The hemodynamic effects of rebaudioside A in healthy adults with normal and low-normal blood pressure

Abstract

Rebaudioside A and stevioside are steviol glycosides extracted from the plant Stevia rebaudiana Bertoni and are used in several countries as food and beverage sweeteners. This randomized, double-blind trial evaluated the hemodynamic effects of 4weeks consumption of 1000mg/day rebaudioside A vs. placebo in 100 individuals with normal and low-normal systolic blood pressure (SBP) and diastolic blood pressure (DBP). Subjects were predominantly female (76%, rebaudioside A and 82%, placebo) with a mean age of approximately 41 (range 18-73) years. At baseline, mean resting, seated SBP/DBP was 110.0/70.3mmHg and 110.7/71.2mmHg for the rebaudioside A and placebo groups, respectively. Compared with placebo, rebaudioside A did not significantly alter resting, seated SBP, DBP, mean arterial pressure (MAP), heart rate (HR) or 24-h ambulatory blood pressures responses. These results indicate that consumption of as much as 1000mg/day of rebaudioside A produced no clinically important changes in blood pressure in healthy adults with normal and low-normal blood pressure.

Full text

The hemodynamic effects of rebaudioside A in healthy adults with normal and
low-normal blood pressure
K.C. Maki
a
, L.L. Curry
b
, M.C. Carakostas
c
, S.M. Tarka
d
, M.S. Reeves
a
, M.V. Farmer
e
, J.M. McKenney
f
,
P.D. Toth
g
, S.L. Schwartz
h
, B.C. Lubin
i
, M.R. Dicklin
a
, A.C. Boileau
b,*
, J.D. Bisognano
j
a
Provident Clinical Research, 1000 West 1st Street, Bloomington, IN, United States
b
Cargill, Incorporated, Food Ingredients and Systems North America, 15407 McGinty Road W, Wayzata, MN 55391, United States
c
The Coca-Cola Company, 1 Coca-Cola Plaza, Atlanta, GA, United States
d
The Tarka Group, Incorporated, 210 North Old Stone House Road, Carlisle, PA, United States
e
Meridien Research, 4751 North 66th Street, St. Petersburg, FL, United States
f
National Clinical Research, 2809 Emerywood Parkway, Suite 14, Incorporated, Richmond, VA, United States
g
Midwest Institute for Clinical Research, 8935 North Meridian Street, Indianapolis, IN, United States
h
DGD Research, 5107 Medical Drive, San Antonio, TX, United States
i
Hampton Roads Center for Clinical Research, 885 Kempsville Road, Suite 221, Norfolk, VA, United States
j
University of Rochester Medical Center, 601 Elmwood Avenue, Rochester, NY, United States
article info
Article history:
Received 29 November 2007
Accepted 28 April 2008
Keywords:
Rebaudioside A
Rebiana
Blood pressure
Steviol glycosides
abstract
Rebaudioside A and stevioside are steviol glycosides extracted from the plant Stevia rebaudiana Bertoni
and are used in several countries as food and beverage sweeteners. This randomized, double-blind trial
evaluated the hemodynamic effects of 4 weeks consumption of 1000 mg/day rebaudioside A vs. placebo
in 100 individuals with normal and low-normal systolic blood pressure (SBP) and diastolic blood pressure
(DBP). Subjects were predominantly female (76%, rebaudioside A and 82%, placebo) with a mean age of
41 (range 18–73) years. At baseline, mean resting, seated SBP/DBP was 110.0/70.3 mmHg and 110.7/
71.2 mmHg for the rebaudioside A and placebo groups, respectively. Compared with placebo, rebaudio-
side A did not significantly alter resting, seated SBP, DBP, mean arterial pressure (MAP), heart rate (HR) or
24-h ambulatory blood pressures responses. These results indicate that consumption of as much as
1000 mg/day of rebaudioside A produced no clinically important changes in blood pressure in healthy
adults with normal and low-normal blood pressure.
Ó2008 Elsevier Ltd. All rights reserved.
1. Introduction
Rebaudioside A and stevioside are naturally occurring steviol
glycosides from the leaves of the plant Stevia rebaudiana Bertoni
(JECFA, 2005). Stevia extracts have been used for many years as
high-intensity sweeteners in several countries, primarily in South
America and Asia. Stevioside and rebaudioside A differ by one addi-
tional glucose moiety on rebaudioside A. Both are metabolized to
steviol in the gastrointestinal tract (JECFA, 2005). Because of the
similarities in their metabolism, rebaudioside A and stevioside
are expected to produce similar physiological effects.
Steviol glycosides have been reported to have antihypertensive
properties in animals and humans (Melis and Sainati, 1991a,b; Me-
lis, 1992a,b; Chan et al., 1998; Hsieh et al., 2003; Jeppesen et al.,
2003; Liu et al., 2003). Results from long-term clinical trials (1–
2 years) in China studying men and women with mild to moderate
essential hypertension have suggested antihypertensive effects of
stevioside at intakes of 750 and 1500 mg/day (Chan et al., 2000;
Hsieh et al., 2003). However, other studies have not shown mea-
surable effects of steviol glycosides on blood pressure in humans.
Geuns et al. (2007) reported that administration of stevioside
(750 mg/day for 3 days) failed to significantly alter blood pressure
in nine subjects with normal blood pressure. Ferri et al. (2006) also
reported a lack of any antihypertensive effect of stevioside in
patients with untreated, mild hypertension following 6 weeks of
stevioside administration at dosages up to 15.0 mg kg
1
day
1
.
Most studies assessing antihypertensive properties have evalu-
ated stevioside, steviol, or mixtures of steviol glycosides (i.e., Stevia
0278-6915/$ - see front matter Ó2008 Elsevier Ltd. All rights reserved.
doi:10.1016/j.fct.2008.04.040
Abbreviations: ABPM, ambulatory blood pressure monitor; BMI, body mass
index; bpm, beats per minute; d, day; DBP, diastolic blood pressure; dL, deciliter;
FAO, Food and Agriculture Organization of the United Nations; HR, heart rate;
JECFA, Joint FAO/WHO Expert Committee on Food Additives; kg, kilogram; m
2
,
meters squared; MAP, mean arterial pressure; mg, milligram; mmHg, millimeters
mercury; min, minute; n, number; NHANES, National Health and Nutrition
Examination Survey; oz, ounce; SBP, systolic blood pressure; SEM, standard error
of the mean; t, time; WHO, World Health Organization.
*Corresponding author. Tel.: +1 952 742 4262; fax: +1 952 742 7573.
E-mail address: Amy_Boileau@cargill.com (A.C. Boileau).
Food and Chemical Toxicology 46 (2008) S40–S46
Contents lists available at ScienceDirect
Food and Chemical Toxicology
journal homepage: www.elsevier.com/locate/foodchemtox

extracts). To date, little information has been generated regarding
consumption of rebaudioside A alone (also referred to by the com-
mon name of rebiana). Maki et al. (2008) showed that consump-
tion of 1000 mg/day of rebaudioside A for 16 weeks did not alter
blood pressure or glucose homeostasis in subjects with type 2 dia-
betes mellitus.
The present investigation was designed to examine the poten-
tial effects of 4 weeks of daily consumption of 1000 mg of rebau-
dioside A on blood pressure and heart rate (HR) in healthy men
and women with normal baseline blood pressure (<120 mmHg sys-
tolic blood pressure (SBP) and <80 mmHg diastolic blood pressure
(DBP) as defined in the Seventh Report on Prevention, Detection,
Evaluation and Treatment of High Blood Pressure; Chobanian
et al., 2003). The study was conducted as part of a clinical program
designed to address questions raised by the Joint FAO/WHO Expert
Committee on Food Additives (JECFA) pertaining to the potential
for pharmacological effects of steviol glycosides (JECFA, 2005).
2. Methods
2.1. Study conduct
This was a randomized, double-blind, placebo-controlled trial conducted at six
clinical research sites in the United States. It was performed under Good Clinical
Practice Guidelines, the Declaration of Helsinki (2000), and US 21 Code of Federal
Regulations (Part 50 – Protection of Human Subjects). An institutional review board
(Schulman Associates Institutional Review Board, Inc., Cincinnati, OH) approved the
protocol before the initiation of the study. All subjects provided informed consent
and authorization for release of protected health information to the investigators
before protocol-specific procedures were carried out.
2.2. Subjects
Participants included healthy men and women, 18–74 years of age, with normal
blood pressure (defined as <120 mmHg SBP and <80 mmHg DBP; Chobanian et al.,
2003) who were not taking antihypertensive medications. Subjects were instructed
to maintain their habitual diet and physical activity patterns throughout the study.
A two-week single-blind placebo lead-in period was utilized to evaluate subject
compliance. To be eligible for randomization, subjects were required to be at least
80% compliant with placebo capsules during the lead-in.
Individuals with body mass index (BMI) P35.0 kg/m
2
were excluded from par-
ticipation as were those with a history or clinical evidence of significant cardiovas-
cular, gastrointestinal, renal, pulmonary, hepatic, or biliary disease. Additionally,
volunteers with fasting blood glucose P126 mg/dL or diagnosed diabetes mellitus
(type 1 or 2) were excluded as were women who were pregnant, lactating, planning
to be pregnant during the study, or those of childbearing potential who were not
using an approved method of contraception. Subjects who were smokers could
not have been planning to change smoking habits during the study period.
2.3. Treatments
Following the placebo lead-in, subjects were randomly assigned to receive four
250 mg capsules/day of either rebaudioside A (97% purity; rebiana, the common
name for rebaudioside A) or placebo (microcrystalline cellulose) for the four-week
double-blind treatment period. Two capsules were taken with the first meal of the
day and two with the evening meal. Compliance was assessed by capsule count and
subject interview. Percent compliance was calculated as 100 the number of doses
consumed/the expected number of doses. Following an overnight fast of 10–14 h,
subjects came to the clinic at weekly intervals during the double-blind period for
hemodynamic testing. They were instructed to abstain from vigorous physical
activity for at least 12 h prior to each clinic visit, and no tobacco products were al-
lowed for a minimum of 1 h prior to the visits.
2.4. Hemodynamic measurements
2.4.1. Resting
Resting, seated blood pressures were assessed at every clinic visit (weeks 2,
1, 0, 1, 2, 3, and 4) using an automated blood pressure device (Welch Allyn
Ò
Model
3500, Skaneateles Falls, NY). Measurements were taken at 0, 2, 4, 6, 8, and 10 min.
Blood pressure declines with seated rest and the rate of decline lessens over time
(Sala et al., 2006). To reduce the variability in the point estimate for seated, resting
blood pressure, the first two measurements were discarded and the remaining four
were averaged. Each subject was assigned to a specific cuff and monitor for all mea-
surements. Differences between treatment groups in the changes from baseline
(average of weeks 1 and 0) to treatment (average of weeks 1, 2, 3, and 4) were cal-
culated for SBP, DBP, and mean arterial pressure (MAP). Mean arterial pressure was
calculated as DBP þ
1
3
ðSBP DBPÞ.
2.4.2. Meal tests
At weeks 0 and 4, supine (after lying for 5 min) and standing (after standing for
2 min) blood pressure and heart rate were measured before and for 2 h after con-
sumption of a standard breakfast meal with two 250 mg capsules of rebaudioside
A or placebo. At week 0, all subjects received placebo, and at week 4, subjects re-
ceived their randomly assigned treatment. The standard breakfast meal was an 8
fluid oz chocolate-flavored shake (250 kcal; Ensure
Ò
, Abbott Nutrition, Columbus,
OH) which was consumed over a 10 min period. Pre-meal blood pressure and HR
measurements were taken at t=5 min, where t= 0 was the start of the test meal.
Post-meal blood pressure and HR measurements were obtained at t= 30, 60, 90 and
120 min. These four values were averaged to determine the post-meal response.
The changes from pre-meal to post-meal at weeks 0 and 4 for supine and standing
SBP, DBP, MAP, and HR were calculated.
2.4.3. 24-h Ambulatory monitoring
At the completion of the meal tests at weeks 0 and 4, each subject was fitted
with an ambulatory blood pressure monitor (ABPM; SE-25S 24-h Ambulatory Blood
Pressure Monitoring System, Tiba Medical, Portland, OR), which automatically col-
lected data every 30 min for 24 h. Subjects were asked to complete a diary during
this time to record their daytime activities, as well as the times for retiring and aris-
ing in the morning. Blood pressure monitoring data were considered inadequate if
P30% of the required data points were missing, there were gaps in data greater
than 2 h, or if the subject spent <6 h or >12 h from the time of retiring to the time
of arising (Hermida et al., 2005). Changes from week 0 to week 4 in morning, day-
time, nighttime, and 24-h SBP and DBP were calculated. Nighttime blood pressure
was defined as the average blood pressure recorded from the time the subject went
to bed until the time he/she got out of bed; morning blood pressure was defined as
the average during the first 2 h after arising; and daytime blood pressure was de-
fined as the average recorded during the remainder of the day.
2.5. Laboratory, diet, and physical activity measurements
Basic laboratory testing, including serum chemistry, hematology, and urinalysis,
was performed by Medpace Laboratories (Cincinnati, OH) at screening and follow-
ing treatment. Diet records were collected and analyzed at baseline and the end of
the treatment period using the Food Processor
Ò
Nutrition Analysis and Fitness Soft-
ware (version 8.6.0, Salem, OR). Physical activity was assessed with the Stanford 7-
day Physical Activity Questionnaire administered at weeks 0 and 4 (Sallis et al.,
1985).
2.6. Statistical analyses
The trial was designed to have at least 80% power to detect a 4.5 mmHg differ-
ence in resting, seated SBP response for rebaudioside A vs. placebo following
4 weeks of treatment, assuming a pooled standard deviation of 7.5 mmHg. Statisti-
cal analyses were generated using SAS version 9.1.3, service pack 4 (documentation
is available at http://support.sas.com/documentation/onlinedoc/91pdf/index_
913.html; SAS Institute, Cary, NC). All tests of statistical significance were com-
pleted at an
a
level of 0.05, two-tailed. Assumptions of normality of residuals were
investigated for each response variable using the Shapiro–Wilk test. If it was deter-
mined that the distribution could not be approximated by a normal curve (p for the
Shapiro–Wilk test 60.05), then values were ranked in ascending order (tied values
were given a mean rank) prior to running statistical models. Values throughout are
presented as mean ± standard error of the mean (SEM) unless otherwise specified.
Baseline and safety data were evaluated for all subjects enrolled in the study
who received at least one dose of study product. Blood pressure and HR data were
analyzed for all subjects who received at least one dose of double-blind study prod-
uct and provided at least one post-randomization blood pressure data point. In
cases where an intermediate data point(s) was missing, the average of the two sur-
rounding values was used in its place. The value at the previous non-baseline visit
was carried forward to the subsequent visit, if no subsequent data point(s) were
available.
Changes from baseline in blood pressures and HR were analyzed by analysis of
covariance using SAS PROC GLM. The initial model for each variable included terms
for baseline (pre-treatment) value, treatment, site, and treatment by site interac-
tion. The model was reduced in a stepwise manner, eliminating terms with p-values
P0.10 until only terms with p< 0.10 or treatment remained in the model. A similar
procedure was followed for the blood pressure and heart rate changes from the pre-
meal value during each meal test except that the pre-meal value for that day was
used as the covariate rather than the pre-treatment value. Data for resting, seated
and 24-h blood pressure responses were also analyzed for pre-specified subgroups
split at the sex-specific median values for SBP in order to assess the effects of rebau-
dioside A in subjects with low-normal blood pressure.
K.C. Maki et al. / Food and Chemical Toxicology 46 (2008) S40–S46 S41

3. Results
3.1. Subjects characteristics
A total of 100 healthy subjects with normal blood pressure were
randomly assigned to receive either rebaudioside A 1000 mg/day
(n= 50) or placebo (n= 50). Two subjects (both in the placebo
group) did not complete the study. One was lost to follow-up in
week 3, and the other discontinued the study during the final week
of the treatment period due to a serious adverse event (gastroen-
teritis). The investigator judged this event to be unrelated to the
study product.
Baseline and demographic characteristics were not significantly
different between treatment groups (Table 1). Participants ranged
in age from 18 to 73 years of age and were predominantly females
of non-Hispanic white race/ethnicity. Body mass index was some-
what higher in the rebaudioside A group than in the placebo group
(25.7 vs. 24.3 kg/m
2
,p= 0.058). Mean study product compliance
was 99% in both groups, and all subjects were at least 80%
compliant.
3.2. Hemodynamic measurements
3.2.1. Resting, seated blood pressures and heart rate
Values for resting, seated SBP, the primary outcome variable,
indicated that there were no significant differences between the
rebaudioside A and placebo groups at baseline or during the treat-
ment period (Table 2). Values for resting, seated DBP and MAP
were also not significantly different between rebaudioside A and
placebo groups at baseline or in the changes from baseline to treat-
ment. In addition, there were no significant differences between
the rebaudioside A and placebo groups for SBP, DBP or MAP when
the changes from baseline to each visit (weeks 1, 2, 3, and 4) were
considered individually (data not shown).
3.2.2. Ambulatory blood pressures
Twenty-four hour ambulatory blood pressure monitoring of SBP
and DBP revealed no significant differences between rebaudioside
A and placebo treatment groups at week 0 or in the changes from
week 0 to week 4 for morning, daytime, nighttime, and overall con-
tinuous 24-h readings (Table 3).
3.2.3. Supine and standing hemodynamic responses during meal tests
Supine and standing values pre-meal and the changes from pre-
to post-meal for SBP, DBP, MAP, and HR during the meal tests at
weeks 0 and 4 are shown in Table 4. Supine and standing SBP
and DBP values are shown in Figs. 1 and 2.
At week 0, there were no significant differences between groups
in pre-meal values or the changes from pre-meal to post-meal val-
ues for supine SBP, DBP, MAP and HR. This was also true for the
pre-meal measurements of these parameters at week 4.
The placebo group showed slight reductions in both supine SBP
and DBP (0.8 and 1.9 mmHg, respectively) compared to the pre-
meal value at week 4. In contrast, the rebaudioside A group
showed slight increases for the corresponding pre- to post-meal
changes (1.5 and 0.6 mmHg, respectively). No statistically signifi-
cant difference was present for SBP, while the differences in re-
sponse reached statistical significance for DBP (p= 0.045) and
Table 1
Baseline characteristics of all randomized subjects
Characteristic Rebaudioside A (n= 50) Placebo (n= 50) p-Value
n(%)
Male 12 (24.0) 9 (18.0) 0.461
Female 38 (76.0) 41 (82.0)
Race/ethnicity
Non-Hispanic white 40 (80.0) 38 (76.0) 0.641
a
African American 1 (2.0) 4 (8.0)
Hispanic 7 (14.0) 5 (10.0)
Asian 1 (2.0) 1 (2.0)
Other 1 (2.0) 2 (4.0)
Mean ± SEM
Age (year) 42.1 ± 1.9 41.0 ± 2.3 0.717
Body mass index (kg/m
2
) 25.7 ± 0.5 24.3 ± 0.5 0.058
Weight (kg) 71.1 ± 1.8 67.7 ± 1.7 0.168
Height (cm) 166.2 ± 1.4 166.6 ± 1.2 0.830
Abbreviation: SEM = standard error of the mean.
a
p= 0.629 for an additional comparison of Non-Hispanic white vs. all other race/
ethnicity categories.
Table 2
Changes from baseline to treatment for resting, seated blood pressure measurements
a
Resting, seated
measurements
Rebaudioside A
(n= 50)
Placebo
(n= 50)
p-Value
b
Mean ± SEM
Baseline SBP (mmHg) 110.0 ± 1.2 110.7 ± 1.3 0.683
SBP
D
(mmHg) 1.3 ± 0.7 0.4 ± 0.8 0.237
Baseline DBP (mmHg) 70.3 ± 0.9 71.2 ± 0.9 0.529
DBP
D
(mmHg) 1.3 ± 0.5 0.7 ± 0.5 0.154
c
Baseline MAP (mmHg) 83.6 ± 0.9 84.3 ± 1.0 0.554
MAP
D
(mmHg) 1.3 ± 0.6 0.6 ± 0.6 0.192
Abbreviations: DBP = diastolic blood pressure, MAP = mean arterial blood pressure,
SBP = systolic blood pressure, SEM = standard error of the mean.
a
Change (signified by
D
) represents the change from baseline (average of weeks
1 and 0) to treatment (average of weeks 1, 2, 3, and 4).
b
p-Values for the response variables are for the analysis of covariance with
baseline value as the covariate.
c
Values were ranked prior to analysis. Median values were similar to the means
shown.
Table 3
24-h Ambulatory blood pressure monitor readings at baseline (week 0) and the
change from baseline to week 4
a,b
Parameter Rebaudioside A Placebo p-Value
c
Mean ± SEM
Morning
Baseline SBP (mmHg) 111.7 ± 1.4 114.1 ± 2.0 0.336
d
Baseline DBP (mmHg) 68.3 ± 1.5 69.7 ± 1.5 0.732
d
SBP
D
(mmHg) 2.0 ± 2.0 2.8 ± 2.0 0.426
d
DBP
D
(mmHg) 1.0 ± 2.1 1.6 ± 1.8 0.392
d
Daytime
Baseline SBP (mmHg) 115.3 ± 1.6 117.1 ± 1.5 0.582
d
Baseline DBP (mmHg) 70.8 ± 1.2 70.9 ± 1.3 0.915
d
SBP
D
(mmHg) 1.2 ± 1.6 0.0 ± 1.7 0.833
d
DBP
D
(mmHg) 1.0 ± 1.8 2.4 ± 2.4 0.523
d
Nighttime
Baseline SBP (mmHg) 98.1 ± 1.0 99.7 ± 1.2 0.329
Baseline DBP (mmHg) 57.4 ± 0.9 57.6 ± 0.8 0.418
SBP
D
(mmHg) 1.7 ± 1.2 1.1 ± 1.2 0.638
d
DBP
D
(mmHg) 0.2 ± 0.9 0.1 ± 0.8 0.742
24-h
Baseline SBP (mmHg) 111.0 ± 1.1 110.7 ± 1.3 0.833
Baseline DBP (mmHg) 66.8 ± 1.0 65.8 ± 0.8 0.701
SBP
D
(mmHg) 0.1 ± 1.0 2.2 ± 1.0 0.277
d
DBP
D
(mmHg) 0.7 ± 0.9 1.6 ± 0.7 0.072
Abbreviations: DBP = diastolic blood pressure, SBP = systolic blood pressure,
SEM = standard error of the mean.
a
Morning blood pressure = average blood pressure during the first 2 h after
awakening; daytime blood pressure = average recorded during the rest of the day;
nighttime blood pressure = average recorded from the time the subject went to bed
until the time he/she got out of bed.
b
Change (signified by
D
) is the change from baseline (week 0) to week 4.
c
p-Values for the response variables are for the analysis of covariance with
baseline value as the covariate.
d
Indicates values were ranked prior to analysis. Median values were similar to
the means shown.
S42 K.C. Maki et al. / Food and Chemical Toxicology 46 (2008) S40–S46

MAP (p= 0.043). The supine HR response at week 4 did not differ
significantly between treatment groups.
At week 0, there were no significant differences between rebau-
dioside A and placebo groups in pre-meal or the changes from pre-
meal to post-meal values for standing SBP, DBP and MAP. Pre-meal
standing HR was significantly higher at week 0 in the placebo
group compared with the rebaudioside A group (78.9 vs.
74.7 bpm; p= 0.045), but the pre-meal to post-meal changes were
not significantly different between groups.
Pre-meal levels for standing DBP (74.7 vs. 72.4 mmHg;
p= 0.016), MAP (87.9 vs. 85.9 mmHg; p= 0.036) and HR (79.9 vs.
74.6 bpm; p= 0.020) were significantly higher in the placebo group
at week 4. Similar to the pattern observed for supine pressures, the
rebaudioside A group showed relative increases from pre-meal in
DBP (1.4 mmHg) and MAP (1.3 mmHg) that were significantly dif-
ferent from small declines in the placebo group (1.3 mmHg, p
<0.001 and 0.7 mmHg, p= 0.020, respectively). No significant dif-
ferences were observed for standing SBP or HR responses at week
4. Standing SBP (Fig. 2, Panel A) and DBP (Fig. 2, Panel B) at week 4
were also similar for rebaudioside A and placebo in the first 2 h fol-
lowing dosing.
3.3. Subgroup and sensitivity analyses
Pre-specified analyses conducted on data for resting, seated
and 24-h blood pressures for subgroups with baseline SBP split
at the sex-specific median (< and P108 mmHg for females and
< and P117 mmHg for males) are shown in Table 5 (below
the median) and Table 6 (above the median). In the lower base-
line SBP-subgroup, there was a small relative reduction from
baseline to treatment for rebaudioside A vs. placebo observed
for resting, seated MAP (0.3 vs. 1.5 mmHg, p= 0.036). Other-
wise, 24-h blood pressure responses in the two SBP-subgroups
did not differ significantly between rebaudioside A and placebo
treatment groups.
3.4. Body weight, diet, and physical activity
Baseline or changes from baseline in body weight did not differ
significantly between the rebaudioside A and placebo groups (data
not shown). Baseline values and changes from week 0 to week 4 in
intakes of total energy; percentages of energy from carbohydrate,
protein, fat, saturated fatty acids, poly- and monounsaturated fatty
acids, the ratio of polyunsaturated to saturated fatty acids, and
alcohol; dietary fiber; soluble dietary fiber; sodium; potassium;
calcium; and magnesium were not significantly different between
the rebaudioside A and placebo groups (data not shown). Baseline
values and changes from week 0 to week 4 in physical activity
were not significantly different between rebaudioside A and pla-
cebo treatments (data not shown).
3.5. Tolerance
Rebaudioside A was well tolerated. Sixteen subjects (32%) re-
ported adverse events in the rebaudioside A group compared to
18 subjects (36%) in the placebo group (p= 0.833). One serious ad-
verse event (gastroenteritis) was reported in the placebo group.
None of the adverse events were believed by the investigators to
be related to the study products. No signs or symptoms of hypoten-
sion (e.g., lightheadedness or dizziness) were reported in associa-
tion with rebaudioside A use. One subject in the rebaudioside A
group had a vagal response to a blood draw. Laboratory test results
(chemistry, hematology, and urinalysis) indicated no clinically
meaningful or statistically significant differences between the
rebaudioside A and placebo groups (Table 7).
4. Discussion
Several studies in the published literature have examined the
effects of steviol glycosides, primarily stevioside, on blood pressure
in animals and humans. A number of these have reported antihy-
Table 4
Supine and standing blood pressure and heart rate measurements during meal tests at weeks 0 and 4
Parameters Week 0 Week 4
Rebaudioside A
(n= 50)
Placebo
(n= 50)
p-Value Rebaudioside A
(n= 50)
Placebo
(n= 48)
p-Value
a
Mean ± SEM Mean ± SEM
Supine pre-meal
SBP (mmHg) 111.5 ± 1.5 109.7 ± 1.3 0.367 109.5 ± 1.2 111.5 ± 1.3 0.260
DBP (mmHg) 69.6 ± 1.1 68.9 ± 1.1 0.647 67.8 ± 1.0 69.9 ± 1.0 0.154
MAP (mmHg) 83.6 ± 1.1 82.5 ± 1.1 0.486 81.7 ± 1.0 83.7 ± 0.9 0.140
HR (bpm) 62.9 ± 1.5 66.1 ± 1.2 0.098 63.3 ± 1.5 67.0 ± 1.3 0.071
D
Post-meal
b,c
SBP (mmHg) 0.0 ± 0.9 0.9 ± 0.7 0.674 1.5 ± 1.0 0.8 ± 1.0 0.180
DBP (mmHg) 1.3 ± 0.6 1.2 ± 0.7 0.811 0.6 ± 0.6 1.9 ± 0.8 0.045
MAP (mmHg) 0.9 ± 0.6 0.5 ± 0.6 0.955 0.9 ± 0.7 1.5 ± 0.8 0.043
HR (bpm) 2.9 ± 1.0 4.5 ± 0.6 0.172
d
4.4 ± 0.7 2.8 ± 0.8 0.404
Standing pre-meal
SBP (mmHg) 115.1 ± 1.5 114.1 ± 1.3 0.595 112.8 ± 1.5 114.2 ± 1.1 0.163
d
DBP (mmHg) 75.0 ± 1.1 74.9 ± 1.2 0.931 72.4 ± 1.2 74.7 ± 1.5 0.016
d
MAP (mmHg) 88.4 ± 1.1 88.0 ± 1.1 0.773 85.9 ± 1.1 87.9 ± 1.1 0.036
d
HR (bpm) 74.7 ± 1.5 78.9 ± 1.4 0.045 74.6 ± 1.7 79.9 ± 1.5 0.020
D
Post-meal
b,c
SBP (mmHg) 0.8 ± 1.1 1.7 ± 0.9 0.645 1.1 ± 1.0 0.4 ± 0.9 0.745
DBP (mmHg) 0.5 ± 0.7 0.5 ± 0.9 0.907
d
1.4 ± 0.8 1.3 ± 1.2 <0.001
d
MAP (mmHg) 0.1 ± 0.7 0.2 ± 0.8 0.867 1.3 ± 0.7 0.7 ± 0.8 0.020
d
HR (bpm) 4.6 ± 0.8 3.7 ± 1.0 0.852 5.3 ± 1.1 1.9 ± 1.1 0.138
Abbreviations: DBP = diastolic blood pressure, HR = heart rate, MAP = mean arterial pressure, SBP = systolic blood pressure, SEM = standard error of the mean.
a
p-Values for the response variables are for the analysis of covariance with baseline value as the covariate.
b
Post-meal is the average of values collected at 30, 60, 90, and 120 min post-meal.
c
Change (signified by
D
) is the change from pre-meal to post-meal.
d
Values were ranked prior to analysis. Median values were similar to the means shown.
K.C. Maki et al. / Food and Chemical Toxicology 46 (2008) S40–S46 S43

pertensive properties (Chan et al., 1998, 2000; Hsieh et al., 2003;
Jeppesen et al., 2003; Liu et al., 2003; Dyrskog et al., 2005; Ferri
et al., 2006). Although results from some of the studies support a
blood pressure-lowering effect of stevioside (Chan et al., 1998,
2000; Hsieh et al., 2003; Jeppesen et al., 2003; Liu et al., 2003), par-
ticularly in individuals with elevated blood pressure, other, more
recently conducted studies in normotensive and hypertensive indi-
viduals have failed to support these findings (Ferri et al., 2006;
Geuns et al., 2007; Maki et al., 2008).
Investigations to address the effects of rebaudioside A on blood
pressure lowering are limited (Carakostas et al., 2008). In Goto-
Kakizaki rats, a model of type 2 diabetes, 8 weeks of daily ingestion
of rebaudioside A had no effect on blood pressure (Dyrskog et al.,
2005). In a study designed to investigate the effects of chronic con-
sumption of rebaudioside A on glucose homeostasis in subjects
with type 2 diabetes mellitus, Maki et al. (2008) showed that con-
sumption of 1000 mg/day of rebaudioside A for 16 weeks did not
significantly alter blood pressure. This finding corroborates the re-
sults of the current trial in a separate sample of men and women
with diabetes mellitus, more than half of whom were taking anti-
hypertensive medications.
The purpose of the current trial was to assess the potential
hemodynamic effects of rebaudioside A in individuals with normal
and low-normal blood pressures, in order to address specific ques-
tions raised by JECFA at their 63rd meeting about potential adverse
effects of steviol glycosides in this population. Subjects were en-
rolled in the study who met the criteria for normal blood pressure
(<120 mmHg SBP and <80 mmHg DBP). Furthermore, specific sta-
tistical evaluation of the subgroup of subjects with baseline SBP
below the sex-specific median was pre-specified to assess effects
in subjects with low-normal blood pressures (baseline SBP
<108 mmHg for females and <117 mmHg for males). This analysis
was included in order to address the JECFA question regarding po-
tential effects in asymptomatic hypotensive individuals. Asymp-
tomatic hypotensive individuals are relatively rare and thus
extremely difficult to identify for the purposes of a clinical study.
According to data from the National Health and Nutrition Examina-
tion Survey (NHANES), mean values for Americans aged 40–59 are
124 mmHg and 75 mmHg for SBP and DBP, respectively (Ong et al.,
2007). Therefore, the lower SBP-subgroup included individuals
whose values were well below the US population average.
The present study was designed to provide 80% power to detect
a 4.5 mmHg difference in SBP response for rebaudioside A vs. pla-
cebo with
a
= 0.05, two-tailed. In fact, the study had >90% power
due to lower than anticipated subject variability, which increased
the sensitivity to detect minor changes in blood pressure. The sub-
jects were also considered to be fully compliant with study product
consumption, based upon 100% of individuals enrolled consuming
>80% of the expected doses of study product during the treatment
period.
90
100
110
120
130
030
60 90 120
03060 90 120
Minutes Post-dose
Systolic Blood Pressure ( mm Hg)
50
60
70
80
90
Minutes Post-dose
Diastolic Blood Pressure (mm Hg)
Rebaudioside A
Placebo
Rebaudioside A
Placebo
Panel A
Panel B
Fig. 1. Supine systolic blood pressure (Panel A – top) and supine diastolic blood
pressure (Panel B – bottom) at pre-dose (0 min) and 30, 60, 90, and 120 min after
dosing with rebaudioside A or placebo at week 4.
90
100
110
120
130
03060
90 120
03060
90 120
Minutes Post-dose
Systolic Blood Pressure (mm Hg)
Rebaudioside A
Placebo
Rebaudioside A
Placebo
50
60
70
80
90
Minutes Post-dose
Dias tolic Blood Pressure (m m Hg)
Panel A
Panel B
Fig. 2. Standing systolic blood pressure (Panel A – top) and standing diastolic blood
pressure (Panel B – bottom) at pre-dose (0 min) and 30, 60, 90, and 120 min after
dosing with rebaudioside A or placebo at week 4.
S44 K.C. Maki et al. / Food and Chemical Toxicology 46 (2008) S40–S46

An intake of 1000 mg/day represents more than 10 times the
mean predicted intake of rebaudioside A for consumers of the
sweetener, and approximately 4 times the mean predicted daily in-
take for high-intake consumers (Renwick, 2008). No statistically
significant difference was observed between the rebaudioside A
and placebo groups for resting, seated SBP, the primary outcome
variable. Likewise, no statistically significant differences were
noted for SBP in any of the secondary outcome variables.
There were no statistically significant differences in pre-meal
supine blood pressure measurements at weeks 0 or 4, while pre-
meal standing DBP and MAP, but not SBP, at week 4 were lower
in the rebaudioside A group. However, because there were a large
number of statistical comparisons made for the secondary and sub-
group analyses, some statistically significant differences would be
expected to occur by chance. Nonetheless, the mean differences
between the rebaudioside A and placebo groups in DBP from the
secondary analyses, despite being statistically significant, were
small (<3 mmHg) and raised no safety concerns. In addition, sub-
jects reported no signs or symptoms suggesting intolerance.
The meal challenge was conducted to assess acute effects (up to
120 min post-dose) of rebaudioside A on blood pressure. However,
results from a subsequent pharmacokinetic study conducted in hu-
mans (Wheeler et al., 2008) indicate that if there were any effects
of rebaudioside A on blood pressure, these would unlikely be
apparent until several hours after consumption. Steviol glucuro-
nide, the principal metabolite for steviol glycosides, did not appear
in the blood until approximately 4–5 h post-dose and reached
maximum concentrations at 12 h. Therefore, based upon peak plas-
ma concentrations of the principal metabolite it would be expected
that subjects in the rebaudioside A treatment group would have
had circulatory levels of steviol glucuronide at the time of the meal
tolerance test at week 4 from the previous day’s consumption, but
these levels would not have been expected to increase post-dose
during the meal challenge period.
To the authors’ knowledge, steviol glycosides have not been
reported to cause elevations in blood pressure. Therefore, it is
notable that the supine and standing post-meal DBPs in the
rebaudioside A group increased relative to placebo at week 4,
although all differences were small (<3 mmHg). Examination of
Table 5
Changes from baseline to treatment for blood pressure measurements in the
subgroup of subjects with baseline systolic blood pressure below the sex-specific
median
a,b
Parameters Rebaudioside A (n= 28) Placebo (n= 20) p-Value
c
Mean ± SEM
Resting, seated measurements
Baseline SBP (mmHg) 104.4 ± 0.8 103.1 ± 1.7 0.444
SBP
D
(mmHg) 0.3 ± 0.8 2.4 ± 0.8 0.114
Baseline DBP (mmHg) 67.2 ± 0.9 67.2 ± 1.6 0.970
DBP
D
(mmHg) 0.5 ± 0.5 1.1 ± 0.7 0.091
d
Baseline MAP (mmHg) 79.6 ± 0.7 79.1 ± 1.5 0.752
MAP
D
(mmHg) 0.3 ± 0.6 1.5 ± 0.6 0.036
24-h measurements
Baseline SBP (mmHg) 108.5 ± 1.2 107.1 ± 1.9 0.504
SBP
D
(mmHg) 0.5 ± 1.5 1.6 ± 1.6 0.798
d
Baseline DBP (mmHg) 66.2 ± 1.1 65.3 ± 1.3 0.618
DBP
D
(mmHg) 1.5 ± 0.9 0.0 ± 1.0 0.347
Abbreviations: DBP = diastolic blood pressure, MAP = mean arterial pressure,
SBP = systolic blood pressure, SEM = standard error of the mean.
a
Median baseline SBP <108 mmHg for women and <117 mmHg for male.
b
Change (signified by
D
) in resting, seated measurements represents the change
from baseline (average of weeks 1 and 0) to treatment (average of weeks 1, 2, 3,
and 4), and
D
in 24-h measurements represents the change from baseline (week 0)
to week 4.
c
p-Values for the response variables are for the analysis of covariance with
baseline value as the covariate.
d
Values were ranked prior to analysis. Median values were similar to the means
shown.
Table 6
Changes from baseline to treatment for blood pressure measurements in the
subgroup of subjects with baseline systolic blood pressure above the sex-specific
median
a,b
Parameters Rebaudioside A (n= 22) Placebo (n= 30) p-Value
c
Mean ± SEM
Resting, seated measurements
Baseline SBP (mmHg) 117.0 ± 1.4 115.7 ± 1.0 0.870
d
SBP
D
(mmHg) 3.2 ± 1.2 2.2 ± 1.1 0.716
Baseline DBP (mmHg) 74.3 ± 1.5 73.9 ± 0.9 0.437
d
DBP
D
(mmHg) 2.3 ± 1.0 1.8 ± 0.7 0.395
d
Baseline MAP (mmHg) 88.6 ± 1.3 87.8 ± 0.7 0.476
d
MAP
D
(mmHg) 2.6 ± 1.0 2.0 ± 0.7 0.699
24-h measurements
Baseline SBP (mmHg) 114.2 ± 1.8 113.1 ± 1.6 0.661
SBP
D
(mmHg) 1.0 ± 1.4 2.6 ± 1.2 0.368
d
Baseline DBP (mmHg) 67.7 ± 1.7 66.1 ± 1.0 0.362
DBP
D
(mmHg) 0.4 ± 1.8 2.8 ± 1.0 0.291
Abbreviations: DBP = diastolic blood pressure, MAP = mean arterial pressure,
SBP = systolic blood pressure, SEM = standard error of the mean.
a
Median baseline SBP P108 mmHg for women and P117 mmHg for male.
b
Change (signified by
D
) in resting, seated measurements represents the change
from baseline (average of weeks 1 and 0) to treatment (average of weeks 1, 2, 3,
and 4); and
D
in 24-h measurements represents the change from baseline (week 0)
to week 4.
c
p-Values for the response variables are for the analysis of covariance with
baseline value as the covariate.
d
Values were ranked prior to analysis. Median values were similar to the means
shown.
Table 7
Serum chemistry and hematology parameters at screening (week 1) and the
changes from screening to week 4
a
Parameter Rebaudioside A
(n= 50)
Placebo
(n= 50)
p-Value
Mean ± SEM
Screening alanine transaminase (U/L) 22.0 ± 1.5 19.9 ± 1.1 0.264
Alanine transaminase
D
(U/L) 1.0 ± 0.9 0.6 ± 1.4 0.331
Screening aspartate transaminase (U/L) 22.6 ± 1.0 20.9 ± 0.8 0.180
Aspartate transaminase
D
(U/L) 0.9 ± 0.7 0.1 ± 0.7 0.288
Screening alkaline phosphatase (U/L) 65.2 ± 2.7 65.9 ± 2.3 0.830
Alkaline phosphatase
D
(U/L) 0.8 ± 0.8 0.0 ± 0.9 0.476
Screening blood urea nitrogen (mg/dL) 13.7 ± 0.6 14.5 ± 0.6 0.306
Blood urea nitrogen
D
(mg/dL) 0.1 ± 0.4 0.8 ± 0.4 0.141
Screening creatinine (mg/dL) 0.8 ± 0.0 0.8 ± 0.0 1.000
Creatinine
D
(mg/dL) 0.0 ± 0.0 0.0 ± 0.0 0.155
Screening gamma glutamyl
transferase (U/L)
20.1 ± 1.7 17.7 ± 1.5 0.278
Gamma glutamyl transferase
D
(U/L) 0.7 ± 0.7 0.6 ± 0.7 0.162
Screening red blood cell count (10
6
/
l
L) 4.4 ± 0.1 4.4 ± 0.1 0.669
Red blood cell count
D
(10
6
/
l
L) 0.0 ± 0.0 0.0 ± 0.0 0.201
Screening white blood
cell count (10
3
/
l
L)
6.0 ± 0.2 6.3 ± 0.2 0.356
White blood cell count
D
(10
3
/
l
L) 0.3 ± 0.2 0.2 ± 0.2 0.884
Screening basophil (%)
b
0.51 ± 0.06 0.47 ± 0.07 0.655
Basophil
D
(%) 0.09 ± 0.07 0.05 ± 0.10 0.741
Screening hemoglobin (g/dL) 13.3 ± 0.2 13.6 ± 0.2 0.292
Hemoglobin
D
(g/dL) 0.0 ± 0.1 0.1 ± 0.1 0.396
Screening hematocrit (%) 39.8 ± 0.5 40.8 ± 0.4 0.124
Hematocrit
D
(%) 0.3 ± 0.3 0.2 ± 0.3 0.192
SEM = standard error of the mean.
a
Change from baseline to week 4 is indicated by
D
.
b
Basophil (%) is presented because it was the only subset of white blood cells
that showed a significant difference between rebaudioside A and placebo in another
study (Maki et al., 2008).
K.C. Maki et al. / Food and Chemical Toxicology 46 (2008) S40–S46 S45

the values during the post-meal period showed that the DBPs in
the placebo and rebaudioside A groups were nearly identical. The
rises in the post-meal supine and standing DBPs in the rebaudio-
side A group were attributable to slightly lower pre-meal values,
thus were not indicative of a hypertensive effect of acute rebaudio-
side A consumption.
In 2004, following a review of the available safety data for stev-
iol glycosides, JECFA set a temporary acceptable daily intake limit
of 0–2 mg/kg body weight (JECFA, 2005). The Committee assigned
a temporary acceptable daily intake on the basis that there were
some indications that stevioside, a steviol glycoside, may have
blood pressure-lowering effects in subjects with hypertension. As
a result, JECFA requested additional data/information regarding
the potential effects of steviol glycosides in individuals with low
blood pressure.
The present trial had sufficient statistical power to detect mod-
est effects on blood pressure (>90% power to detect a 4.5 mmHg
difference in SBP) and showed that 1000 mg/day of rebaudioside
A administered over a 4-week period was well tolerated and had
no significant effect on most blood pressure values measured,
including resting, seated SBP, the primary outcome variable. Small
(<3 mmHg), but statistically significant changes in DBP and MAP
were noted in some secondary analyses, but were not considered
clinically meaningful from a safety perspective. Therefore, the re-
sults of the current study indicate that approximately 4 times
the estimated mean daily intake of rebaudioside A by high-intake
consumers (Renwick, 2008) was well tolerated and had no clini-
cally important impact on blood pressure in men and women with
normal and low-normal resting blood pressures.
Conflict of interest statement
Authors Tarka and Bisognano received financial support from
Cargill for consulting services.
Acknowledgement
The authors gratefully acknowledge Ashley Roberts, PhD for
assistance with the design and interpretation of the study results;
and Rachel Hubacher for technical assistance.
References
Carakostas, M.C., Curry, L.L., Boileau, A.C., Brusick, D.J., 2008. Overview: the history,
technical function and safety of rebaudioside A, a naturally occurring steviol
glycoside, for use in food and beverages. Food Chem. Toxicol. 46/7S, S1–S10.
Chan, P., Xu, D.Y., Liu, J.C., Chen, Y.J., Tomlinson, B., Huang, W.P., Cheng, J.T., 1998.
The effect of stevioside on blood pressure and plasma catecholamines in
spontaneously hypertensive rats. Life Sci. 63, 1679–1684.
Chan, P., Tomlinson, B., Chen, Y.J., Liu, J.C., Hsieh, M.H., Cheng, J.T., 2000. A double-
blind placebo-controlled study of the effectiveness and tolerability of oral
stevioside in human hypertension. Br. J. Clin. Pharmacol. 50, 215–220.
Chobanian, A.V., Bakris, G.L., Black H.R., Cushman, W.C., Green, L.A., Izzo Jr., J.L.,
Jones, D.W., Materson, B.J., Oparil, S., Wright Jr., J.T., Roccella, E.J., National Heart,
Lung, and Blood Institute Joint National Committee on Prevention, Detection,
Evaluation, and Treatment of High Blood Pressure, National High Blood Pressure
Education Program Coordinating Committee, 2003. The Seventh Report of the
Joint National Committee on Prevention, Detection, Evaluation, and Treatment
of High Blood Pressure: the JNC 7 report, JAMA, vol. 289, pp. 2560–2571.
Dyrskog, S.E.U., Jeppesen, P.B., Chen, J., Christensen, L.P., Hermansen, K., 2005. The
diterpene glycoside, rebaudioside A, does not improve glycemic control or affect
blood pressure after eight weeks treatment in the Goto-Kakizaki rat. Rev.
Diabetic Stud. 2, 84–91.
Ferri, L.A.F., Wilson, A.D.P., Yamada, S.S., Gazola, S., Batista, M.R., Bazotte, R.B., 2006.
Investigation of the antihypertensive effect of oral crude stevioside in patients
with mild essential hypertension. Phytother. Res. 20, 732–736.
Geuns, J.M.C., Buyse, J., Vankeirsbilck, A., Temme, E.H.M., 2007. Metabolism of
stevioside by healthy subjects. Exp. Biol. Med. 232, 164–173.
Hermida, R.C., Calvo, C., Ayala, D.E., Lopez, J.E., 2005. Decrease in urinary albumin
excretion associated with the normalization of nocturnal blood pressure in
hypertensive subjects. Hypertension 46, 960–968.
Hsieh, M.H., Chan, P., Sue, Y.M., Liu, J.C., Liang, T.H., Huang, T.Y., Tomlinson, B., Chow,
M.S.S., Kao, P.F., Chen, Y.J., 2003. Efficacy and tolerability of oral stevioside in
patients with mild essential hypertension: a two-year, randomized, placebo-
controlled study. Clin. Ther. 11, 2797–2808.
JECFA, 2005. Steviol glycosides. In: 63rd Meeting of the Joint FAO/WHO Expert
Committee on Food Additives, Geneva, Switzerland. World Health
Organization (WHO), Geneva, Switzerland, WHO Technical Report Series
928, pp. 34–39, 138.
Jeppesen, P.B., Gregersen, S., Rolfsen, S.E.D., Jepsen, M., Colombo, M., Agger, A., Xiao,
J., Kruhoffer, M., Orntoft, T., Hermansen, K., 2003. Antihyperglycemic and blood
pressure-reducing effects of stevioside in the diabetic Goto-Kakizaki rat.
Metabolism 52, 372–378.
Liu, J.C., Kao, P.K., Chan, P., Hsu, Y.H., Hou, C.C., Lien, G.S., Hsieh, M.H., Chen, Y.J.,
Cheng, J.T., 2003. Mechanism of the antihypertensive effect of stevioside in
anesthetized dogs. Pharmacology 67, 14–20.
Maki, K.C., Curry, L.L., Reeves, M.S., Toth, P.D., McKenney, J.M., Farmer, M.V.,
Schwartz, S.L., Lubin, B.C., Boileau, A.C., Dicklin, M.R., Carakostas, M.C., Tarka,
S.M., 2008. Chronic consumption of rebaudioside A, a steviol glycoside, in men
and women with type 2 diabetes mellitus. Food Chem. Toxicol. 46/7S, S47–S53.
Melis, M.S., 1992a. Renal excretion of stevioside in rats. J. Nat. Prod. 55, 688–690.
Melis, M.S., 1992b. Influence of calcium on the blood pressure and renal effects of
stevioside. Braz. J. Med. Biol. Res. 25, 943–949.
Melis, M.S., Sainati, A.R., 1991a. Participation of prostaglandins in the effect of
stevioside on rat renal function and arterial pressure. Braz. J. Med. Biol. Res. 24,
1269–1276.
Melis, M.S., Sainati, A.R., 1991b. Effect of calcium and verapamil on renal function of
rats during treatment with stevioside. J. Ethnopharmacol. 33, 257–262.
Ong, K.L., Cheung, B.M.Y., Man, Y.B., Lau, C.P., Lam, K.S.L., 2007. Prevalence,
awareness, treatment, and control of hypertension among United States adults
1999–2004. Hypertension 49, 69–75.
Renwick, A.G., 2008. The use of a sweetener substitution method to predict dietary
exposures for the intense sweetener rebaudioside A. Food Chem. Toxicol. 46/7S,
S61–S69.
Sala, C., Santin, E., Rescaldani, M., Magrini, F., 2006. How long shall the patient rest
before clinic blood pressure measurement? Am. J. Hypertens. 19, 713–717.
Sallis, J.F., Haskell, W.L., Wood, P.D., Fortmann, S.P., Rogers, T., Blair, S.N.,
Paffenbarger Jr., R.S., 1985. The physical activity assessment methodology in
the five-city project. Am. J. Epidemiol. 121, 91–106.
Wheeler, A., Boileau, A.C., Winkler, P.C., Compton, J.C., Prakash, I., Jiang, X.,
Mandarino, D.A., 2008. Pharmacokinetics of rebaudioside A and stevioside
after single oral doses in healthy men. Food Chem. Toxicol. 46/7S, S54–S60.
S46 K.C. Maki et al. / Food and Chemical Toxicology 46 (2008) S40–S46