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The aim of this study was to evaluate the effects of psyllium in type 2 diabetic patients. The study included three phases: phase 1 (1 week), phase 2 (treatment, 14 g fibre/day, 6 weeks) and phase 3 (4 weeks). At the end of each phase a clinical evaluation was performed after the ingestion of a test breakfast of 1824.2 kJ (436 kcal). Measurements included concentrations of blood glucose, insulin, fructosamine, GHbA(1c), C-peptide and 24 h urinary glucose excretion. In addition, uric acid, cholesterol and several mineral and vitamin concentrations were also evaluated. The study was performed at the Department of Pharmacology, Toxicology and Nursing at the University of León (Spain). Twenty type 2 diabetic patients (12 men and 8 women) participated in the study with a mean age of 67.4 y for men and 66 y for women. The mean body mass index of men was 28.2 kg/m(2) and that of women 25.9 kg/m(2). Glucose absorption decreased significantly in the presence of psyllium (12.2%); this reduction is not associated with an important change in insulin levels (5%). GHbA(1c), C-peptide and 24 h urinary glucose excretion decreased (3.8, 14.9 and 22.5%, respectively) during the treatment with fibre (no significant differences) as well as fructosamine (10.9%, significant differences). Psyllium also reduced total and LDL cholesterol (7.7 and 9.2%, respectively, significant differences), and uric acid (10%, significant difference). Minerals and vitamins did not show important changes, except sodium that increased significantly after psyllium administration. The results obtained indicate a beneficial therapeutic effect of psyllium (Plantaben) in the metabolic control of type 2 diabetics as well as in lowering the risk of coronary heart disease. We also conclude that consumption of this fibre does not adversely affect either mineral or vitamin A and E concentrations. Finally, for a greater effectiveness, psyllium treatment should be individually evaluated.
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ORIGINAL COMMUNICATION
Therapeutic effects of psyllium in type 2 diabetic
patients
M Sierra
1
*, JJ Garcı
´
a
1
, N Ferna
´
ndez
1
, MJ Diez
1
, AP Calle
1
and Farmafibra Group
{
1
Department of Pharmacology, Toxicology and Nursing, University of Leo
´
n, Leo
´
n, Spain
Objective: The aim of this study was to evaluate the effects of psyllium in type 2 diabetic patients.
Design: The study included three phases: phase 1 (1 week), phase 2 (treatment, 14 g fibre=day, 6 weeks) and phase 3 (4 weeks).
At the end of each phase a clinical evaluation was performed after the ingestion of a test breakfast of 1824.2 kJ (436 kcal).
Measurements included concentrations of blood glucose, insulin, fructosamine, GHbA
1c
, C-peptide and 24 h urinary glucose
excretion. In addition, uric acid, cholesterol and several mineral and vitamin concentrations were also evaluated.
Setting: The study was performed at the Department of Pharmacology, Toxicology and Nursing at the University of Leo
´
n
(Spain).
Subjects: Twenty type 2 diabetic patients (12 men and 8 women) participated in the study with a mean age of 67.4 y for men
and 66 y for women. The mean body mass index of men was 28.2 kg=m
2
and that of women 25.9 kg=m
2
.
Results: Glucose absorption decreased significantly in the presence of psyllium (12.2%); this reduction is not associated with an
important change in insulin levels (5%). GHbA
1c
, C-peptide and 24 h urinary glucose excretion decreased (3.8, 14.9 and 22.5%,
respectively) during the treatment with fibre (no significant differences) as well as fructosamine (10.9%, significant differences).
Psyllium also reduced total and LDL cholesterol (7.7 and 9.2%, respectively, significant differences), and uric acid (10%,
significant difference). Minerals and vitamins did not show important changes, except sodium that increased significantly after
psyllium administration.
Conclusions: The results obtained indicate a beneficial therapeutic effect of psyllium (Plantaben
1
) in the metabolic control of
type 2 diabetics as well as in lowering the risk of coronary heart disease. We also conclude that consumption of this fibre does
not adversely affect either mineral or vitamin A and E concentrations. Finally, for a greater effectiveness, psyllium treatment
should be individually evaluated.
European Journal of Clinical Nutrition
(2002) 56, 830 842. doi:10.1038=sj.ejcn.1601398
Keywords: type 2 diabetic patients; ispaghula husk; psyllium; dietary fibre; glucose; insulin; cholesterol; capillary blood glucose;
metabolic variables
Introduction
Dietary fibre has significant gastrointestinal effects and it is a
mainstay of treatment for constipation and haemorrhoids.
Insoluble fibre is most effective for the treatment of these
pathologies and an increased intake of soluble dietary fibre
appears to benefit patients with diabetes mellitus (Gray,
1995).
The advantages of high-fibre diets for diabetic patients
have been said to include lowering of serum lipids, assisted
weight reduction and maintenance, and lowering of blood
glucose levels (Kiehm et al, 1976; Anderson 1985a, b).
It is especially the gel-forming, water-soluble dietary
fibre components such as guar gum, pectin and psyllium
that have beneficial effects on carbohydrate metabolism
(Jenkins et al, 1977; Chuang et al, 1992; Ellis et al, 1991;
Fairchild et al, 1996; Gatenby et al, 1996; Wursch &
Pi-Sunyer, 1997).
*Correspondence: M Sierra, Department of Pharmacology, Toxicology
and Nursing, University of Leo
´
n, Leo
´
n, Spain.
E-mail: dftmsv@unileon.es
Guarantors: Matilde Sierra and Juan J Garcı
´
a.
Contributors: MS was mainly responsible for all stages of the study,
including the study design, discussion and interpretation of results
and writing of the paper. JJG participated in the discussion and
interpretation of results and in the statistical analysis. NF and MJD
were involved in the literature searches and data collection and entry
and assisted with the preparation of the paper. APC carried out the
analytical determinations and diet control. The Farmafibra Group was
in charge of the medical management of subjects and sample
collection and preparation.
{
The Farmafibra Group is: Juan C A
´
lvarez, Demetrio Carriedo, Luis J
Castro, Mariano de la Torre, Ara
´
nzazu Gonza
´
lez, M Angeles Gonza
´
lez,
Vicente Mora
´
n, Carlos Prieto and Ana M Sahagu
´
n.
Received 20 June 2001; revised 24 October 2001;
accepted 3 December 2001
European Journal of Clinical Nutrition (2002) 56, 830–842
ß 2002 Nature Publishing Group All rights reserved 0954–3007/02 $25.00
www.nature.com/ejcn
Psyllium or ispaghula husk (the husk of the seeds of
Plantago ovata) is a mixture of neutral and acid polysacchar-
ides with a rest of galacturonic acid. The polysaccharides are
built up from the monomers
D-xylose and L-arabinose, and
ispaghula husk contains 67% pentosanes. Ispaghula husk is a
gel-forming (water-soluble) bre which has been used in
treatment for constipation for many years. During the last
two decades, several studies have been carried out to inves-
tigate whether ispaghula interferes with normal intestinal
absorption of carbohydrate in healthy volunteers (Jarjis et al,
1984; Sierra et al, 2001) and in type 1 (Florholmen et al,
1982; Uribe et al, 1985) and type 2 diabetic patients (Sartor
et al, 1981; Jarjis et al, 1984; Pastors et al, 1991). The effect
of psyllium on fasting plasma cholesterol in hypercholester-
olaemic patients has also been evaluated (Bell et al, 1989)
and in obese and diabetic patients (Frati-Munari et al, 1983).
The results obtained in these studies indicate that, in gen-
eral, ispaghula administration yields to a decrease in glycae-
mia, insulinaemia and cholesterolaemia, but Jarjis et al,
(1984) failed to detect signicant glucose blunting.
In the present study we have evaluated the therapeutic
effect of psyllium on glycaemic control in type 2 diabetic
patients treated with glibenclamide and under dietary reg-
ulations. The effect on the total serum cholesterol concen-
trations and the distribution of serum cholesterol between
the high-density-lipoprotein (HDL) and the low-density-
lipoprotein (LDL) was also established. In addition, several
hepatic, renal and haematological parameters were evalu-
ated.
Subjects and methods
Patients
Twenty type 2 diabetic patients (12 men and 8 women)
participated in the study. The mean age of the men was
67.4 y (range 50 80 y) and that of the women 66 y (range
54 79 y). The mean body mass index (BMI) of men was
28.2 kg=m
2
(range 25 29.6 kg=m
2
) and of women 25.9 kg=m
2
(range 20 29.8 kg=m
2
).
The duration of diabetes in all the volunteers eligible for
the study was between 2 and 30 y (mean 10.4 y) in men and
between 2 and 18 y (mean 7 y) in women. Diabetes was
treated in all patients with a sulphonylurea (glibenclamide)
and by conventional dietary restrictions. The diet followed
by the volunteers was the same for all of them during the
study. This diet is recommended to diabetic patients by the
Program of INSALUD (National Institute of Health) and
contains 55% of carbohydrate, 30% of fat (10% of saturated
fat), 15% of protein and 25 g of bre per day.
All subjects were questioned to assess subjective gastro-
intestinal side effects of the bre, if any, but not one of the
patients communicated any adverse effect. Each subject had
normal stool consistence and frequency. Four patients who
suffered from constipation showed a clear improvement
during the treatment with bre. All the volunteers success-
fully completed the study.
Study design
The study was conducted on an outpatient basis. The volun-
teers had no history of gastrointestinal disease and other
major illnesses, and each subject served as his own control.
The protocol was approved by the Human Ethical Commit-
tee of the University and INSALUD of Le
´
on, Spain, and
performed in accordance with the principles of the Declara-
tion of Helsinki. Written informed consent was obtained
from each subject.
Patients were admitted to an open study for its entire
duration. The study protocol included three different phases
(phase 1, phase 2 (treatment) and phase 3) and at the end of
each phase, the therapeutic and dietary accomplishment
were evaluated by the patient and one of the investigators.
The study began with a 1 week period (phase 1) over
which subjects followed a diet for diabetes and received the
sulphonylurea. This was followed by the phase 2 (treatment
phase, 6 weeks) over which patients continued with the diet
and the sulphonylurea, and also received 3.5 g of psyllium
(one dose of Plantaben
1
, orange avoured, sugar-free,
Madaus, S.A., Spain) four times a day: before breakfast,
lunch, afternoon snack and dinner (14 g of psyllium=day).
Subjects were instructed to mix each bre packet in 250 ml of
water, followed by 50 ml water for glass cleaning, and to
drink the mixture before each meal. Phase 3 (4 weeks) was
carried out after a 2-week washout interval. As in the phase 1,
subjects followed the diet and received sulphonylurea.
During phases 1 and 3, the patients received the same
volume of water (300 ml) as in phase 2 without psyllium
before meals in order to avoid changes in gastric emptying.
A clinical examination was performed at the end of each
phase. On each occasion, and after overnight fast, they
ingested a standard breakfast (Ebeling et al, 1988) of
1824.2 kJ (436 kcal; 53% carbohydrate, 26% protein and
21% fat), which consisted of 80 g low-fat boiled ham, two
slices (60 g) of white bread and 200 ml low-fat milk with non-
sweetened black coffee. Before breakfast, one dose of the
bre was given.
Blood samples (7 ml) were drawn through a buttery
cannula placed in the forearm at 7 15, 0, 10, 20, 30, 45,
60, 75, 90 and 120 min after breakfast ingestion for blood
glucose estimation, and at 7 15, 0, 30, 60, 90 and 120 min
blood insulin concentrations were also determined. The
values calculated at 7 15 and 0 min were averaged to
obtain glucose and insulin fasting values.
Blood samples obtained at time 0 were also used to
determine several biochemical parameters (uric acid, total,
HDL and LDL cholesterol) as well as different minerals
(calcium, phosphorous, sodium, potassium, magnesium,
iron) and vitamins (A and E) whose blood levels can be
modied by the presence of bre. In addition, other para-
meters related to patient status were also determined: glyco-
sylated haemoglobin (GHbA
1c
), fructosamine and C-peptide
in serum as well as 24 h urinary glucose and C-peptide
excretion. The urine was collected from ingesting the test
breakfast until next morning.
Therapeutic effects of psyllium
M Sierra
et al
831
European Journal of Clinical Nutrition
Methods
Serum glucose was measured with the Schmidt method
(Schmidt, 1961) using an autoanalyser (Hitachi, mod. 704,
Tokyo, Japan). Insulin concentrations were determined with
an immunoradiometric assay (IRMA assay kit, Biosource
Europe, S.A., Nivelles, Belgium). Serum vitamin A and E
were determined by high-pressure liquid chromatography
(HPLC; Driskell et al, 1982). An enzymatic colorimetric
method was used for the determination of cholesterol (Boeh-
ringer-Mannheim, GmbH, Mannheim, Germany). The HDL
fraction was analysed after precipitation with magnesium
chloride and dextrane sulphate (Finley et al, 1978). LDL
cholesterol was calculated by the formula of Friedewald
et al (1972). GHbA
1c
was determined by commercial ion-
exchange chromatography (Quick-Step Fast Hemoglobin
System
1
, Isolab Inc., Akron, OH, USA). Minerals and uric
acid were determined by using an autoanalyser Hitachi,
model 704 (Tokyo, Japan). Serum fructosamine was analysed
in triplicate using the Cobas Fara II (Lloyd & Marples, 1984).
Urinary glucose concentrations were evaluated by using an
enzymatic method (Weatherburn & Logan, 1966). Finally, C-
peptide was determined by RIA (Kuzuya et al, 1976).
During the study, except the 2 week washout interval,
patients measured their diurnal blood glucose prole at
home twice a week (on Tuesday and on Thursday). On
these days six measurements were done (before and 90 min
after breakfast, lunch and dinner) using Glucostix
1
(Miles
Limited, Glamorgan, UK) test strips that were read with a
Glucometer (Miles Laboratories Inc., Elkhart, IN, USA). The
number of blood glucose determinations per patient was
132, during the three periods (12 in phase 1, 72 in phase 2,
48 in phase 3).
Statistical analysis
Arithmetic means and s.d.s were calculated from the results
measured. The data obtained from the three phases were
compared for statistical signicance by Friedmans test, at
P < 0.05 and, when the results were signicant, Wilcoxon
pairwise comparisons with Bonferroni correction were used,
except for capillary glycaemia, where Kruskal Wallis test
and Mann Whitney U-test were employed. All analyses
were performed by using the Statgraphics Plus for Windows
2.0 (Manugistic Inc., Rockville, MA, USA).
Results
Serum glucose
The extent of glucose absorption decreased in the presence
of psyllium when mean values were considered (Table 1 and
Figure 1). Differences in mean concentrations at different
sampling times were signicant, except when the values
obtained at time 0 for phases 2 and 3 were compared.
Signicant differences were also established for mean con-
centrations among subjects. C
max
decreased nearly 10% in
Table 1 Serum glucose concentrations (mmol=l) in 20 type 2 diabetic patients after a test breakfast
Phase 1 Phase 2 Phase 3
Time (min) x
¯
s.d. CV (%) x
¯
s.d. CV (%) x
¯
s.d. CV (%)
0
b
8.66 2.22
c
25.7 7.73 1.98 25.6 8.21 2.32 28.2
10
a,b
9.43 2.29
c
24.3 7.98 1.96 24.6 8.85 2.45
c
27.7
20
a,b
10.81 2.45
c
22.7 9.05 2.01 22.2 10.29 2.61
c
25.4
30
a,b
12.02 2.82
c
23.5 10.46 2.15 20.6 11.93 2.59
c
21.7
45
a,b
13.52 2.92
c
21.6 12.06 2.21 18.4 13.29 2.49
c
18.7
60
a,b
14.00 2.67
c
19.1 12.83 2.58 20.2 14.27 2.93
c
20.5
75
a,b
14.19 3.02
c
21.3 12.51 2.81 22.5 14.04 3.23
c
23.0
90
a,b
13.63 3.12
c
22.9 11.93 3.12 26.2 13.52 3.63
c
26.8
120
a,b
12.54 3.53
c
28.1 10.76 3.43 31.9 11.91 3.63
c
30.5
a
Signicant differences among phases (Friedmans test,
P
< 0.05).
b
Signicant differences among subjects (Friedmans test,
P
< 0.05).
c
Signicant differences with phase 2 (Wilcoxon modied test, for conditions see text).
Figure 1 Mean serum glucose concentrations in 20 type 2 diabetic
patients after test breakfast.
Therapeutic effects of psyllium
M Sierra
et al
832
European Journal of Clinical Nutrition
the phase 2 (treatment) curve when compared with the
values obtained in the phases 1 and 3. The rate of glucose
absorption was similar during phases 2 and 3 (t
max
¼ 60 min)
and less than in phase 1 (t
max
¼ 75 min).
The area under the serum glucose concentration time
curve (AUC) was 12.2% lower in the presence of bre than
that obtained at the end of phase 1 and 11.9% lower than
that obtained at the end of the phase 3 (signicant differ-
ences, Wilcoxons test).
When accumulated areas (AUC
t
, where t is the time over
which AUC has been calculated) were considered, signicant
differences were also found between phases 1 and 3 data
when compared with those obtained in the phase 2, except
at 10 min between phases 2 and 3 (Wilcoxons test).
Figure 2 (a) Individual serum glucose-time curves in 10 type 2 diabetic patients after test breakfast.
Therapeutic effects of psyllium
M Sierra
et al
833
European Journal of Clinical Nutrition
Large interindividual variations were observed in glu-
cose concentrations, with CV ranging from 18.7 to
31.9% (Table 1) and, because of this, it is important to
evaluate individual curves (Figure 2a and b) in addition
to mean curves (Figure 1). Thus, in 10 patients (numbers
1 10,Figure2a),glucoseconcentrationsandAUC
values were clearly lower at the end of the phase 2
than at the end of phases 1 and 3, with AUC decreases
Figure 2 (b) Individual serum glucose-time curves in 10 type 2 diabetic patients after test breakfast.
Therapeutic effects of psyllium
M Sierra
et al
834
European Journal of Clinical Nutrition
up to 34%. Five volunteers (numbers 11 15) showed
higher values during the phase 1 than during phases 2
and 3, and in three of them (numbers 11 13), the
curves obtained in phases 2 and 3 were very similar.
Finally, in ve subjects (numbers 16 20) the three
curves were very similar.
Serum insulin
AUC decreased a 5% in phase 2 in comparison with the value
obtained in phase 1, and it was 15% lower than in phase 3
(no signicant differences, Friedmans test, at P < 0.05).
Mean curve shapes (Figure 3) were similar in the three
phases.
The value of C
max
(Table 2) was lower in the presence of
bre (348.6 pmol=l) than in phases 1 (369.0 pmol=l) and 3
(394.8 pmol=l), but these differences were not signicant.
The individual insulinaemic responses were very differ-
ent, with CVs for the mean concentrations higher than those
obtained for glucose. In our opinion, this fact reects the
different states of type 2 diabetes evolution in which patients
can be. When phases 1 and 3 are compared, some patients
show a high decrease in AUC mean values (up to 47.6%),
while in others this value is scarcely modied or even
increases (up to 45% in one patient).
Examining the corresponding curves it can be observed
that nine patients showed low insulin concentration values.
Five of them had high glucose levels (numbers 3, 4, 10, 11
and 16), reaching concentrations over 16.7 mmol=l; in four
patients (numbers 9, 13, 14 and 20), the glucose concentra-
tions were high, with values greater than 13.3 mmol=l; in the
other volunteer (number 18), the glucose concentrations at
the end of the curve were over the basal levels. Five volun-
teers (numbers 1, 5, 7, 8 and 19) show high insulin concen-
Figure 3 Mean serum insulin concentrations in 20 type 2 diabetic patients after test breakfast.
Table 2 Serum insulin concentrations (pmol=l) in 20 type 2 diabetic patients after a test breakfast
Phase 1 Phase 2 Phase 3
Time (min) x
¯
s.d. CV (%) x
¯
s.d. CV (%) x
¯
s.d. CV (%)
0
a
85.6 46.3 54.0 85.1 50.4 59.3 97.2 40.0 41.1
30
a
211.7 126.6 59.8 186.5 90.9 48.8 201.8 110.2 54.6
60
a
332.3 225.7 67.9 327.0 199.3 61.0 386.3 255.1 66.0
90
a
369.1 277.4 75.2 348.7 217.0 62.2 395.0 289.6 73.3
120
a
257.0 203.3 79.1 250.8 187.6 74.8 304.4 225.1 73.9
Friedmanstest(
P
< 0.05).
a
Signicant differences among subjects. No signicant differences among phases were found.
Therapeutic effects of psyllium
M Sierra
et al
835
European Journal of Clinical Nutrition
trations during the administration of psyllium, and these
values were generally higher than in phase 1 and lower than
in phase 3. The three curves were similar in three patients
(numbers 2, 6 and 15), except in the last times in two of
them (numbers 2 and 6). Finally, in two subjects (numbers 12
and 17), the insulin concentrations decreased in the pre-
sence of bre, when compared with those obtained in phase
1, and were similar to the values shown in the phase 3 curve.
Capillary glycaemia
A total of 120, 678 and 441 values of postprandial glucose
concentrations were obtained, corresponding respectively to
phases 1, 2 (treatment) and 3 of the study. The same number
of preprandial data were evaluated. In general, there was a
good compliance, but one patient only measured the glucose
concentrations during phase 1; another patient forgot 2 days
during phase 2 and, nally, one patient failed one day during
phase 3.
Taking into account the mean values (Table 3), fasting
blood glucose was slightly lower (4.5%) during phases 2 and
3 than during phase 1 (no signicant differences, Kruskall
Wallis test, at P < 0.05). The mean preprandial values
corresponding to lunch and dinner were also slightly lower
and differences were not signicant (Kruskall Wallis test, at
P < 0.05).
Mean postprandial glucose levels decreased during phase
2: 10.2% vs phase 1 and 5.3% vs phase 3 (signicant differ-
ences, Mann Whitney U-test).
The mean postprandial glucose concentrations corre-
sponding to breakfast, lunch and dinner were always lower
during phase 2 than during phases 1 and 3. The decreases in
these values were 13.8% in breakfast, 7.8% in lunch and
8.2% in dinner (phase 2 vs phase 1), and 4.0% in breakfast,
6.7% in lunch and 4.4% in dinner (phase 2 vs phase 3).
Signicant differences were found between postprandial
capillary glycaemia obtained after breakfast between phases
1 and 2. Important interindividual variations were also
found in this parameter. In this way, some patients show
decreases for postprandial glycaemia close to 30%, while in
two subjects this parameter is scarcely modied.
Other parameters related to diabetes
Table 4 summarises several parameters related to diabetes.
The treatment with bre reduced slightly glycosylated hae-
moglobin (GHbA
1c
; 3.8% vs phase 1 and 5.5% vs phase 3),
although no signicant differences were observed. Similar
results were obtained with fructosamine (fell by 10.9% on
bre vs phase 1 and by 7.8% vs phase 3) and with blood C-
peptide (fell by 14.9% on bre vs phase 1 and by 10% vs
phase 3). The statistical evaluation showed signicant differ-
ences for fructosamine when we compared the value
Table 3 Capillary glycaemia (mmol=l) in 20 type 2 diabetic patients before and 90 min after meals
Phase 1 Phase 2 Phase 3
Time (min) x
¯
s.d. CV (%) x
¯
s.d. CV (%) x
¯
s.d. CV (%)
Before breakfast
b
7.72 1.90 24.61 7.34 1.88 25.59 7.46 1.88 25.16
After breakfast
a,b
11.58 3.31
c
28.59 9.98 2.81 28.16 10.39 3.13 30.14
Before lunch
b
7.27 2.64 36.24 6.69 2.49 37.20 6.68 2.33 34.86
After lunch
b
9.67 4.14 42.77 8.92 2.76 30.91 9.56 3.11 32.58
Before dinner
b
6.73 2.79 41.40 6.47 2.56 39.49 6.43 2.27 35.38
After dinner
b
10.02 3.28 32.74 9.20 2.60 28.21 9.63 2.83 29.35
a
Signicant differences among phases (Kruskall Walliss test,
P
< 0.05).
b
Signicant differences among subjects (Kruskall Walliss test,
P
< 0.05).
c
Signicant differences with phase 2 (Mann Whitney
U
-test, for conditions see text).
Table 4 Mean values ( s.d.) of different parameters related to diabetes measured in 20 type 2 diabetic patients
after a test breakfast
Phase 1 Phase 2 Phase 3
x
¯
s.d. CV (%) x
¯
s.d. CV (%) x
¯
s.d. CV (%)
Fructosamine (mmol=l)
a,b
3.0 0.9
c
29.6 2.7 0.7 25.3 2.9 0.7
c
22.4
Blood C-peptide (nmol=l)
b
0.91 0.44 48.6 0.78 0.34 43.8 0.86 0.40 45.9
Glycosylated HbA
1c
(%)
b
6.8 1.0 14.2 6.5 0.9 13.6 6.9 1.2 17.0
Urinary 24 h glucose excretion (mmol)
a,b
20.7 24.4 117.8 14.3 20.8 145.4 16.3 23.0
c
140.8
a
Signicant differences among phases (Friedmans test,
P
< 0.05).
b
Signicant differences among subjects (Friedmans test,
P
< 0.05).
c
Signicant differences with phase 2 (Wilcoxon modied test, for conditions see text).
Therapeutic effects of psyllium
M Sierra
et al
836
European Journal of Clinical Nutrition
obtained in phase 2 with those recorded in phases 1 and 3. In
these parameters important interindividual variations were
observed.
Twenty-four hour urinary glucose excretion was 22.5%
lower at the end of the treatment than in phase 1 and 14.6%
than in phase 3, however, signicant differences (Wilcoxons
test) were only found between the phases 2 and 3. In this
case, interindividual variations were even greater.
Other parameters
Serum total cholesterol concentrations decreased signicantly
under psyllium treatment by 7.7% and by 6.2% in comparison
Figure 4 (a) Individual serum insulin-time curves in 10 type 2 diabetic patients after test breakfast.
Therapeutic effects of psyllium
M Sierra
et al
837
European Journal of Clinical Nutrition
with phases 1 and 3, respectively. In the same way, LDL
cholesterol fell by 9.2 and 7.7%, respectively (signicant dif-
ferences, Wilcoxons test). HDL cholesterol remained
unchanged during phase 2 (no signicant differences, Fried-
mans test, at P < 0.05). Psyllium administration also reduced
uric acid (10%, signicant difference, Wilcoxons test).
Figure 4 (b) Individual serum insulin-time curves in 10 type 2 diabetic patients after test breakfast.
Therapeutic effects of psyllium
M Sierra
et al
838
European Journal of Clinical Nutrition
Finally, other variables, including potassium, calcium,
phosphorous, iron and vitamin A, showed no signicant
changes during the three phases (no signicant differences,
Friedmans test, at P < 0.05). An increase in the levels of
magnesium and vitamin E was found when data of phases
2 and 3 were compared (signicant differences, Wilcoxons
test). Sodium levels also showed an increase between phase 2
and phases 1 and 3 (signicant difference, Wilcoxons test).
Discussion
As indicated by other authors (MacMahon & Carless, 1998;
Rodrı
´
guez-Mora
´
n et al, 1998; Oliver, 2000), in this study
psyllium was well tolerated without any signicant adverse
effects.
The effects of sustained bre supplementation on glycae-
mic control in subjects with diabetes mellitus have been
examined with considerable variations in results. The data
are somewhat difcult to evaluate because of differences in
population, bre type, diet and study design (Weinstock &
Levine, 1988).
The effect of bre is related to its viscosity (Jenkins et al,
1978) and with the method of administration (Wolever et al,
1991).
Rendell (2000) indicates that improvement in glucose
tolerance produced by consumption of viscous bre is due
to slower absorption of carbohydrate rather than malabsorp-
tion. Intimate mixing, allowing physical interaction
between food and bre, seems to be important in converting
the carbohydrate to what might be termed a slow-release
form.
Wolever et al (1991) demonstrated in normal and in type
2 diabetic patients that psyllium reduced the glycaemic
response to a aked bran cereal test meal when the bre
supplement was sprinkled onto the top of the cereal or
incorporated into the akes, but not when it was taken
before the cereal. Despite this fact, in the present study the
bre was taken dispersed in water because psyllium incor-
poration in a meal (by sprinkling it) would make it, in most
cases, unpalatable, and because this is the usual way any
patient would prepare an oral treatment with a therapeutic
bre.
The mechanism of action of gel forming bre is related to
the ability to increase the viscosity of the gastrointestinal
contents and thus interfere with motility and absorption
(Hopman et al, 1988). Several authors (Holt et al, 1979;
Sandhu et al, 1987) have demonstrated an inhibitory effect
of dietary bre on gastric emptying, but others could not
prove it (Lawaetz et al, 1983; Lembcke et al, 1984). Hopman
et al (1988) showed that glucomannan affects absorption
within the intestine in a study carried out in patients with
previous gastric surgery, and this is in agreement with the
results obtained in several animal studies (Elsenhans et al,
1980,1981,1984; Johnson & Gee, 1981).
We found that psyllium, under the preparation used in
this study, decreased signicantly postprandial blood glucose
concentrations in type 2 diabetic patients. It appears that
this fact can show the best effect of psyllium. Earlier studies
reported that psyllium reduced fasting serum glucose con-
centrations in individuals with type 2 diabetes (Fagerberg,
1982) and in type 2 diabetic patients with chronic portal-
systemic encephalopathy (Uribe et al, 1985). Other studies
demonstrated that different preparations of ispaghula husk
lowered postprandial serum glucose concentrations in type 1
(Florholmen et al, 1982), in type 2 diabetic patients (Sartor
et al, 1981; Pastors et al, 1991; Anderson et al, 1999), in
healthy volunteers (Sierra et al, 2001) and in both healthy
and type 2 diabetic subjects (Jarjis et al, 1984). Fibre doses
used were different, ranging from 3.6 g administered with
breakfast (Florholmen et al, 1982) to 35 g per day adminis-
tered as a dietary supplement (Uribe et al, 1985). In contrast,
no signicant differences were found after a 50 g glucose load
Table 5 Minerals, vitamins and other biochemical parameters measured in 20 type 2 diabetic patients after a test
breakfast
Phase 1 Phase 2 Phase 3
x
¯
s.d. CV (%) x
¯
s.d. CV (%) x
¯
s.d. CV (%)
Uric acid (mmol=l)
a,b
0.33 0.08
c
24.2 0.30 0.07 24.7 0.33 0.07
c
22.4
Total cholesterol (mmol=l)
a,b
5.63 1.09
c
19.3 5.2 0.84 16.1 5.54 0.93
c
16.9
HDL cholesterol (mmol=l)
a,b
1.31 0.34 25.7 1.31 0.24 18.1 1.48 0.32
c
21.4
LDL cholesterol (mmol=l)
b
3.84 0.38
c
23.0 3.48 0.70 20.1 3.78 0.96 25.3
Ca (mmol=l)
b
2.38 0.10 4.4 2.34 0.11 4.5 2.35 0.08 3.4
P (mmol=l)
a,b
1.01 0.10 10.3 1.07 0.14 13.0 1.11 0.13 12.1
Na (mmol=l)
a,b
142.6 4.7
c
3.3 143.7 4.9 3.4 141.0 2.9
c
2.0
K (mmol=l)
a,b
4.6 0.4 9.1 4.4 0.4 9.2 4.3 0.4 8.6
Mg (mmol=l)
a,b
1.3 0.7 54.1 1.3 0.7 54.2 1.4 0.7
c
47.0
Fe (mmol=l)
b
15.2 4.14 27.2 15.0 3.94 26.3 16.9 5.28 31.3
Vitamin A (mmol=l)
b
2.44 0.35 21.5 2.09 0.70 26.9 2.79 0.72 27.0
Vitamin E (mmol=l)
a,b
36.7 9.98 27.2 39.2 9.13 23.3 44.3 9.12
c
20.6
a
Signicant differences among phases (Friedmans test,
P
< 0.05).
b
Signicant differences among subjects (Friedmans test,
P
< 0.05).
c
Signicant differences with phase 2 (Wilcoxon modied test, for conditions see text).
Therapeutic effects of psyllium
M Sierra
et al
839
European Journal of Clinical Nutrition
administered with 3.5 or 7 g bre to healthy subjects (Jarjis
et al, 1984).
The mean decrease of C
max
obtained in this study after the
administration of psyllium (10%) was similar to that
reported by Sartor et al (1981) after a standardized breakfast
(9%), and lower than the indicated by Pastors et al (1991) at
breakfast (14%) and at dinner (20%), and by Sierra et al
(2001) in healthy subjects after a glucose load (15.5%).
Results obtained with guar gum are variable. Several
authors report no modications in glycaemia or a modest
improvement of glycaemic control (Botha et al, 1981; Car-
roll et al, 1981; Lim et al, 1990; Stahl & Berger, 1990), while
others indicate signicant decreases (Smith & Holm, 1982;
Fuessl et al, 1987; Chuang et al, 1992; Fairchild et al, 1996;
Gatenby et al, 1996; Brenelli et al, 1997), some of them
similar to the value indicated in this paper (10.1%, Chuang
et al, 1992a, b) and others higher (50%, Fuessl et al, 1987;
35%, Brenelli et al, 1997).
In relation to insulin, the mean decrease we have found
when bre is administered is not signicant, although we
think that this may be due to the fact that patients had had
diabetes for different lengths of time. This result is similar to
that obtained by Jarjis et al (1984) in healthy and in type 2
diabetic volunteers. Pastors et al (1991) found signicant
decreases for insulin after the administration of psyllium in
type 2 diabetic patients, with a reduction (12%) higher than
the reported in this study (5%). We have also found in a
previous study (Sierra et al, 2001) carried out in healthy
volunteers, a signicant and higher reduction of insulin
concentrations (36.1%) after the administration of ispaghula
husk.
These differences observed in insulin concentrations after
the administration of psyllium, have also been reported with
guar gum: several authors found no signicant (Groop et al,
1986,1993) or minimum (Stahl & Berger, 1990) changes
while others indicate signicant differences (Chuang et al,
1992; Fairchild et al, 1996; Gatenby et al, 1996).
In relation to other parameters related to diabetes
(GhbA
1c
, fructosamine, C-peptide concentrations in blood
and in urine and glucose in urine), for all of them, we have
obtained a decrease in their concentrations in the presence
of bre, which was signicant for fructosamine. This last
fact is important because, due to the relatively short dura-
tion of this study, fructosamine is a better marker than
GhbA
1c
. This reduction might be due to psylliums ability
to reduce hunger feelings and energy intake (Rigaud et al,
1998). We have no data available from other authors about
how psyllium modies these parameters. The results
obtained with other soluble bres such as guar gum are
variable. Thus, Stahl and Berger (1990) found no signicant
differences in glycosilated haemoglobin after the adminis-
tration of 15 g of guar gum daily during 3 months; Jones
et al (1985), after the administration of 10 g=day during 2
months, obtained a signicant fall in GhbA
1c
levels, with-
out signicant changes in 24 h urinary glucose excretion.
Behall (1990) observed that guar gum signicantly reduced
blood C-peptide concentrations after the administration of
31.7 g bre per day during 6 months and Holman et al
(1987) obtained no signicant changes in blood C-peptide
and GhbA
1c
concentrations after the administration of
15 g=day during 8 weeks.
Mean reductions obtained in total and in LDL cholesterol
(7.7 and 9.2%, respectively, signicant differences) were
slightly higher than those showed by Bell et al (1989) in
hypercholesterolaemic patients (4.8% reduction in total cho-
lesterol level and 8.2% in LDL cholesterol) after a treatment
with 10.2 g psyllium daily during 12 weeks. The reduction
observed for LDL cholesterol by Davidson et al (1998) in
hypercholesterolaemic patients after being treated with
10.2 g psyllium per day during 24 weeks was also slightly
lower (5.3%) than our value. On the other hand, our results
were slightly lower than those found by Anderson et al (1999)
in men with type 2 diabetes and hypercholesterolaemia after 8
weeks receiving 10.2 g psyllium daily. Romero et al (1998)
observed that LDL cholesterol concentrations were reduced
by an average of 22.6 and 26% after administering 1.3 g=day of
psyllium to healthy volunteers. In the same way, other authors
(Rodrı
´
guez-Mora
´
n et al, 1998; Segawa et al, 1998) found a
signicant reduction in total and LDL cholesterol.
In relation to HDL cholesterol, we did not found signicant
changes in this parameter after the administration of bre.
Similar results were shown by other authors (Davidson et al,
1998; Romero et al, 1998). However, Rodrı
´
guez-Mora
´
n et al
(1998)observedasignicantincrease inthis parameterafterthe
administrationof 15 g psyllium dailytotype 2 diabeticpatients.
Results obtained with guar gum are, again, contradictory.
In this way, Jones et al (1985) found no changes in lipid
levels after the administration of this bre, while other
authors obtained signicant reductions in LDL cholesterol
concentrations without changes in HDL cholesterol
(Holamn et al, 1987) or with a signicant decrease in total
cholesterol (Blake et al, 1997).
It has been suggested that deciencies of calcium, iron,
trace metals, certain vitamins and possibly other nutrients
may occur after prolonged periods of high bre intake
(Nuttall, 1983; American Diabetes Association, 1987).
The slight decrease observed in the mean level of uric acid
at the end of the psyllium phase in relation to the other two
phases is signicant in both cases. We have no data obtained
by other authors for comparison and we think that further
studies are required in order to determine whether the use of
psyllium would be advantageous for the treatment of hyper-
uricaemic patients.
Results obtained in the present study on mineral and
vitamin levels indicate that psyllium does not signicantly
modify serum concentrations when mean phase 2 values
were compared with those obtained in phase 1, except that
sodium increases signicantly during the administration of
psyllium, although the differences in concentration are low.
We have no data available from other authors about how
psyllium modies these parameters. Chuang et al (1992)
found that sodium, potassium, chloride, magnesium and
Therapeutic effects of psyllium
M Sierra
et al
840
European Journal of Clinical Nutrition
calcium levels showed no signicant changes during the
treatment with guar gum (8 weeks).
Behall (1990) did not detect apparent changes in mineral
balance (calcium, magnesium, iron, copper and zinc), with
the exception of a negative manganese balance, after carbox-
ymethyl cellulose administration. In this study, carboxy-
methyl cellulose gum, karaya gum and locust bean gum
were consumed by the patients during 4 weeks each (19.5 g
of bre per day). The author, in a second study (Behall et al,
1989), administered 31.7 g guar gum per day during 6
months and found that mineral balance was not affected
for iron, copper, zinc, calcium, manganese or magnesium.
Taking into account the results obtained in the present
study, those found in an earlier study carried out in healthy
subjects (Sierra et al, 2001) and according to Chuang et al
(1992), we conclude that psyllium treatment effectiveness
should be evaluated individually in each subject with the
purpose of establishing the most adequate dose and admin-
istration regime and a greater efciency.
Acknowledgements
We wish to thank Madaus, S.A. Laboratory for the products
supplied and for their economic collaboration in this study,
the volunteers for their co-operation and Dr D Carriedo,
Head of Service of the Hospital de Leo
´
n, Dr JC Alvarez and
MA Gonzalez, members of the INSALUD Program for Dia-
betes Education and Control for their advice in the setting
up and execution of this study
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... This notion is furthered by the fact that TAG's were reduced to a greater extent in the combination group, benefiting from both the inulin and psyllium dependent mechanisms. Based upon this evidence the psyllium dependent effects likely stem from its gel forming capability which increases the viscosity of bowel contents, therefore delaying and reducing luminal carbohydrate absorption [30,35,36]. Conversely, inulin acts through non-absorption related mechanisms, potentially linked to its higher SCFA production or its impact upon bile acid metabolism. ...
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Refined foods are commonly depleted in certain bioactive components that are abundant in ‘natural’ (plant) foods. Identification and addition of these ‘missing’ bioactives in the diet is, therefore, necessary to counteract the deleterious impact of convenience food. In this study, multiomics approaches were employed to assess the addition of the popular supplementary soluble dietary fibers inulin and psyllium, both in isolation and in combination with a refined animal feed. A 16S rRNA sequencing and 1H NMR metabolomic investigation revealed that, whilst inulin mediated an increase in Bifidobacteria, psyllium elicited a broader microbial shift, with Parasutterella and Akkermansia being increased and Enterorhabdus and Odoribacter decreased. Interestingly, the combination diet benefited from both inulin and psyllium related microbial changes. Psyllium mediated microbial changes correlated with a reduction of glucose (R −0.67, −0.73, respectively, p < 0.05) and type 2 diabetes associated metabolites: 3-methyl-2-oxovaleric acid (R −0.72, −0.78, respectively, p < 0.05), and citrulline (R −0.77, −0.71, respectively, p < 0.05). This was in line with intestinal and hepatic carbohydrate response (e.g., Slc2a2, Slc2a5, Khk and Fbp1) and hepatic lipogenesis (e.g., Srebf1 and Fasn), which were significantly reduced under psyllium addition. Although established in the liver, the intestinal response associated with psyllium was absent in the combination diet, placing greater significance upon the established microbial, and subsequent metabolomic, shift. Our results therefore highlight the heterogeneity that exists between distinct dietary fibers in the context of carbohydrate uptake and metabolism, and supports psyllium containing combination diets, for their ability to negate the impact of a refined diet.
... Viscosity is a physicochemical characteristic which is associated with soluble dietary fiber contents like pectins, gums, and glucans. Viscosity and gel formation capacity is linked to soluble fiber's capacity of absorbing water and formation of gelatinous mass [14]. Soluble fiber forms gel and increases the viscosity of gastrointestinal tract contents. ...
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Dietary fiber is commonly known as roughage. Fibers are mostly present in vegetables, whole grain, nuts, legumes, and fruits. This is an indigestible part of the food obtained by plants. It includes polysaccharides such as cellulose, hemicellulose, pectic substances, mucilages, gums and lignin as well. Dietary fiber has beneficial physiological effect on health, so it is included in daily diet to decrease occurrence of several diseases. In this sequence, this chapter describes about the dietary fiber, psyllium commonly known as Isabgol which is prepared from the seed of the Plantago ovata Forsk (Psyllium ispaghula). Psyllium is hydrophilic mucilloid, has the capacity to absorb water and increases in volume while absorbing water. Psyllium consists of mixed viscous polysaccharide in which about 35% soluble and 65% insoluble polysaccharides (cellulose, hemicellulose, and lignin) are present. This can be used as gelling, food thickener, emulsifying and stabilizing agents in some food products. Psyllium is a natural biopolymer which has high quantity of hemicel-luloses consist of xylan backbone connected with arabinose, galacturonic acid and rhamnose units. Since last many years it is being used as therapeutic agent in several diseases like chronic constipation, inflammation of mucous membrane of GIT tract, duodenal ulcers, piles or diarrohoea etc. It may be source of renewable and biodegradable polymer.
... Several mechanisms may have explained the favorable body weight measurements associated with the intake of dietary fiber. For instance, dietary fiber consumption is linked with a delay in intestinal transit and helps modulate glucose and lipid oxidation, which are favorable for body weight regulation [20][21][22][51][52][53]. Further, dietary fibers prolong satiety and prevent excessive dietary energy intake [23,24]. ...
... 19 Psyllium is being widely used for the treatment of the gastric disorder, constipation, 20 diarrhea, 21 ulcerative colitis, 22 and hypercholesterolemia. 23 One of the most valuable uses of psyllium is noted in lowering the glucose concentration in type-2 diabetic patients. 24 Use of psyllium in lowering the cholesterol and low-density lipoprotein level in hypercholesterolemic adults signify its importance as a healthcare material as well. 25 Moreover, the prebiotic potential of psyllium has now been established in clinical trials. ...
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Herein, we report a polysaccharide-based hydrogel isolated from psyllium husk (a well-known dietary fiber) and evaluated for its swelling properties in deionized water (DW) at different physiological pH values, i.e., 1.2, 6.8 and 7.4. Swelling of psyllium hydrogel (PSH) in DW under the influence of temperature and at different concentrations of NaCl and KCl solutions was also examined. A pH-dependent swelling pattern of PSH was observed following the order DW > pH 7.4 > pH 6.8 > pH 1.2. Stimuli-responsive swelling and deswelling (on-off switching) behavior of PSH was observed in DW and ethanol, DW and normal saline, at pH 7.4 and pH 1.2 environments, respectively. Similar swelling behavior and on-off switching attribute of PSH-containing tablets indicated the unaltered nature of PSH even after compression. Scanning electron micrographs of swollen and then freeze-dried PSH via transverse and longitudinal cross-sections revealed hollow channels with an average pore size of 6 ± 2 μm. Furthermore, PSH concentration-dependent sustained release of theophylline from tablet formulation was witnessed for >15 h following the non-Fickian diffusion mechanism. Subacute toxicity studies revealed the non-toxic nature of PSH. Therefore, dietary fiber-based material, i.e., PSH could be a valuable pharmaceutical excipient for intelligent and targeted drug delivery.
... Although the mechanisms that underlie the inverse association between the CQI and the MetS in the present study are unknown, previous mechanistic studies have espoused various explanations on how the components of the CQI may affect the occurrence of MetS and its risk factors. For example, dietary fiber is associated with lower postprandial glucose levels and increased insulin sensitivity in diabetics and healthy subjects [59][60][61], thereby preventing the insulin resistance component of the MetS. Also, the results from clinical trials [62][63][64][65][66][67][68][69][70] and meta-analyses [71,72] support the cholesterolreducing effects and the prevention of hypertension and the improvements in the clinical features of MetS (glycemic control, lipoprotein profile, BMI, and blood pressure). ...
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Background Dietary carbohydrate quality may play an important role in disease development. We evaluated the association between carbohydrate quality index (CQI) and the odds of metabolic syndrome (MetS) in type 2 diabetes mellitus (T2DM) subjects in Ghana. Methods In this case-control study, we analyzed data using 124 T2DM subjects. We obtained dietary information using 2-day 24-h dietary recalls. We calculated CQI from dietary fiber, glycemic index, whole grains/total grains ratio, and solid carbohydrates/total carbohydrates ratio. Serum lipid profiles were measured after an overnight fast of 8–12 h. Results Upon adjustments for the effects of covariates, the CQI showed a positive association with high-density lipoprotein cholesterol concentration (beta coefficient (β) = 0.24; standard error (SE) = 0.20; P for trend = 0.01), and an inverse relationship with waist circumference (β = − 17.29; SE = 4.00; P for trend < 0.001), systolic blood pressure (β = − 15.74; SE = 4.69; P for trend < 0.001), diastolic blood pressure (β = − 7.23; SE = 2.97; P for trend = 0.02), and triglyceride concentrations (β = − 0.43; SE = 0.11; P for trend < 0.001). Overall, the CQI had an inverse relationship with the odds of MetS (Odds ratio tertile 3 vs.1 0.05; 95% Confidence interval: 0.01–0.23; p-trend < 0.001). Also, a positive correlation was found between the CQI and fiber, but the CQI showed a negative relationship with dietary glycemic index. Conclusions The present results suggest an inverse association between the CQI of a diet and the odds of MetS. The CQI approach of dietary recommendation may be a useful strategy for dietary carbohydrate selection for the prevention of MetS.
... The endogenous enzymes of the human digestive tract are unable to metabolize dietary fiber, which instead serves as the main energy source for bacteria in the colon (Hamaker & Tuncil, 2014). Soluble dietary fiber reduces the postprandial blood sugar and insulin responses (Sierra et al., 2002) and may have beneficial effects in protecting against several forms of cancer, reducing blood pressure, and exerting an anti-inflammatory effect in the digestive tract (Chawla & Patil, 2010) (Scheppach et al., 2004). Insoluble dietary fiber reduces the gastrointestinal transit time and increase the fecal bulk (Weickert et al., 2006). ...
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A dietary shift from resource-demanding animal protein to sustainable food sources, such as protein-rich beans, lowers the climate footprint of food production. In this study, we examined the nutrients and antinutrients in 15 fava bean varieties cultivated in Sweden to select varieties with high nutritional value. On a dry weight basis, the fava beans were analyzed for their content of protein (range 26 - 33%), amino acids (leucine range: 50.8 – 72.1 mg/g protein, lysine range: 44.8 – 74.8 mg/g protein), dietary fiber (soluble fraction range: 0.55 – 1.06 %, insoluble fraction range: 10.7 – 16.0 %), and iron (1.8 - 21.3 mg/100g) and zinc contents (0.9 - 5.2 mg/100g), as well as for the following antinutrients: lectin (0.8 - 3.2 HU/mg); trypsin inhibitor (1.2 - 23.1 TIU/mg) and saponin (18 - 109 µg/g); phytate (112 – 1,281 mg/100g); total phenolic content (1.4 – 5 mg GAE/g); and vicine(403 µg/g - 7,014 µg/g), convicine (35.5 µg/g - 3,121 µg/g) and the oligosaccharides raffinose (1.1–3.9 g/kg), stachyose (4.4 – 13.7 g/kg) and verbascose (8 – 15 g/kg). The results indicate substantial differences between cultivars in relation to their contents of nutrients and antinutrients. Only one of the cultivars studied (Sunrise) have adequate estimated bioavailability of iron, which is of major concern for a diet in which legumes and grains serve as important sources of iron. The nutritional gain from consuming fava beans is significantly affected by the cultivar chosen as the food source.
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The seeds and husk of Plantago origin are rich source of dietary fiber known for its medicinal use. Despite the use of both Plantago psyllium and Plantago ovata products due to their physicochemical and nutritional properties, only the effects of Plantago ovata husk have been studied. Their structure-forming properties may positively affect gluten-free bread quality only if an adequate dough hydration is used. The aim of the work is to analyze the effect of different Plantago products: Plantago psyllium seeds and Plantago ovata seeds and husk in quantities of 3, 6 and 9% share on the rheological profile of model gluten-free dough and bread and bread’s technological quality and shelf-life. The rheological parameters of the dough were determined with Mixolab protocols and uniaxial deformation test. Bread quality and its textural profile analysis after cooling and storage were determined. The addition of Plantago psyllium seeds weakened the dough. All additives contributed to a reduction in starch retrogradation, bread hardness and water loss during baking, and to the improvement of the doughs’ resistance to extension, dough energy and bread yield. This influence is strongest when the Plantago ovata husk was used. However, the consumer acceptance of the tested breads was low and, in this respect, the breads with the addition of seeds of both Plantago psyllium and ovata were considered to be better than the husk.
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Diabetic foot ulcers (DFUs) are a devastating ailment for many diabetic patients with increasing prevalence and morbidity. The complex pathophysiology of DFU wound environments has made finding effective treatments difficult. Standard wound care treatments have limited efficacy in healing these types of chronic wounds. Topical biomaterial gels have been developed to implement novel treatment approaches to improve therapeutic effects and are advantageous due to their ease of application, tunability, and ability to improve therapeutic release characteristics. Here, we provide an updated, comprehensive review of novel topical biomaterial gels developed for treating chronic DFUs. This review will examine preclinical data for topical gel treatments in diabetic animal models and clinical applications, focusing on gels with protein/peptides, drug, cellular, herbal/antioxidant, and nano/microparticle approaches. Statement of Significance : By 2050, 1 in 3 Americans will develop diabetes, and up to 34% of diabetic patients will develop a diabetic foot ulcer (DFU) in their lifetime. Current treatments for DFUs include debridement, infection control, maintaining a moist wound environment, and pressure offloading. Despite these interventions, a large number of DFUs fail to heal and are associated with a cost that exceeds $31 billion annually. Biomaterials have been developed to help target specific impairments associated with DFU with the goal to improve healing. A summary of these approaches is needed to help better understand the current state of the research.. This review summarizes recent research and advances in topical biomaterials treatments for DFUs.
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We describe a method for measuring high-density lipoprotein cholesterol. MgCl2 and dextran sulfate are used to precipitate all low-density and very-low-density lipoproteins. The supernate contains only high-density lipoproteins, the cholesterol concentration of which is estimated by an enzymic method, with a discrete analyzer (Abbott Bichromatic Analyzer). Concentration and instrument response are linearly related to 50 mg/liter. The precision of the method is excellent in the range of clinical interest (100 to 1000 mg of cholesterol per liter). The precision and efficiency of the precipitation are shown at various concentrations of high-density lipoprotein cholesterol. The method was compared to that of two laboratories in the Cooperative Lipoprotein Phenotyping Study group by testing a number of split samples, and agreement was good.
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This study of the effect of Metamucil in non-insulin-dependent diabetics revealed similar results as previously reported after the administration of other gel-forming fibres. Hitherto, studies have been made on the effect of LDL and HDL with diverging results. In this study, HDL was not significantly reduced after four months of treatment. Bran is probably relatively equal to the bulk laxatives in the treatment of constipation, but apparently bran lacks the effect on lipid and carbohydrate metabolism produced by the gel-forming fibres. Metamucil, being a mucilloid agent, in this study was proved to possess a significant long-acting reducing effect on fasting blood glucose and serum cholesterol.
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Data are presented which support recent recommendations that encourage an increase in dietary fiber for patients with diabetes mellitus. The addition of viscous fiber to the diabetic diet can improve postprandial glucose levels and cholesterol levels without serious adverse effects in many patients with normal gastrointestinal function. The possible mechanisms by which fiber supplementation enhance glucose tolerance in this population are unclear. Intestinal factors are thought to play an important role. Although a delay in gastric emptying has been documented by many investigators, this effect does not correlate with improved glycemic control. Hormonal responses to a meal are variably affected by fiber supplementation. Peripheral sensitivity to insulin may be enhanced. The efficacy of high-fiber diets in promoting weight reduction in obese patients with diabetes mellitus remains controversial.
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Psyllium hydrophilic mucilloid was examined for its ability to lower serum cholesterol levels in hypercholesterolemic patients. Seventy-five patients with mild to moderate hypercholesterolemia were evaluated in this randomized, double-blind, placebo-controlled parallel study. Patients were treated with a Step I diet for 12 weeks before receiving placebo or 3.4 g of psyllium (equivalent to 1 teaspoon) three times per day for 8 weeks. Compared with placebo, psyllium achieved an additional 4.8% reduction in total cholesterol level, 8.2% reduction in low-density lipoprotein cholesterol level, and 8.8% reduction in apolipoprotein B level. Psyllium did not significantly affect blood pressure or levels of high-density cholesterol, triglycerides, serum glucose, or iron. Reported adherence to diet and treatment was excellent, and no significant adverse side effects were noted. These results indicate psyllium hydrophilic mucilloid is an effective and well-tolerated adjunct to diet in the management of mild to moderate hypercholesterolemia. (JAMA. 1989;261:3419-3423)
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Twenty-eight mild hypercholesterolemic male and female adults were orally administered psyllium seed for 3 months. After psyllium treatment, the serum total cholesterol, low-density-lipoprotein-cholesterol and atherogenic index significantly decreased, but levels of high-density-lipoprotein-cholesterol, triglyceride and urea nitrogen did not. To determine the parameters associated with the cholesterol-lowering effect in the subjects' backgrounds, both biochemical and hematological parameters, we statistically examined the correlation between pretreatment parameters and the absolute change of total cholesterol level. The absolute change of total cholesterol level showed a direct correlation with the triglyceride level at pretreatment (r=0.41, P=0.03) and had an inverse correlation with urea nitrogen level (r=-0.46, P=0.01) but not with the total cholesterol level (r=-0.18). The change in urea nitrogen level had an inverse correlation with the urea nitrogen level itself at pretreatment (r=-0.82, P=7 x 10[-8]) and had a direct correlation with the triglyceride level (r=0.43, P=0.02). The change in triglyceride level had an inverse correlation with the urea nitrogen level (r=-0.48, P=0.008). Furthermore, the change in total cholesterol level had direct correlations with changes in the triglyceride level (r=0.56, P=0.002) and the urea nitrogen level (r=0.51, P=0.006), but these changes in triglyceride and urea nitrogen level did not correlate significantly. These findings suggest the close association of urea nitrogen and lipid metabolism in hyperlipidemia and psyllium seed treatment.
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To determine the part played by altered gastric emptying in the modification of glucose absorption by gel fibres, glucose tolerance tests were done in seven healthy volunteers with and without the addition of pectin to the ingested glucose solution and after pharmacological inhibition of gastric emptying with propantheline. Compared with the controls, pectin significantly reduced blood-glucose. Propantheline had a similar but more pronounced effect. Pectin and guar gum did not substantially alter glucose tolerance in a patient who had had total gastrectomy. In a further investigation, gastric emptying and paracetamol absorption were studied simultaneously in fourteen subjects. In eight of these the study was repeated after addition of guar gum and pectin to the ingested paracetamol. Both gastric emptying and paracetamol absorption were slower after gel fibre but the total absorption of the drug, reflected in urinary recovery, was not significantly reduced. The results suggest that the effects of guar gum and pectin on glucose tolerance and paracetamol absorption could be due simply to alteration in the rate of gastric emptying.