body weight (−1.70±0.47 kg 95% CI −2.69 to −0.72
vs. −2.75±0.38 kg 95% CI −3.54 to −1.95 for con-
trol and EVOO groups, respectively; Pinter=0.094) and
BMI (−0.64±0.17kg/m2, 95% CI −1.00 to −0.28 vs.
−1.06±0.15kg/m2 95% CI −1.37 to −0.75; Pinter=0.072)
reduced with time in both groups due to energy restriction.
However, EVOO presented a greater reduction on total body
fat than control (−1.30±0.40kg 95% CI −2.21 to −0.44
vs. −2.4±0.3kg 95% CI −3.1 to −1.73, Pinter=0.037).
Fat loss was~80% higher on EVOO compared to control
group. In addition, EVOO reduced diastolic blood pres-
sure (+0.25±1.16 mmHg, 95% CI −2.18 to 2.68 vs.
−5.05±1.60mmHg 95% CI −8.39 to −1.70; Pinter=0.011).
There were no differences between groups in systolic blood
pressure (−3.65±1.54mmHg 95% CI −6.87 to −0.44 vs.
−3.91±1.88mmHg 95% CI −7.83 to 0.02; Pinter=0.918)
There was no difference between groups for the other
variables. As expected all of the evaluated anthropomet-
ric variables, except waist/thigh ratio reduced with time
in control and EVOO groups. In addition, both groups
showed weight reductions on total fat and specific fat
mass sites (truncal, gynoid, and android regions), but
not on lean mass (Suppl. Table2). Total body lean mass
Table 1 Baseline characteristics of study subjects according to
experimental groups
Values are mean±SE or median (interquartile range). Waist circum-
ference values were measured at umbilical level
BMI body mass index, S/LA number of sedentary and low-active indi-
vidual ratios (28), SAD Sagittal abdominal diameter, MUFA monoun-
saturated fatty acids, PUFA polyunsaturated fatty acids, SFA saturated
fatty acids
Control Extra virgin olive oil
Subjects (n) 20.0 21.0
Age (years) 27.2±6.1 26.8±5.0
Physical activity (S/LA) 6.00/14.0 3.00/18.0
Systolic blood pressure (mmHg) 109±2.10 115±2.40
Diastolic blood pressure (mmHg) 67.5±1.50 74.5±1.90
Body weight (kg) 77.6±2.00 77.6 (13.2)
BMI (kg/m2) 29.7±0.60 30.5±0.60
Waist circumference (cm) 97.7±1.60 98.9±1.60
SAD (cm) 19.6±0.50 19.7±0.40
Total body fat (kg) 37.0±1.40 34.4 (11.2)
Total body fat percentage (%) 46.6±0.70 47.0±0.90
Total lean mass (%) 49.4±0.84 49.0±0.98
2450 Eur J Nutr (2018) 57:2445–2455
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Table 2 Dietary assessments at baseline and change from baseline (95% CI) according to experimental groups
Values are mean±SE or median (interquartile range)
SFA saturated fatty acids, MUFA monounsaturated fatty acids, PUFA polyunsaturated fatty acids, C18:1 oleic fatty acid, C18:2 linoleic fatty
acid, PInter between-group Δ values (9week—baseline) by Student’s t test or Mann–Whitney U signed-rank test, P>0.050
Metabolic biomarkers Control (n=20) Extra virgin olive oil (n=21) PInter
Baseline Δ values 95% CI Baseline Δ values 95% CI
Energy content (kJ) 3565 (2775) −794±184 −1179 to −406 8343±434 −1041±179 − 1417 to − 665 0.342
Carbohydrate (g) 229 (66.7) −24.5±5.66 −36.4 to −12.6 261±16.1 −36.1±5.88 −48.4 to −23.7 0.165
(%E) 50.8±1.58 51.8 (55.2) 21.9 to 159 52.2±1.54 54.6 (74.5) 30.1 to 93.7 0.624
Fiber (g) 19.2±1.50 −0.60±0.72 −2.11 to 0.91 21.0±1.50 −1.67±1.09 −3.95 to 0.61 0.418
Protein (g) 78.2±5.30 −9.66±2.39 −14.7 to −4.65 81.8±3.5 −11.1±2.02 −15.3 to −6.84 0.654
(%E) 16.6±0.79 15.8 (25.2) −21.6 to 37.9 16.8±0.72 18.8 (24.1) 7.06 to 60.7 0.840
Total fat (g) 61.8 (25.6) −2.11 (12.2) −7.96 to 1.82 67.7±5.04 −2.80 (17.1) −10.7 to 0.27 0.708
(%E) 30.1±1.41 23.8 (52.4) −73.2 to 44.3 30.2±1.19 13.7 (59.4) −37.2 to 27.5 0.773
Total SFA (g) 20.1 (12.3) −2.41 (4.42) −5.86 to −1.95 21.1±1.50 −2.60 (4.72) −4.90 to −2.00 0.954
Total MUFA (g) 16.4 (9.11) −1.54±0.64 −2.89 to −1.20 20.2±1.46 4.56 (4.56) 1.53 to 6.04 <0.001
Total PUFA (g) 10.6 (5.18) 5.57 (3.96) 3.24 to 5.82 12.8 (11.2) −2.84 (4.05) −5.30 to −1.32 <0.001
C18:1 (g) 11.7±0.99 0.85±0.42 −0.03 to 1.72 13.8±1.15 6.23 (3.28) 4.00 to 7.49 <0.001
C18:2 (g) 7.49 (3.64) 5.07 (2.99) 3.57 to 5.51 9.67 (5.22) −1.73 (2.55) −3.83 to −0.65 <0.001
Cholesterol (mg) 222±17.0 −37.6±10.0 −58.7 to −16.6 251±20.8 −45.5±13.4 −73.7 to −17.3 0.642
Sodium (mg) 2469±159 −408±79.8 −575 to −240 2168 (1662) −404 (807) −908 to −385 0.234
Changes in body weight (kg)
Changes in total body fat
Changes in systolic blood
pressure (mmHg)
diastolic blood
pressure (mmHg)
P Inter= 0.094 P Inter= 0.072 P Inter= 0.037
P Inter= 0.011
P Inter= 0.918
Fig. 2 Mean ± SE body weight (a), body mass index – BMI (b),
total body fat (c), systolic blood pressure (d), and diastolic blood
pressure (e) changes (Δ values= 9 week values – baseline values).
Energy-restricted nutritionally balanced diets (−2090kJ/d) contain-
ing 25mL of soybean oil (control group, n=20) or extra virgin olive
oil – EVOO (EVOO group, n=21) were prescribed. *Within-group
significant differences (paired Student’s t test or Wilcoxon signed-
rank test, P<0.05). §PInter values indicate between groups differences
(Student’s t test or Mann–Whitney U signed-rank test, P<0.050)
2451Eur J Nutr (2018) 57:2445–2455
1 3
percentage was not affected in the control group, but
there was an increase in EVOO group (0.68±0.46%
95% CI −0.30 to 1.65 vs. 1.45±0.36 95% CI 0.69–2.20;
Metabolic biomarkers
Serum glucose reduced in both groups after the intervention
without a significant difference between groups (P=0.811).
Despite no between-group changes in metabolic biomark-
ers, HDL-c reduced and IL-10 increased only in the control
group. On the other hand, EVOO was the only group in
which creatinine increased and alkaline phosphatase reduced
(Table3). There as positive correlation between changes
in total body fat and changes in alkaline phosphatase
(R2=0.488, P=0.005) and negative correlation between
changes in total body fat and changes in serum creatinine
(R2=−0.360, P=0.021).
This study was design to assess the effects of EVOO incor-
porated into an energy-restricted non-Mediterranean diet
program on body weight, body composition and metabolic
biomarkers in women with excess body fat. The main find-
ing of the present study is that the consumption of EVOO
increases total fat loss and reduces diastolic blood pressure
compared to the control soybean oil group. To the best of
our knowledge, this paper provides the first clinical evi-
dence that EVOO consumption increases body fat loss due
to energy-restricted program even when not incorporated
into a Mediterranean diet. Analysis of food consumption
during the experiment demonstrated that our high-fat break-
fasts significantly changed daily consumption of dietary fatty
acids. EVOO group increased body fat loss, which could be
considered independent of a greater caloric restriction in
EVOO than control group once difference between groups in
energy intake was not significant and insufficient to explain
Table 3 Metabolic biomarkers at baseline and change from baseline (95% CI) according to experimental groups
Values are mean±SE or median (interquartile range)
HOMA-IR homeostasis model assessment of insulin resistance [36], HDL-c high-density lipoprotein cholesterol, LDL-c low-density lipopro-
tein cholesterol, ALP alkaline phosphatase, AP alkaline phosphatase, Gamma GT γ-glutamyltransferase, AST aspartate amino transferase, ALT
alanine amino transferase, IL-8 interleukin-8, IL-1β interleukin-1β, IL-6 interleukin-6, IL-10 interleukin-10, TNF-α tumor necrosis factor-α, IL-
12p70 interleukin-12p70, PInter between-group Δ values (9week—baseline) are not significantly different (Student’s t test or Mann–Whitney U
signed-rank test, P>0.05)
Metabolic biomarkers Control (n=20) Extra virgin olive oil (n=21) PInter
Baseline Δ values 95% CI Baseline Δ values 95% CI
Glucose (mmol/L) 4.76±0.09 −0.13±0.05 −0.23 to −0.02 4.86 (0.50) −0.11 (0.39) −0.37 to −0.04 0.811
Insulin (pmol/L) 7.90 (3.80) 3.82 (35.6) −0.56 to 27.0 8.10 (4.20) −4.31±5.90 −16.7 to 8.20 0.060
HOMA−IR 1.61 (0.76) 0.08 (1.15) −0.08 to 0.76 1.92 (1.14) −0.19±0.22 −0.64 to 0.26 0.054
Triglycerides (mmol/L) 0.98±0.09 −0.02 (0.28) −0.24 to 0.06 1.27±0.13 −0.07±0.07 −0.23 to 0.09 0.579
Total cholesterol (mmol/L) 4.26±0.19 −0.14±0.08 −0.30 to 0.02 4.45±0.20 −0.20±0.12 −0.44 to 0.05 0.671
HDL-c (mmol/L) 1.19±0.06 −0.07±0.03 −0.14 to −0.01 1.31±0.07 −0.03±0.03 −0.10 to 0.03 0.385
LDL-c (mmol/L) 2.42±0.15 −0.06±0.06 −0.18 to 0.06 2.52±0.15 −0.04±0.08 −0.21 to 0.12 0.832
Triglycerides/HDL−c 0.90±0.12 0.00±0.13 −0.26 to 0.27 0.79 (0.55) 0.10±0.10 −0.11 to 0.31 0.548
Uric acid (µmol/L) 206±7.73 2.38±7.14 −11.9 to 16.7 209±8.92 −2.97±5.95 −14.9 to 9.52 0.579
Creatinine (µmol/L) 51.3±0.88 −0.00±1.77 −2.65 to 2.65 50.4±1.77 3.54±0.88 1.15 to 5.75 0.057
AP (IU/L) 61.1±3.47 −1.68±2.05 −5.98 to 2.62 63.7±4.89 −3.26±1.78 −7.00 to 0.47 0.564
Gamma GT (IU/L) 21.9±0.60 0.11±0.52 −0.98 to 1.20 19.1±1.43 −0.24±0.70 −1.72 to 1.25 0.691
AST (IU/L) 34.0±1.56 −0.95±2.09 −5.35 to 3.45 30.0 (14.0) −0.24±1.51 −3.40 to 2.92 0.782
ALT (IU/L) 16.0 (7.25) −2.06±1.06 −4.30 to 0.19 17.7±1.84 0.16±1.38 −2.74 to 3.06 0.219
IL-8 (pg/mL) 6.83±0.51 0.61±0.51 −0.48 to 1.69 8.07±0.78 0.27±0.70 −1.22 to 1.77 0.706
IL-1β(pg/mL) 0.98±0.25 0.06±0.23 −0.50 to 0.61 1.24±0.29 −0.28±0.14 −0.62 to 0.06 0.252
IL-6 (pg/mL) 1.74±0.25 −0.03±0.35 −0.80 to 0.73 1.76±0.22 0.16±0.26 −0.39 to 0.71 0.655
IL-10 (pg/mL) 0.86±0.08 0.189±0.08 0.01 to 0.37 1.11±0.14 0.05±0.09 −0.14 to 0.24 0.259
TNF- (pg/mL) 0.25±0.10 0.00 (0.00) −1.96 to 3.13 0.61 (0.45) 0.09±0.29 −0.65 to 0.84 0.905
IL-12p70 (pg/mL) 2.08±0.45 −0.14±0.47 −1.17 to 0.88 2.15±0.39 −0.10±0.31 −0.77 to 0.56 0.942
IL-10/IL-6 (pg/mL) 2.15±0.39 −0.39±0.29 −1.01 to 0.25 1.63±0.21 0.12±0.28 −0.49 to 0.72 0.227
2452 Eur J Nutr (2018) 57:2445–2455
1 3
such increase [39]. Furthermore, our results show that while
IL-10 increased only in the control group, HDL-c concentra-
tions reduced in that same group. On the other hand, serum
creatinine increased, alkaline phosphatase reduced, and
there was a trend for IL-1β reduction in the EVOO group
along the nine experimental weeks.
It has been widely suggested that the consumption of a
Mediterranean diet rich in olive oil can prevent type 2 dia-
betes mellitus [40, 41] metabolic syndrome [40] and obesity
[17, 40]. However, randomized clinical trials in which the
effect of olive oil on body weight/fat was investigated are
scarce and presented conflicting results [1820, 42]. In a
recent study [42] involving 7447 asymptomatic high-CVD
risk individuals, daily consumption of 50mL of EVOO for
4.8years associated with an unrestricted-calorie, high-vege-
table Mediterranean diet reduced body weight and promoted
less central adiposity gain compared with the consumption
of a low-fat diet. In our study, the daily consumption of
energy-restricted normal-fat diet containing 25mL of EVOO
reduced total body fat compared to 25mL/day of soybean
oil. Additionally, to the aforementioned study, our findings
support the prescription of EVOO not only for preventing
weight gain, but also for promoting body weight/fat loss.
The current hypothesis that EVOO could improve body
composition was mainly based in the effect of oleic acid
(C18:1) on stearoyl-CoA desaturase 1 (SCD1) [11]. This
enzyme catalyzes a key step in the endogenous biosynthesis
of MUFA from saturated fatty acids. The preferential sub-
strates for its action are palmitic acid and stearic acid, which
are converted by SCD1 into palmitoleic acid and oleic acid,
respectively [43]. The influence of increased SCD1 activity
on obesity is supported by studies using mice with natural
or SCD1-direct mutations. SCD1-deficient mice consume
25% more food but accumulate less fat and are consider-
ably thinner than normal mice [44, 45]. In addition, SCD1-
deficient animals consume more oxygen and have higher
rates of β-oxidation in liver and fat tissue [46]. The lack of
SCD1 also beneficially modulates the expression and activ-
ity of some genes related to adiposity [47]. According to
this hypothesis, SCD1 activity is regulated by the amount
of substrate and final product. Thus, while consumption of
the saturated fatty acids palmitic and stearic acid acts as sub-
strate stimulating SCD1 action and favoring obesity, oleic
acid down regulates SCD1 activity favoring weight loss [11].
The effect of EVOO consumption on SCD1 expression and
activity must be investigated in metagenomic studies.
In our study, EVOO significantly reduced (~5mmHg)
diastolic blood pressure compared to the control (soybean
oil). Soybean oil could be considered a good control for
assessing blood pressure due to its little effect on that vari-
able [48]. Therefore, despite the differences in baseline val-
ues observed in diastolic blood pressure, our results suggest
that EVOO contribute to hypertension control. The role of
EVOO in reducing blood pressure is supported by a grow-
ing body of scientific evidence [4649]. Despite the fact
that minor components characteristic of olive oil could con-
tribute to the cardioprotective activity of EVOO, such as
a-tocopherol, polyphenols, and other phenolic compounds,
Terés etal. [49] demonstrated that its high oleic acid con-
tent is responsible for the antihypertensive effects of olive
oil consumption. This effect is likely to be attributed to the
incorporation of oleic acid into cell membranes, which regu-
lates membrane lipid structure in such a way as to control
G protein-mediated signaling, causing a reduction in blood
pressure [49].
There is still no consensus about the role of EVOO
on dyslipidemia. While some studies reported beneficial
increase in HDL-c [49, 50] and reduction in LDL-c [51],
others showed no significant changes in lipid profile [47,
5255]. In our study, EVOO presented cholesterol-neutral
effect, since HDL-c reduced in the control group at the
end of the experiment. Our results corroborated with those
reported by [56], in which there was a decrease in HDL-c
concentrations after the consumption of~50g of soybean
oil and maintenance of HDL-c in response to the consump-
tion of similar amount of olive oil. The authors attributed
the reduction to soybean oil linoleic acid high content and
the maintenanceof HDL-c to the competition between olive
oil chylomicron remnants and HDL for hepatic lipase [56].
Thus, olive oil could prevent HDL-c postprandial decrease,
and maybe contribute for a more favorable lipid profile.
We observed a significant, but no clinically relevant
increase in serum creatinine in the EVOO group. This was
an unexpected result since creatinine was assessed as a bio-
marker of renal function, and we expected that EVOO could
protect kidneys from obese lipotoxicity [57]. However, we
believe that the increase in serum creatinine was a reflect of
lean mass preservation during the study since creatinine is
a lean mass content marker and EVOO was the only group
in which lean mass percentage increased at the end of the
experiment. On the other hand, there was a reduction in
alkaline phosphatase in EVOO. Despite the fact that alka-
line phosphatase is not specific from liver, data from animal
studies provide some evidences that polyphenols from olive
oil could improve liver function by reducing lipid peroxida-
tion in this tissue [58, 59]. Thus, the slight reduction in that
enzyme may reflect and improve in liver function. This result
deserves to be confirmed in individuals with non-alcoholic
fatty liver disease.
In our study, there was a significant increase in IL-10 in
the control group. Soybean oil was provided to the control
group to match fat consumption between groups, but was
responsible for an increased consumption of α-linolenic
acid (C18:3) in that group. Increased consumption of
α-linolenic acid can down-regulate inflammatory pathways
and reduce plasma levels of IL-10 [60]. In turn, EVOO
2453Eur J Nutr (2018) 57:2445–2455
1 3
showed a trend for IL-1β reduction. A very similar effect
of olive oil was observed in another study conducted by
Kremer etal. [61]. In that study, the effect of fish oil vs.
olive oil (placebo) on active human rheumatoid arthri-
tis was investigated. Olive oil consumption led to unex-
pected beneficial effects on the improvement of clinical
aspects of the disease. These benefits were associated with
decreased macrophage IL-1 production although not to
the same extent as the fish oil group [61]. As IL-1β has
potent and vast pro-inflammatory effect over a number of
cells, including macrophages, monocytes, and dendritic
cells [62], the role of EVOO on IL-1β deserves to be fur-
ther explored.
Our study has several strengths, including the rigorous
subjects’ eligibility criteria, the use of DXA for body com-
position assessments, use of double blind protocol, double
digitation of data, controlled breakfasts consumption, and
evaluation of diet compliance. However, the study also has
limitations. This study showed a relatively high attrition
rate due to secondary reasons not related to the study pro-
tocol. Despite the fact that we selected woman with very
high body fat content (~48% at baseline), they were also
young and it is possible that we were not able to detect
the influence of dietary treatment in some metabolic bio-
markers (e.g., some cytokines which were not detected).
Furthermore, women are more prone to present changes in
anthropometric parameters and body compositions due to
menstrual cycle. Despite our efforts to reduce the influence
of water retention, we cannot assure that our results were
not affected by participant hormonal fluctuations. Finally,
the interference of EVOO higher diastolic blood pressure
at baseline in our results cannot be totally neglected.
Daily consumption of 25mL of extra virgin oil (EVOO)
associated with an energy-restricted Western-diet
increased body fat loss and reduced blood pressure.
The beneficial effects of EVOO were independent of an
increase in caloric restriction, indicating a positive direct
role of this oil on adiposity. EVOO also increased serum
creatinine, reduced hepatic alkaline phosphatase, and
tended to reduce IL-1β concentrations. The intriguing
impact of EVOO on SCD1 expression and activity must
be better explored in metagenomic studies.
Acknowledgements We thank Fundação de Amparo à Pesquisa do
Estado de Minas Gerais—FAPEMIG (protocol number: APQ-01877-
1). The Coordenação de Aperfeiçoamento de Pessoal de Nível Supe-
rior—CAPES and Conselho Nacional de Desenvolvimento Científico
e Tecnológico—CNPq for providing research grants to the authors. We
thank Bioclin® for providing biochemical assays kits. These companies
had no role in design, analysis, or writing of this manuscript.
Compliance with ethical standards
Conflict of interest The authors declare that they have no conflict
of interest.
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... Escalante et al. reported that topically applying Lipoxyderm, a lotion containing aminophylline, caffeine, Yohimbe, l-carnitine, and C. asiatica (gotu kola), twice daily for 28 days significantly decreased THC, thigh skinfold thickness, and thigh FM compared to the placebo [69]. Galvão Cândido et al. concluded that daily high-fat breakfasts containing 25 mL of extra virgin O. europaea (olive) oil over nine consecutive weeks led to higher fat loss [70]. Extra virgin olive oil also increased serum creatinine, decreased hepatic alkaline phosphatase, and generally reduced interleukin-1β (IL-1β) levels. ...
... Artichoke extract, GE, GSE, OPE, mangosteen extract, S. platensis powder, and flaxseed oil decreased high-sensitivity C-reactive protein (hsCRP) levels [14][15][16]22,52,54,71]. GO, canola oil, high-oleic-acid canola oil, and extra virgin olive oil reduced IL-1β [50,70,73]. BBT increased IL-10 [11]. ...
... Laboratory tests were left blank in the table when the obesity indicators were nonsignificant, the parameters were unrelated to obesity or lipid metabolism, or there were no serological indicators. Moreover, a few studies were the first clinical trials on their target compound [9,23,53,57,58,68,70,72]. Therefore, the drug dosage was determined based on the results of animal experiments since there were no human reference data, leading to relatively low confidence in their experimental results. ...
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Obesity is a global issue faced by many individuals worldwide. However, no drug has a pronounced effect with few side effects. Green tea, a well-known natural product, shows preventive effects against obesity by decreasing lipogenesis and increasing fat oxidation and antioxidant capacity. In contrast, other natural products are known to contribute to obesity. Relevant articles published on the therapeutic effect of natural products on obesity were retrieved from PubMed, Web of Science, and Scopus. The search was conducted by entering keywords such as “obesity”, “natural product”, and “clinical trial”. The natural products were classified as single compounds, foods, teas, fruits, herbal medicines—single extract, herbal medicines—decoction, and herbal medicines—external preparation. Then, the mechanisms of these medicines were organized into lipid metabolism, anti-inflammation, antioxidation, appetite loss, and thermogenesis. This review aimed to assess the efficacy and mechanisms of effective natural products in managing obesity. Several clinical studies reported that natural products showed antiobesity effects, including Coffea arabica (coffee), Camellia sinensis (green tea), Caulerpa racemosa (green algae), Allium sativum (garlic), combined Ephedra intermedia Schrenk, Thea sinensis L., and Atractylodes lancea DC extract (known as Gambisan), Ephedra sinica Stapf, Angelica Gigantis Radix, Atractylodis Rhizoma Alba, Coicis semen, Cinnamomi cortex, Paeoniae radix alba, and Glycyrrhiza uralensis (known as Euiiyin-tang formula). Further studies are expected to refine the pharmacological effects of natural products for clinical use.
... Sixteen RCTs examined the effect of EVOO on blood pressure [39,41,43,44,[46][47][48]51,55,60,62,63,[65][66][67]70]. Of these, six included the total phenol content of the EVOO studied [39,41,48,62,63,68]. ...
... For the seven studies that included normotensive participants, three studies reported the olive oil used as "extra virgin olive oil" [51,60,66]. Two reported EVOO lowering only DBP compared with corn [60] or soybean oil [51], and one reported only lowering SBP compared with an intervention that was corn oil, soybean oil, and butter [66]. ...
... For the seven studies that included normotensive participants, three studies reported the olive oil used as "extra virgin olive oil" [51,60,66]. Two reported EVOO lowering only DBP compared with corn [60] or soybean oil [51], and one reported only lowering SBP compared with an intervention that was corn oil, soybean oil, and butter [66]. Three reported a total phenol content of 366 mg/kg, and DBP was lowered compared with refined olive oil [39,41,62]. ...
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Most chronic diseases are preventable with a healthy diet, although there is debate about the optimal dietary approach. Increasingly more countries are focusing on food-based guidelines rather than the traditional nutrient-based approach. Although there is good agreement on plant foods, controversy remains about the types and amounts of fats and oils. This narrative review aims to systematically summarize and evaluate the latest evidence on the protective effects of extra virgin olive oil (EVOO) on disease risk factors. A systematic search of the relevant literature using PubMed, Cochrane Library, and Embase databases was conducted for the years 2000 through December 2022. A narrative synthesis was then undertaken. Of 281 retrieved articles, 34 articles fulfilled our inclusion criteria and were included. Compared with other dietary fats and low-fat diets, EVOO is superior in the management of clinical biomarkers including lowering blood pressure and LDL-c, increasing protective HDL-c, improving glycemic control, and weight management. The protective effects of EVOO are likely due to its polyphenol content rather than the monounsaturated fat content. It is therefore important to promote the regular use of EVOO in the context of healthy dietary patterns such as the Mediterranean diet for maximal health benefit.
... The present analysis included a total of 2175 subjects, with the number of participants in each individual study ranging from 11 to 195. In total, 12 studies included healthy subjects [19,[28][29][30][31][32][33][34][35][36][37][38], 9 studies included subjects with hyperlipidemia [16,17,20,[39][40][41][42][43][44][45], and other trials were conducted on patients with obesity [17,18,41,[46][47][48][49], type 2 diabetes [50][51][52], nonalcoholic fatty liver [53,54], metabolic syndrome [21,55], polycystic ovary syndrome [56,57], hypertension [58], cardiovascular disease [59], chronic peripheral artery occlusive disease [60], peripheral vascular disease [61] or hyperfibrinogenaemia [62]. The design of 30 trials was parallel and 10 studies used a crossover design. ...
... The present analysis included a total of 2175 subjects, with the number of participants in each individual study ranging from 11 to 195. In total, 12 studies included healthy subjects [19,[28][29][30][31][32][33][34][35][36][37][38], 9 studies included subjects with hyperlipidemia [16,17,20,[39][40][41][42][43][44][45], and other trials were conducted on patients with obesity [17,18,41,[46][47][48][49], type 2 diabetes [50][51][52], nonalcoholic fatty liver [53,54], metabolic syndrome [21,55], polycystic ovary syndrome [56,57], hypertension [58], cardiovascular disease [59], chronic peripheral artery occlusive disease [60], peripheral vascular disease [61] or hyperfibrinogenaemia [62]. The design of 30 trials was parallel and 10 studies used a cross-over design. ...
... The current study showed that LA increases HDL-C less compared to the other control groups. Some studies reported that a high PUFA intake is associated with lower HDL-C levels compared to high SFA and MUFA intake [18,32,48]. Similar results were revealed by Ghobadi, showing that OA has a greater beneficial effect on HDL-C compared to LA [71]. ...
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Th aim of this meta-analysis was to elucidate whether dietary linoleic acid (LA) supplementation affected blood lipid profiles, including triglycerides (TG), total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol (LDL-C), compared with other fatty acids. Embase, PubMed, Web of Science and the Cochrane Library databases, updated to December 2022, were searched. The present study employed weighted mean difference (WMD) and a 95% confidence interval (CI) to examine the efficacy of the intervention. Out of the 3700 studies identified, a total of 40 randomized controlled trials (RCTs), comprising 2175 participants, met the eligibility criteria. Compared with the control group, the dietary intake of LA significantly decreased the concentrations of LDL-C (WMD: −3.26 mg/dL, 95% CI: −5.78, −0.74, I2 = 68.8%, p = 0.01), and HDL-C (WMD: −0.64 mg/dL, 95% CI: −1.23, −0.06, I2 = 30.3%, p = 0.03). There was no significant change in the TG and TC concentrations. Subgroup analysis showed that the LA intake was significantly reduced in blood lipid profiles compared with saturated fatty acids. The effect of LA on lipids was not found to be dependent on the timing of supplementation. LA supplementation in an excess of 20 g/d could be an effective dose for lowering lipid profiles. The research results provide further evidence that LA intake may play a role in reducing LDL-C and HDL-C, but not TG and TC.
... Three studies showed that OO may be beneficial in reducing elevated blood pressure [59][60][61]. The regular consumption of an EVOO rich in phenolic compounds (366 mg/kg PC) by healthy individuals was found to reduce the systolic blood pressure and maintain the diastolic blood pressure compared to pre-intervention values as well as an EVOO low in phenolic compounds (2.7 mg/kg PC), by down regulation of the angiotensin I-converting enzyme (ACE), nuclear receptor subfamily 1, group H, member 2 (NR1H2) and Interleukin 8 receptor alpha (IL8RA) gene expressions, blood pressure-related genes involved in the renin-angiotensin-aldosterone system [59]. ...
... The regular consumption of an EVOO rich in phenolic compounds (366 mg/kg PC) by healthy individuals was found to reduce the systolic blood pressure and maintain the diastolic blood pressure compared to pre-intervention values as well as an EVOO low in phenolic compounds (2.7 mg/kg PC), by down regulation of the angiotensin I-converting enzyme (ACE), nuclear receptor subfamily 1, group H, member 2 (NR1H2) and Interleukin 8 receptor alpha (IL8RA) gene expressions, blood pressure-related genes involved in the renin-angiotensin-aldosterone system [59]. In a randomized controlled trial, daily consumption of the same amount of EVOO (25 mL/day) associated with an energy-restricted Western diet, for nine weeks, decreased the diastolic blood pressure and reduced body fat in overweight women [60]. Moreover, OO supplementation (3 g/day) reduced the resting systolic and diastolic blood pressure in young healthy men and women [61]. ...
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The Mediterranean diet is a healthy dietary pattern whose main characteristic is olive oil consumption. The potential health benefits of olive oil have been extensively investigated and the present review provides the more recent clinical evidence supporting the positive impact of olive oil intake on human health. PubMed (n = 227) and Scopus (n = 308) databases were searched for published clinical studies in English over the past six years (October 2016 to December 2022), following key word searches of “olive oil” and “health”. Major findings associated olive oil with antioxidant and anti-inflammatory effects, improvement in endothelial function and lipid profile, prevention of obesity, diabetes, cardiovascular and neurodegenerative diseases, and modulation of the gut microbiota. These benefits are attributed to the nutritional composition of olive oil, which has a high content of monounsaturated fatty acids (MUFA) (oleic acid in particular) and minor compounds such as polyphenols (oleuropein and hydroxytyrosol). Although additional research continues to be required, the more recently generated evidence supports the potential of olive oil to contribute beneficially to health and to the prevention and management of a variety of non-communicable diseases, as a consequence of the synergism between its components’ complexity.
... Moreover, some of the clinical studies using EVOO intake are conducted with specific groups of pathologies, such as obesity [32] or individuals at a higher risk of CVD [33,34]. Fewer studies have addressed the effect of EVOO in healthy individuals, without any established disease, and explored its role in analytical parameters and body composition [18,35]; most of them have used intervention periods of 12 weeks to 3 years on healthy, or unhealthy, individuals. ...
... Candido et al., in a randomized controlled study, showed that EVOO reduced body fat mass and improved blood pressure when included in energy-restricted programs for obesity treatment [32]. On the contrary, our study did not find changes in any anthropometric parameters. ...
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(1) Background: Extra virgin olive oil (EVOO) is studied mostly for its health benefits in preventing non-communicable chronic diseases, particularly within a Mediterranean dietary pattern. However, few studies have addressed the effect of EVOO in healthy individuals, prior to an established disease. This study aims to evaluate the impact of Northern Portuguese polyphenol-rich EVOO (NPPR-EVOO) consumption on various important clinical parameters in healthy adult volunteers. (2) Methods: This quasi-experimental intervention study assessed the impact of NPPR-EVOO for a period of 100 days. Serum total cholesterol, HbA1c, HDL-c, LDL-c, and CRP, and anthropometric measures—waist and hip perimeters, hand grip strength, and body fat—were assessed and food logs were analyzed. (3) Results: Serum HbA1c (5.12 ± 0.32%; 4.93 ± 0.24, p = 0.000) and LDL-c (96.50 ± 28.57 mg/dL; 87.41 ± 31.38 mg/dL, p = 0.017) significantly decreased following NPPR-EVOO. Also, daily energy significantly increased, but no changes in other dietary parameters, or anthropometry, were seen. Adherence to the Mediterranean diet did not explain the differences found in individuals regarding serum lipid profile and HbA1c, reinforcing the role of EVOO’s effect. (4) Conclusions: NPPR-EVOO lowered the serum levels of LDL cholesterol and HbA1c, providing clues on the effect of EVOO-putative health benefits. These results pave the way for a deeper exploration of EVOO as a functional food.
... Also, prolonged 8week consumption of diets containing polyphenol-rich OO (∼30 mg/day) has been associated with decreased BP and improvement in endothelial function in women with highnormal or stage 1 essential hypertension [31]. Similarly, in women with excess body fat, the ingestion of 25 mL of extra virgin OO daily for 8 weeks has been shown to reduce systolic and diastolic BP while improving body fat [32]. Furthermore, MedDiet supplemented with extra virgin OO (52 g/day for 1 year) decreased BP in hypertensive women [33]. ...
... Taken together, polyphenol-rich food oils seem to represent a non-homogenous group with diverse effects on cardiovascular and cardiometabolic health that are mainly positive, but might be also neutral, and even negative ( Table 1, Ref. [ [16][17][18]21,22,[30][31][32][33][34][36][37][38][39][40]43,45,[47][48][49]52,55,56,59,65,66,[69][70][71][72][73]77,78,[80][81][82][83][84][89][90][91][93][94][95][110][111][112][113][114][120][121][122][123][124]148,159,160,162,166,167,169,179,189,201,203,206,[209][210][211]). ...
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A variety of vegetable and fruit derived food oils are considered beneficial for human health due to their content of functional components including their positive effects in cardiovascular system. In addition to the favorable ratio of unsaturated versus saturated fatty acids, some of these oils include also other health beneficial compounds such as vitamins, minerals, pigments, enzymes and phenolic compounds. Particularly polyphenols have been documented to exert numerous positive effects in cardiovascular system including their anti-hypertensive, anti-atherogenic as well as cardio- and vasculo- protective effects in subjects suffering from various cardiovascular and cardiometabolic diseases, likely via their antioxidant, anti-inflammatory, anti-coagulant, anti-proliferative and anti-diabetic properties. However, it has not been proven so far whether the positive cardiovascular effects of polyphenol-rich food oils are, and to what measure, attributed to their phenolic content. Thus, the current review aims to summarize the main cardiovascular effects of major polyphenol-rich food oils including olive, flaxseed, soybean, sesame and coconut oils, and to uncover the role of their phenolic compounds in these effects.
... Additionally, although we did not measure energy expenditure changes induced by the diets, the HFD-O may have produced a positive effect on this parameter. Indeed, olive oil has been previously shown to increase energy expenditure in both rodents and humans 52,53 . ...
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N-oleoylglycine (OlGly), a lipid derived from the basic component of olive oil, oleic acid, and N-oleoylalanine (OlAla) are endocannabinoid-like mediators. We report that OlGly and OlAla, by activating the peroxisome proliferator-activated receptor alpha (PPARα), reduce the rewarding properties of a highly palatable food, dopamine neuron firing in the ventral tegmental area, and the obesogenic effect of a high-fat diet rich in lard (HFD-L). An isocaloric olive oil HFD (HFD-O) reduced body weight gain compared to the HFD-L, in a manner reversed by PPARα antagonism, and enhanced brain and intestinal OlGly levels and gut microbial diversity. OlGly or OlAla treatment of HFD-L mice resulted in gut microbiota taxonomic changes partly similar to those induced by HFD-O. We suggest that OlGly and OlAla control body weight by counteracting highly palatable food overconsumption, and possibly rebalancing the gut microbiota, and provide a potential new mechanism of action for the obeso-preventive effects of olive oil-rich diets.
Diet composition has a great impact on body composition. Several studies have suggested a beneficial effect of adding olive oil to a calorie-restricted diet as a weight loss strategy. However, there is no clear direction regarding the effect of olive oil on body fat distribution. This systematic review with meta-analysis aims to investigate the effect of olive oil consumption (for cooking or as a supplement) on body fat distribution in adults. The present study was conducted following the recommendations of the Cochrane Handbook for Systematic Reviews of Interventions and was registered in the International Prospective Register of Systematic Reviews (PROSPERO CRD42021234652). All randomized clinical trials of parallel or crossover design found in PubMed (via MEDLINE), EMBASE, Web of Science and Scopus databases that compared the effects of olive oil with other oils on body fat distribution in adults were included. 52 articles were included. The results indicate that the consumption of olive oil does not seem to alter the distribution of body fat, despite a small indication that supplementation in capsules can increase adipose mass (Mean Difference = 0.28 kg, 95% CI [-0.27, 0.83]; between-groups difference p = 0.59) and waist circumference (mean difference = 1.74 kg, 95% CI [0.86, 1.62]; between-groups difference p < 0.01) and decrease its auxiliary culinary use (mean difference = -0.32 kg, 95% CI [-0.90, 0.26]). Lean mass responds negatively to OO the higher the dose (slope = -0.61, 95% CI [-1.01, -0.21], p = 0.003) and time offered (slope = -0.8822, 95% CI [-1.44, -0.33], p = 0.002). In conclusion, this systematic review showed that OO ingestion in different delivery vehicles, dosages, and durations can interfere body composition. It is important to emphasize that some other aspects of the population and the intervention, that were not possible to be explored in the analysis, could confound the real effects of OO on body composition.
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Varios estudios mencionan que el aceite de oliva extra virgen ha mostrado beneficios de acuerdo a cómo ac-túan sus ácidos grasos monoinsaturados ayudando a incrementar las lipoproteínas de alta densidad (HdL) y promover la inhibición de la oxidación de las lipo-proteínas de baja densidad (LdL). El aceite de oliva extra virgen contiene antioxidantes llamados polife-noles y tocoferoles, los cuales contribuyen a prevenir el desarrollo del estrés oxidativo. El aceite de oliva extra virgen es básicamente el único de los aceites que con-tiene una alta cantidad de estos compuestos antioxi-dantes, debido a que los demás aceites comestibles los pierden en el proceso de refinado.Actualmente, el colesterol alto o hipercolesterole-mia se considera como uno de los factores de riesgo más importantes relacionados al desarrollo de enfer-medades cardiovasculares, pues incrementa el riesgo de infarto o derrames cerebrales, ya que puede limi-tar la irrigación sanguínea. Usualmente el nivel alto de colesterol no presenta síntomas y únicamente puede ser detectado por exámenes de sangre. El tratamiento para esta enfermedad se basa en medicamentos y una dieta balanceada acompañada de ejercicio físico.Años atrás se creía que el consumo de grasas era muy perjudicial para la salud. Hoy en día existen estu-dios que demuestran que una dieta adecuada en cuan-to a qué tipo de grasa se consume puede contribuir a beneficiar la salud y a prevenir enfermedades como, en este caso, la hipercolesterolemia. En esta revisión se observó que el aceite de oliva extra virgen tuvo efectos beneficiosos al disminuir los niveles de coles-terol LdL.
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Background: Because of the high density of fat, high-fat diets are perceived as likely to lead to increased bodyweight, hence health-care providers are reluctant to recommend them to overweight or obese individuals. We assessed the long-term effects of ad libitum, high-fat, high-vegetable-fat Mediterranean diets on bodyweight and waist circumference in older people at risk of cardiovascular disease, most of whom were overweight or obese. Methods: PREDIMED was a 5 year parallel-group, multicentre, randomised, controlled clinical trial done in primary care centres affiliated to 11 hospitals in Spain. 7447 asymptomatic men (aged 55-80 years) and women (aged 60-80 years) who had type 2 diabetes or three or more cardiovascular risk factors were randomly assigned (1:1:1) with a computer-generated number sequence to one of three interventions: Mediterranean diet supplemented with extra-virgin olive oil (n=2543); Mediterranean diet supplemented with nuts (n=2454); or a control diet (advice to reduce dietary fat; n=2450). Energy restriction was not advised, nor was physical activity promoted. In this analysis of the trial, we measured bodyweight and waist circumference at baseline and yearly for 5 years in the intention-to-treat population. The PREDIMED trial is registered with, number ISRCTN35739639. Findings: After a median 4·8 years (IQR 2·8-5·8) of follow-up, participants in all three groups had marginally reduced bodyweight and increased waist circumference. The adjusted difference in 5 year changes in bodyweight in the Mediterranean diet with olive oil group was -0·43 kg (95% CI -0·86 to -0·01; p=0·044) and in the nut group was -0·08 kg (-0·50 to 0·35; p=0·730), compared with the control group. The adjusted difference in 5 year changes in waist circumference was -0·55 cm (-1·16 to -0·06; p=0·048) in the Mediterranean diet with olive oil group and -0·94 cm (-1·60 to -0·27; p=0·006) in the nut group, compared with the control group. Interpretation: A long-term intervention with an unrestricted-calorie, high-vegetable-fat Mediterranean diet was associated with decreases in bodyweight and less gain in central adiposity compared with a control diet. These results lend support to advice not restricting intake of healthy fats for bodyweight maintenance. Funding: Spanish Government, CIBERobn, Instituto de Salud Carlos III, Hojiblanca, Patrimonio Comunal Olivarero, California Walnut Commission, Borges SA, and Morella Nuts.
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Purpose: Serum nitric oxide (NO) reduction and increased endothelin-1 (ET-1) play a pivotal role in endothelial dysfunction and hypertension. Considering that traditional Mediterranean diet (TMD) reduces blood pressure (BP), the aim of this study was to analyze whether TMD induced changes on endothelial physiology elements such as NO, ET-1 and ET-1 receptors which are involved in BP control. Methods: Non-smoking women with moderate hypertension were submitted for 1 year to interventions promoting adherence to the TMD, one supplemented with extra virgin olive oil (EVOO) and the other with nuts versus a control low-fat diet (30 participants/group). BP, NO, ET-1 and related gene expression as well as oxidative stress biomarkers were measured. Results: Serum NO and systolic BP (SBP) or diastolic BP (DBP) were negatively associated at baseline, as well as between NO and ET-1. Our findings also showed a DBP reduction with both interventions. A negative correlation was observed between changes in NO metabolites concentration and SBP or DBP after the intervention with TMD + EVOO (p = 0.033 and p = 0.044, respectively). SBP reduction was related to an impairment of serum ET-1 concentrations after the intervention with TMD + nuts (p = 0.008). We also observed changes in eNOS, caveolin 2 and ET-1 receptors gene expression which are related to NO metabolites levels and BP. Conclusions: The changes in NO and ET-1 as well as ET-1 receptors gene expression explain, at least partially, the effect of EVOO or nuts on lowering BP among hypertensive women.
Responding to the expansion of scientific knowledge about the roles of nutrients in human health, the Institute of Medicine has developed a new approach to establish Recommended Dietary Allowances (RDAs) and other nutrient reference values. The new title for these values Dietary Reference Intakes (DRIs), is the inclusive name being given to this new approach. These are quantitative estimates of nutrient intakes applicable to healthy individuals in the United States and Canada. This new book is part of a series of books presenting dietary reference values for the intakes of nutrients. It establishes recommendations for energy, carbohydrate, fiber, fat, fatty acids, cholesterol, protein, and amino acids. This book presents new approaches and findings which include the following: The establishment of Estimated Energy Requirements at four levels of energy expenditure Recommendations for levels of physical activity to decrease risk of chronic disease The establishment of RDAs for dietary carbohydrate and protein The development of the definitions of Dietary Fiber, Functional Fiber, and Total Fiber The establishment of Adequate Intakes (AI) for Total Fiber The establishment of AIs for linolenic and a-linolenic acids Acceptable Macronutrient Distribution Ranges as a percent of energy intake for fat, carbohydrate, linolenic and a-linolenic acids, and protein Research recommendations for information needed to advance understanding of macronutrient requirements and the adverse effects associated with intake of higher amounts Also detailed are recommendations for both physical activity and energy expenditure to maintain health and decrease the risk of disease. © 2002/2005 by the National Academy of Sciences. All rights reserved.
Objectives: To review the contribution of the Nurses' Health Studies (NHS and NHS II) in addressing hypotheses regarding risk factors for and consequences of obesity. Methods: Narrative review of the publications of the NHS and NHS II between 1976 and 2016. Results: Long-term NHS research has shown that weight gain and being overweight or obese are important risk factors for type 2 diabetes, cardiovascular diseases, certain types of cancers, and premature death. The cohorts have elucidated the role of dietary and lifestyle factors in obesity, especially sugar-sweetened beverages, poor diet quality, physical inactivity, prolonged screen time, short sleep duration or shift work, and built environment characteristics. Genome-wide association and gene-lifestyle interaction studies have shown that genetic factors predispose individuals to obesity but that such susceptibility can be attenuated by healthy lifestyle choices. This research has contributed to evolving clinical and public health guidelines on the importance of limiting weight gain through healthy dietary and lifestyle behaviors. Conclusions: The NHS cohorts have contributed to our understanding of the risk factors for and consequences of obesity and made a lasting impact on clinical and public health guidelines on obesity prevention. (Am J Public Health. Published online ahead of print July 26, 2016: e1-e7. doi:10.2105/AJPH.2016.303326).
This is the first in a series of articles devoted to a simplified description of experimental design, statistical analysis, and interpretation, using actual laboratory data as examples. The present article deals with sample size calculation for a single factor experiment and for a repeated measures design.
For several years the European Society of Hypertension (ESH) and the European Society of Cardiology (ESC) decided not to produce their own guidelines on the diagnosis and treatment of hypertension but to endorse the guidelines on hypertension issued by the World Health Organization (WHO) and International Society of Hypertension (ISH)1,2 with some adaptation to reflect the situation in Europe. However, in 2003 the decision was taken to publish ESH/ESC specific guidelines3 based on the fact that, because the WHO/ISH Guidelines address countries widely varying in the extent of their health care and availability of economic resource, they contain diagnostic and therapeutic recommendations that may be not totally appropriate for European countries. In Europe care provisions may often allow a more in-depth diagnostic assessment of cardiovascular risk and organ damage of hypertensive individuals as well as a wider choice of antihypertensive treatment. The 2003 ESH/ESC Guidelines3 were well received by the clinical world and have been the most widely quoted paper in the medical literature in the last two years.4 However, since 2003 considerable additional evidence on important issues related to diagnostic and treatment approaches to hypertension has become available and therefore updating of the previous guidelines has been found advisable. In preparing the new guidelines the Committee established by the ESH and ESC has agreed to adhere to the principles informing the 2003 Guidelines, namely 1) to try to offer the best available and most balanced recommendation to all health care providers involved in the management of hypertension, 2) to address this aim again by an extensive and critical review of the data accompanied by a series of boxes where specific recommendations are given, as well as by a concise set of practice recommendations to be published soon thereafter as already done in 2003; …
Consumption of olive oil within the Mediterranean diet has been long known to have many health benefits. However, only over the last decade has epidemiological research confirmed its protective role against developing several chronic diseases. The objective of this review was to give an overview of the state of art epidemiological evidence concerning the relationship between olive oil and key public health outcomes including mortality, CVD, diabetes, metabolic syndrome (MetS), obesity and cancer, with a particular focus on recent results from cohort studies and dietary intervention trials. Recent epidemiological research has shown that regular consumption of olive oil is associated with increased longevity. This benefit is partly due to the olive oil's unequivocal cardio-protective role. There is converging evidence on the benefits of olive oil for preventing several CVD risk factors, including diabetes, MetS and obesity. Olive oil is also implicated in preventing certain cancers, with the most promising findings for breast and digestive tract cancers, although the data are still not entirely consistent and mainly from case-control studies. These health benefits are supported by strong mechanistic evidence from experimental studies, demonstrating that specific components of olive oil have antihypertensive, antithrombotic, antioxidant, antiinflammatory and anticarcinogenic action. Despite the accumulating epidemiological research, there is still a lack of consistent results from high-quality studies for many health outcomes (i.e. certain cancers and metabolism-related disorders). Further research is mandatory, above all from prospective studies and randomised dietary intervention trials when feasible, to confirm some of the still potential health benefits.