The Journal of Nutrition
Nutrition and Disease
Lifestyle Counseling and Supplementation with
Flaxseed or Walnuts Influence the Management
of Metabolic Syndrome1–4
Hongyu Wu,5An Pan,6Zhijie Yu,5Qibin Qi,5Ling Lu,5Geng Zhang,5Danxia Yu,5Geng Zong,5
Yunhua Zhou,5Xiafei Chen,7Lixin Tang,7Ying Feng,7Hong Zhou,8Xiaolei Chen,8Huaixing Li,5
Wendy Demark-Wahnefried,9Frank B. Hu,6,10,11* and Xu Lin5*
5Key Laboratory of Nutrition and Metabolism, Institute for Nutritional Sciences, Shanghai Institutes for Biological Sciences, Chinese
Academy of Sciences and Graduate School of the Chinese Academy of Sciences, Shanghai 200031, China;6Department of Nutrition,
Harvard School of Public Health, Boston, MA 02115;7Huadong Hospital, Fudan University, Shanghai 200444, China;8School Hospital,
Shanghai University, Shanghai 200040, China;9Department of Nutrition Sciences, University of Alabama, Birmingham, AL 35294-3360;
10Department of Epidemiology, Harvard School of Public Health, Boston, MA 02115; and11Channing Laboratory, Brigham and
Women’s Hospital and Harvard Medical School, Boston, MA 02115
A healthy lifestyle may ameliorate metabolic syndrome (MetS); however, it remains unclear if incorporating nuts or seeds into
lifestyle counseling (LC) has additional benefit. A 3-arm, randomized, controlled trial was conducted among 283 participants
screened for MetS using the updated National Cholesterol Education Program Adult Treatment Panel III criteria for Asian
Americans. Participants were assigned to a LC on the AHA guidelines, LC + flaxseed (30 g/d) (LCF), or LC + walnuts (30 g/d)
(LCF), and 216.0% (LCW). The reversion rate of MetS, i.e. those no longer meeting the MetS criteria at 12 wk, was not
significantly different among groups (LC group, 21.1%; LCF group, 26.6%; and LCW group, 25.5%). However, the reversion
(Apo) B, ApoE, and blood pressure) were significantly reduced from baseline in all 3 groups. However, the severity of MetS,
presented as the mean count of MetS components, was significantly reduced in the LCW group compared with the LC group
among participants with confirmed MetS at baseline (P = 0.045). Our results suggest that a low-intensity lifestyle education
program is effective in MetS management. Flaxseed and walnut supplementation may ameliorate central obesity. Further
studies with larger sample sizes and of longer duration are needed to examine the role of these foods in the prevention and
management of MetS.J. Nutr. 140: 1937–1942, 2010.
Metabolic syndrome (MetS),12a constellation of metabolic
abnormalities including central obesity, dyslipidemia, elevated
blood pressure, and hyperglycemia, is a well-established risk
factor for type 2 diabetes and cardiovascular disease (CVD) (1).
Owing to rapid transitions toward high energy intake and
sedentary lifestyle in last few decades, MetS has become a major
health challenge in China and affects ~15.1% (71 million
people) of Chinese adults according to the updated National
Cholesterol Education Program Adult Treatment Panel III
(NCEP ATP III) criteria for Asian Americans (2). Thus, it is
critical to establish strategies to prevent or control the epidemic
trend of MetS and its consequences.
Compelling evidence supports the role of diet in the devel-
opment of MetS (3). The scientific advisory committee of the
AHA has published dietary recommendations for MetS man-
agement (4). A decreased prevalence of MetS was reported with
1Supported by the Chinese Academy of Sciences (The Knowledge Innovation
Program, grant no. KSCX1-YW-02), the Chief Scientist Program of Shanghai
Institutes for Biological Sciences, Chinese Academy of Sciences (SIBS2008006),
the National Basic Research Program of China (973 Program, grant no.
2011CB504002), and the California Walnut Commission (Sacramento, CA),
who provided funding and donated walnuts. Pizzey’s Milling (Glanbia plc., North
America) donated the flaxseed.
2Author disclosures: H. Wu, A. Pan, Z. Yu, Q. Qi, L. Lu, G. Zhang, D. Yu, G. Zong, Y.
no conflicts of interest. Drs. Lin and Hu reported receiving research support from the
California Walnut Commission for conducting part of this study.
12Abbreviations used: ALA,a-linolenic acid; IQR, interquartilerange; LC, lifestyle
counseling; LCF, lifestyle counseling with 30 g/d of flaxseed supplementation;
LCW, lifestyle counseling with 30 g/d of walnuts supplementation; MetS,
metabolic syndrome; NCEP ATP III, National Cholesterol Education Program
Adult Treatment Panel III.
*To whom correspondence should be addressed. E-mail: email@example.com and
4Supplemental Figures 1 and 2 are available with the online posting of this paper
ã 2010 American Society for Nutrition.
Manuscript received May 18, 2010. Initial review completed June 10, 2010. Revision accepted August 11, 2010.
First published online September 8, 2010; doi:10.3945/jn.110.126300.
intensive approaches (5), i.e. very low-energy diets (6) and struc-
tured dietary regimens, including low-fat and high-carbohydrate
diets (7), and the Dietary Approaches to Stop Hypertension eat-
ing program (8). However, it is unknown whether a less intensive
lifestyle program might also be effective.
Flaxseed is a complex food containing high amounts of PUFA,
fiber, lignan precursors, and other substances that may have health
benefits (9). Similarly, walnuts are also a rich source of PUFA [both
(n-3) and (n-6) fatty acids] and contain several nonfat constituents,
such as plant protein (particularly arginine-rich proteins) and fiber.
Recently, 2 meta-analyses found that flaxseed and walnut inter-
ventions improved lipid profiles and reduced CVD risk (10,11).
However, the effects of these foods on MetS remain unclear.
Therefore, we conducted a 3-arm, randomized, controlled
clinical trial to investigate the effects of flaxseed and walnut supple-
mentation as an adjunct intervention to healthy lifestyle counseling
(LC) on the management of MetS in Chinese men and women.
In addition, we also evaluated the effects of all 3 interventions on
MetS components, especially central obesity, which is particularly
important for Chinese, who are known to have higher amounts of
abdominal adiposity with a given BMI, i.e. a metabolically obese
phenotype as compared with Europeans (12).
Study design and participants. The present study was a randomized
controlled trial. Participant screening was performed at 2 large univer-
sities in Shanghai by reviewing clinical records of annual physical
examinations conducted in 2008. MetS was defined by the updated
was also added as an additional inclusion criteria to reflect borderline
high LDL cholesterol level (13). Therefore, individuals were included
if they met at least 3 of the following criteria: 1) waist circumference
$ 90 cm for men or $ 80 cm for women (defined as central obesity);
2) triglycerides $ 1.7 mmol/L; 3) HDL cholesterol , 1.03 mmol/L
for men or , 1.30 mmol/L for women; 4) blood pressure $ 130/85 mm
Hg 5) fasting glucose $ 5.6 mmol/L; and 6) LDL cholesterol $ 3.4
mmol/L. Exclusion criteria were: 1) history of allergy or high consump-
tion of nuts, flaxseed, or sesame seeds (.120 g/wk); 2) clinically
diagnosed renal, liver, heart, pituitary, thyroid, or mental diseases, or
alimentary tract ulceration or diseases affecting absorption; 3) history of
CVD, cancer(s), or mental disorders; 4) current or previous (in the
preceding 6 mo) use of antidepressants, estrogen, or steroid therapy; and
5) pregnancy or lactation.
A total of 5845 university faculty and staff members were screened
for eligibility and 331 individuals responded to our recruitment
solicitations and were then invited to attend a screening visit, during
which time eligibility was verified (see CONSORT diagram, Supple-
mental Fig. 1). A total of 283 participants (158 men and 125 women)
were recruited. Based on the screening data, 239 patients had MetS and
44 had 2 components of MetS plus elevated LDL cholesterol. Partici-
pants were block randomized to 1 of the 3 intervention arms: 1) LC; 2)
LC with 30 g/d of flaxseed supplementation (LCF); or 3) LC with 30 g/d
of walnuts (LCW) supplementation. The study protocol was approved
by the Institutional Review Board of the Institute for Nutritional
Sciences and all participants provided written informed consent.
Intervention. All participants received counseling and written materials
based on the AHA guidelines, including a low-fat diet; limited con-
sumption of red or processed meat; decreasing salt intake to ,5 g/d;
increasing consumption of fruits, vegetables, and fish; smoking cessa-
tion; and, if they consumed alcohol, moderate consumption of wine was
encouraged (4). At the beginning of the intervention, participants
engaged in a 1-h group session with a registered dietitian and were
provided with guidance on maintaining their usual levels of energy
intake and physical activity.
Two isocaloric breads were provided for each participant every day.
The breads were similar except that 30 g of flaxseed or walnuts were
incorporated into the 100-g-weight bread for the LCF or LCW groups,
respectively. The 2 breads provided 1600–2100 kJ/d energy. All breads
were prepared in a single bakery under the supervision of 2 registered
dietitians. Quality control was conducted by random sampling and
weighing the breads weekly. Participants were instructed to substitute
the breads for part of the staple food such as rice and other wheat
products in their diet. It should be noted that the flaxseed and walnut
breads could be differentiated by their appearance and taste; therefore,
the participants were not necessarily unaware of the intervention arms.
However, researchers,dietitians, laboratorytechnicians,andstatisticians
were unaware of the group assignment.
Adherence to study protocol was ensured by asking participants to
return any unused bread that was then weighed. Compliance was
calculated as the weight of breads consumed divided by the prescribed
weight of total breads throughout the intervention. In addition, the ALA
content of erythrocyte membranes was used as a marker of adherence to
flaxseed and walnut breads.
Measurements. At baseline, we administered a short-form FFQ, a 3-d
food record, and a 32-item general questionnaire about education,
physical activity (International Physical Activity Questionnaire, short
7-d format), lifestyle, health status, history of disease, and medication
use. Standardized protocols were used to collect anthropometric mea-
sures. Body weight and height were measured in light indoor clothing
without shoes to the nearest 0.1 kg and 0.1 cm, respectively. BMI was
calculated as kg/m2. Waist circumference was obtained at the mid-point
between the lowest rib and the iliac crest to the nearest 0.1 cm, after
inhalation and exhalation and using nonstretch tape measures. Blood
pressure was measured on the right arm using an electronic blood
pressure monitor (Omron HEM- 705CP, OMRON Healthcare) with
participants in a comfortable seated position after at least a 5-min rest.
Participants were required to fast overnight and blood samples were
collected. Serum samples were stored at 2808C until laboratory
analyses. All examinations and sample collections were repeated at the
completion of the 12-wk intervention.
Serum glucose, total cholesterol, HDL cholesterol, LDL cholesterol,
triglycerides, and apolipoprotein (Apo) A-1, B, and E were measured
enzymatically on an automatic analyzer (Hitachi 7080) with reagents
purchased from Wako Pure Chemical Industries. Hemoglobin A1C
(HbA1c) was quantified from resolved erythrocyte with automated
immunoassay (Roche Diagnostics). Seruminsulin levelswere determined
by a sandwich ELISA (Linco Research). ALA levels in erythrocyte
membranes were measured by GC (14).
Statistical methods. The analyses were based on the intention-to-treat
principle. We used descriptive statistics with means and SD to charac-
terize the study participants. ANOVA and x2tests were used to compare
means of quantitative variables and qualitative traits, respectively.
Natural-logarithmic transformation was applied prior to analyses if
values had a skewed distribution (triglycerides and ApoE). Within- and
between-group differences were expressed as means (95% CI) or
medians [interquartile range (IQR)]. Within-group and between-group
differences were compared using paired Student’s t tests and ANOVA,
respectively. At 12 wk, we calculated the proportion of participants who
no longer met the criteria for MetS (i.e. reverted MetS). The severity of
MetS was presented by the mean number (count) of MetS components.
Subgroup analyses stratified by sex, baseline central obesity status,
baseline BMI, and weight change were also performed.Differences in the
reversion of MetS and its components were assessed by using logistic
regression analysis with the LC group set as the referent. Data were
analyzed using Stata (version 9.2) and P , 0.05 (2-sided) was considered
significant. Bonferroni’s correction was used to adjust for multiple
testing due to a large number of outcome variables.
A total of 277 (97.9%) of the 283 participants randomized
completed the 12-wk intervention. Participants dropped out due
1938Wu et al.
to intervention-unrelated health conditions, business issues, and
loss of interest (Supplemental Fig. 1).
Baseline characteristics. The age range was 25–65 y and
55.8% (n = 158) of the participants were men. After random-
ization, the 3 groups appeared fairly balanced with respect to
major demographic characteristics, medication uses, and meta-
bolic profiles. Based on the baseline survey, 179 participants
(63.3%) met the MetS criteria and 256 (90.5%) had at least
2 components of MetS (Table 1).
Dietary intake and physical activity levels. Based on the
weight ratio of consumed and prescribed breads, dietary
adherence was deemed excellent, with a mean adherence of
98.7%. At 12 wk, total energy intakes decreased from baseline
and in all groups (all P , 0.02 for within-group differences). The
percent of energy from protein increased in all groups (all P ,
0.002 for within-group differences). The percent of energy from
dietary fat increased, whereas that from carbohydrate decreased
in the LCF and LCW groups (all P , 0.006 for within-group
differences). The consumption of PUFA was higher in the LCF
and LCW groups (all P , 0.001 for between-group differences)
than in the LC group. Compared with the LC group, the LCF
and LCW groups consumed more dietary fiber and had greater
ALA levels in their erythrocyte membranes (P , 0.001 for both
between-group differences) (Table 2). Physical activity did not
change in any of the groups or differ from the LC group in the
LCF or LCW group (Table 2).
Changes in MetS status. The percentage of all participants
with MetS was ~46% at completion of the study, which was
lower than that at baseline (P , 0.05). The percentage of
individuals with MetS decreased from baseline by 16.9, 20.2,
and 16.0% in the LC, LCF, and LCW groups, respectively. The
percentage of participants with each MetS component also
decreased significantly from baseline. In addition, the reversion
rate of central obesity was higher in the LCF (19.2%; P = 0.008)
and LCW (16.0%; P = 0.04) groups than in the LC group (6.3%)
We observed no between-group differences in outcomes for
any subgroup analyses defined by sex, baseline central obesity
status, baseline BMI, or weight change, except that among
participants with central obesity at baseline, reversion of hyper-
glycemia was notable in the LCF group, with an odds ratio (95%
Characteristics of the randomized participants at baseline1
LC, n = 95 LCF, n = 94 LCW, n = 94P-value4
Men, n (%)
Current smokers, n (%)
Alcohol drinkers, n (%)
Medication, n (%)
Oral hypoglycemic agents
Aspirin and antiphlogiston agents
MetS (NCEP ATP III),2n (%)
MetS components, n (%)
Elevated fasting glucose2
Reduced HDL cholesterol2
Elevated blood pressure2
Waist circumference, cm
Systolic blood pressure, mm Hg
Diastolic blood pressure, mm Hg
Total cholesterol, mmol/L
LDL cholesterol, mmol/L
HDL cholesterol, mmol/L
48.6 6 8.0
48.5 6 8.0
48.2 6 8.4
25.4 6 2.4
25.1 6 2.3
25.7 6 2.9
70.6 6 10.9
89.7 6 7.6
133.7 6 14.6
85.4 6 9.0
6.3 6 1.4
5.7 6 0.5
6.1 6 1.7
4.3 6 1.4
1.4 6 0.5
1.54 6 0.38
1.15 6 0.32
52.4 6 34.1
69.7 6 9.4
88.7 6 6.2
133.0 6 17.1
85.6 6 11.6
6.3 6 1.8
5.7 6 0.9
6.0 6 1.5
4.2 6 1.3
1.4 6 0.4
1.53 6 0.35
1.10 6 0.30
47.1 6 28.0
72.2 6 11.4
90.0 6 7.8
135.0 6 16.2
86.5 6 9.9
6.1 6 1.3
5.7 6 0.7
5.8 6 1.4
4.1 6 1.2
1.3 6 0.4
1.47 6 0.31
1.08 6 0.27
47.5 6 24.4
1Data are mean 6 SD or n (%) unless otherwise indicated.
2n (%) of the participants who met the specific criteria.
3Data are medians (IQR) and were log-transformed for across group comparisons.
4P-value for comparison across groups.
Flaxseed, walnut, and metabolic syndrome 1939
CI) of 3.01 (1.10–7.54) for LCF compared with the LC group
after multivariate adjustment (Supplemental Fig. 2).
In addition, the severity of MetS, presented as the mean count
of MetS components, was lower in the LCW group compared
with the LC group (P = 0.045) among participants with con-
firmed MetS at baseline, although the 2 groups did not differ
after Bonferroni’s correction (Table 4).
Effects on MetS traits. Body weight decreased significantly in
all groups. Weight loss tended to be greater in the LCF group
(P = 0.10) compared with the LC group. Most of the other CVD
risk factors (waist circumference, serum glucose, total choles-
terol, LDL cholesterol, ApoB, ApoE, and blood pressure)
decreased significantly from baseline in all 3 groups (Table 4).
Because flaxseed supplementation has effects on central obe-
sity and hyperglycemia, we further performed a post hoc anal-
participants with central obesity at baseline (Fig. 1). Compared
with the LC group, serum glucose was lower in the LCF group,
with a between-group mean difference of 20.35 mmol/L
(95% CI, 20.69 to 20.01; P = 0.047). Moreover, flaxseed
supplementation also prevented an increase of HbA1c, with a
between-group mean difference of 20.10 (95% CI, 20.20 to
0.00; P = 0.05). Among LC and LCF participants without
central obesity at baseline, serum glucose also decreased during
the study (P , 0.001).
In this 3-arm, randomized controlled dietary intervention, a less-
intensive LC program was found to significantly decrease body
weight and CVD risk factors among Chinese participants with
clinically confirmed MetS or higher MetS risk. This also is one of
the first studies to document the comparative effects of flaxseed
and walnut supplementation in ameliorating central obesity as
well as the severity of MetS in this high risk population.
especially combined with dietary change, plays an important role
in controlling MetS (3,5,8,15–17), although many of these inter-
ventions were far more intensive than the regimens pursued in the
currentstudyand promotedsubstantiveweightlossorlarge shifts
in dietary patterns. In this study, all participants were instructed
to follow a general healthy lifestyle according to AHA guidelines.
After the 12-wk intervention, a 16.7% reduction of MetS was
observed, which suggests that a low-intensity LC program could
be useful for MetS management.
Flaxseed and walnuts are considered energy-dense foods due
to their high contents of PUFA. Interestingly, participants as-
signed to the 30 g/d flaxseed- or walnut-supplemented diets did
not gain weight, and participants in the LCF group showed a
tendency to lose more weight than those in the LC group.
Moreover, our data showed that LC plus flaxseed or walnuts
may have additional benefits on central adiposity compared with
LC only. Abdominal obesity is well recognized as a potential
Prevalence of MetS and its components among
LC, n = 95LCF, n = 94LCW, n = 94
MetS and its components
MetS (NCEP ATP III)
Elevated fasting glucose
Reduced HDL cholesterol
Elevated blood pressure
1Data are n (%).aDifferent from the LC group, P , 0.05.
2Reversion rate indicated the proportion of participants who met the criterion at
baseline but not at 12 wk.
Dietary intake and physical activity level of the
participants during the 12-wk intervention period1
Variable LC, n = 95 LCF, n = 94LCW, n = 94
Total energy intake, kJ/d
Energy from carbohydrates, %
Energy from protein, %
Energy from fat, %
Monounsaturated fatty acids, g/d
Dietary fiber, g/1000 kJ
Erythrocyte membrane ALA, % of total fatty acids
Change from baseline to 12 wk
10,341 6 268
8665 6 276a
9915 6 259
8740 6 263b
9873 6 238
9058 6 247b
51.3 6 0.7
49.9 6 0.7
51.5 6 0.8
46.6 6 0.8a, d
51.7 6 0.7
48.1 6 0.7a
14.3 6 0.2
15.3 6 0.2b
14.3 6 0.2
15.7 6 0.2a
13.8 6 0.2
15.1 6 0.2a
33.7 6 0.7
34.3 6 0.7
34.4 6 0.7
37.5 6 0.8b,c
34.0 6 0.6
36.5 6 0.7b,d
10.5 6 0.5
10.2 6 0.5
10.6 6 0.5
10.8 6 0.5
10.5 6 0.5
11.5 6 0.5d
13.4 6 0.7
17.9 6 0.7a
14.2 6 0.6
17.9 6 0.7a
14.3 6 0.6
17.5 6 0.6a
25.3 6 0.9
17.9 6 0.9a
26.6 6 1.1
32.3 6 1.6a,c
24.9 6 1.1
33.6 6 1.2a,c
22.6 6 0.8
16.7 6 0.8a
20.5 6 1.3
42.2 6 1.3a,c
20.5 6 1.3
33.9 6 1.3a,c
313 6 27
347 6 28
329 6 25
339 6 26
373 6 27
390 6 27
0.24 6 0.10
0.22 6 0.11
20.02 6 0.12
0.22 6 0.09
0.38 6 0.15
0.16 6 0.17a,c
0.22 6 0.10
0.27 6 0.11
0.04 6 0.10a,c
1Data are mean 6 SD. Letters indicate different from baseline (aP , 0.001;bP ,
0.05) or from LC (cP , 0.001;dP , 0.05).
2MET-min, minutes at a given metabolic equivalent level.
1940Wu et al.
etiologic factor of MetS (18); hence, reverted central obesity is
important for overall MetS management. This finding from our
study is particularly important for Asians, a population that is
likely to have metabolic obesity (12), even under normal weight
conditions, compared with Caucasians (19). However, the
mechanisms by which flaxseed and walnuts act in reverting
abdominal obesity remain unclear, although limited evidence
suggests that the abundance of PUFA in the diet might serve as
an important modulator for body fat deposition. In a small
clinical trial, Summers et al. (20) reported that changing from a
diet rich in SFA to one abundant in PUFA resulted in a 25%
reduction of abdominal fat without altering body weight. A
cross-sectional study also reported that a high dietary PUFA:SFA
ratio was inversely associated with waist circumference and
waist:hip ratio (21).
Another noteworthy finding is that among participants with
central obesity at baseline, flaxseed incorporation seemed to
decrease fasting glucose and prevent the increase of HbA1c. Few
studies have evaluated the effect of flaxseed on glucose metab-
olism. Nonetheless, administering flaxseed lignan in rodents was
shown to prevent and delay the development of diabetes (22).
Our previous intervention trial also showed that flaxseed lignan
improved glycemic control in type 2 diabetics patients (23).
Thus, consistent with these results, this study provides evidence
for the first time, to our knowledge, that flaxseed may have a
favorable impact on glycemic control in individuals with MetS
or at increased risk for MetS.
To our knowledge, this is the first randomized controlled trial
with a feeding component to evaluate the effects of lifestyle
education with and without supplementation of whole flaxseed
or walnuts among individuals with MetS. Our study, however,
has certain limitations. First, due to discrepancies in screening
between physicians and study staff, not all study participants
met the criteria for MetS, although the vast majority (91%) had
at least 2 components of MetS. Second, the relatively small
sample size limited our power to detect differences in many
metabolic endpoints, especially because our control group also
lost weight. It should be noted that in previous studies, the
control group received virtually no intervention and thus had a
greater likelihood of detecting between-group differences (8,24).
Finally, the duration of this intervention, although fairly typical
for diet interventions, may be too short to detect clinically
meaningful changes in metabolic disorders.
Differences in anthropometrics and serum biochemistry between the LCF or LCW group and the LC group and changes
within groups during the 12-wk intervention period1
Within-group differences Between-group differences
LC, n = 95LCF, n = 94LCW, n = 94LCF vs. LCLCW vs. LC
Waist circumference, cm
Systolic blood pressure, mm Hg
Diastolic blood pressure, mm Hg
Total cholesterol, mmol/L
LDL cholesterol, mmol/L
HDL cholesterol, mmol/L
20.82 (21.11 to 20.52)a
21.23 (21.82 to 20.63)a
27.0 (29.5 to 24.5)a
24.4 (25.8 to 23.1)a
0.06 (20.11 to 0.21)
20.44 (20.67 to 20.21)a
20.04 (20.50 to 0.33)
20.47 (20.73 to 20.20)a
20.37 (20.59 to 20.15)a
20.12 (20.19 to 20.05)a
20.09 (20.15 to 20.03)a
20.07 (20.11 to 20.02)a
20.05 (20.18 to 0.06)a
4.14 (28.52 to 16.9)
20.58 (20.79 to 20.37)a
21.18 (21.51 to 20.86)a
21.50 (22.09 to 20.91)a
28.8 (211.0 to 26.6)a
25.0 (26.3 to 23.7)a
20.01 (20.07 to 0.04)
20.57 (20.77 to 20.37)a
20.07 (20.50 to 0.32)
20.56 (20.82 to 20.29)a
20.44 (20.67 to 20.21)a
20.15 (20.20 to 20.09)a
20.13 (20.18 to 20.07)a
20.09 (20.14 to 20.04)a
20.05 (20.17 to 0.05)a
20.48 (26.54 to 5.58)
20.81 (21.08 to 20.53)a
20.92 (21.19 to 20.65)a
21.16 (21.72 to 20.61)a
28.2 (210.7 to 25.8)a
24.2 (25.7 to 22.7)a
0.05 (20.02 to 0.12)
20.40 (20.61 to 20.20)a
20.07 (20.52 to 0.36)
20.35 (20.59 to 20.10)a
20.27 (20.47 to 20.08)a
20.09 (20.15 to 20.03)a
20.07 (20.13 to 20.01)a
20.06 (20.11 to 20.02)a
20.04 (20.14 to 0.05)a
3.66 (21.32 to 8.70)
20.93 (21.21 to 20.65)a
20.37 (20.81 to 0.07)
20.27 (21.11 to 0.56)
21.77 (25.10 to 1.55)
20.57 (22.46 to 1.31)
20.07 (20.16 to 0.01)
20.13 (20.44 to 0.17)
20.02 (20.30 to 0.25)
20.09 (20.46 to 0.28)
20.07 (20.39 to 0.24)
20.03 (20.11 to 0.06)
20.04 (20.12 to 0.05)
20.02 (20.09 to 0.05)
0.01 (20.04 to 0.06)
24.68 (218.7 to 9.36)
20.23 (20.57 to 0.11)
20.10 (20.50 to 0.30)
0.06 (20.75 to 0.87)
21.22 (24.71 to 2.27)
20.23 (21.79 to 2.25)
20.01 (20.10 to 0.09)
0.03 (20.27 to 0.34)
20.02 (20.27 to 0.24)
0.12 (20.23 to 0.48)
0.10 (20.19 to 0.38)
0.03 (20.06 to 0.12)
0.02 (20.07 to 0.11)
0.01 (20.06 to 0.07)
0.02 (20.04 to 0.07)
20.48 (213.1 to 14.1)
20.35 (20.69 to 20.01)b
1Data are means (95% CI) unless otherwise indicated.aDifferent from baseline, P , 0.05;bDifferent from the LC group, P , 0.05.
2Data are medians (IQR) and were log-transformed for across group comparisons.
3Data from participants with MetS at baseline were analyzed [n = 64 (LC), n = 57 (LCF), and n = 58 (LCW)].
HbA1c (B) during the 12-wk intervention period in participants with
central obesity at baseline. Values are means (95% CI), n = 66 (LC), n =
70 (LCF), and n = 73 (LCW). * Different from LC group, P , 0.05.
Changes in the serum glucose concentration (A) and blood
Flaxseed, walnut, and metabolic syndrome 1941
In conclusion, our results suggest that a low-intensity LC Download full-text
program could be useful in MetS management. Although flax-
seed or walnut supplementation did not provide additional
benefits on blood lipids, incorporating these foods into diets may
improve central obesity status. Further studies with larger
sample sizes and of longer duration are needed to examine the
role of these foods in the prevention and management of MetS.
We thank Drs. Yiping Qiu and Zhiming Ye, Xichao Teng, Lili
Chen, and Xiaoqiang Fei from Huadong Hospital, Shanghai
University, and Donghua University for taking part in this study.
We also thank Liang Sun, Chen Liu, Jing Wang, Wei Gan,
Jingwen Zhu, Qianlu Jin, Shaojie Ma, and He Zheng in our
research group for their kind assistance at various stages of this
trial. H.W. conducted research, analyzed data, and wrote the
paper; A.P., Z.Y., Q.Q., H.L., and X.C. conducted research and
analyzed data; W. D-W. edited the paper; L.L., G.Z., D.Y.,
G.Z., and Y.Z. conducted research and collected data; L.T. and
Y.F. collected dietary intake data; H.Z. and X.C. recruited
participants and conducted research; and F.B.H. and X.L.
designed research and edited the paper. All authors read and
approved the final manuscript.
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