|
|
| |
|
Google AdSense
Google AdSense is for web publishers who want to make more revenue from advertising on their site while maintaining editorial quality...
|
|
|
|
|
|
|
 |
|
Dietary
factors influence the development of cardiovascular
disease (CVD). The diet of Alaskan Eskimos
differs from that of other populations.
We surveyed Eskimo adults in Northwest
Alaska to document their usual dietary
intakes, differences based on gender and
age, and sources of selected nutrients,
and to generate appropriate dietary advice
to reduce CVD. Interviewers surveyed 850
men and women 17-92 y old, using a quantitative
food-frequency instrument. We observed
many significant (chi(2) analysis P <
0.05) differences in nutrient intakes
among 3 age-groups. Energy intake from
carbohydrate was negatively related to
participant age-group (P < or = 0.01).
Energy intake from all fats (P < 0.001)
and polyunsaturated fat (P < or = 0.01)
was positively related to age-group among
both men and women in contrast to other
studies in which age differences were
either not observed or decreased with
age.
Native
foods were major sources of monounsaturated
and polyunsaturated fats, including 56%
of (n-3) fatty acids primarily from seal
oil and salmon. However, Native foods
contributed significantly less to the
diets of young adults than to those of
elders, especially among women. Store-bought
foods were the main sources of energy,
carbohydrate, fat, saturated fat, and
fiber for all adults. Based on their nutrient
density and potential to inhibit CVD,
continued consumption of traditional foods
is recommended. Variations in intake by
age may portend changing eating patterns
that will influence CVD as participants
age. These data will contribute to understanding
dietary risk factors for cardiovascular
disease in this population.
|
 |
|
|
Department
of Human Biology, University of Guelph,
Ontario, Canada. The average daily consumption
of seal oil by the Inuit people is approximately
8-9 g, yet there is very little information
on the effect of seal oil consumption
on cardiovascular disease risk factors.
In this study, 19 healthy, normocholesterolemic
subjects consumed 20 g of encapsulated
seal oil containing eicosapentaenoic acid
(EPA; 20:5n-3), docosahexaenoic acid (DHA;
22:6n-3), and docosapentaenoic acid (DPA;
22:5n-3) or 20 g of vegetable oil (control)
per day for 42 days. Levels of selected
cardiovascular and thrombotic risk factors
as well as fatty acid profiles of serum
phospholipid and nonesterified fatty acid
(NEFA) were determined.
EPA levels
in serum phospholipid and NEFA increased
by 4.3- and 2.7-fold, respectively, in
the seal oil supplemented group. DHA levels
rose 1.5- and 2.1-fold, respectively,
and DPA levels rose 0.5- and 0.7-fold,
respectively. Arachidonic acid (AA) levels
dropped by 26% in both serum phospholipid
and serum NEFA. There was a significant
decrease in the ratio of n-6 to n-3 fatty
acids in serum phospholipid from 7.2 to
2.1 and a significant increase in the
ratio of EPA/AA in NEFA. Ingestion of
seal oil raised the coagulant inhibitor,
protein C, values by 7% and decreased
plasma fibrinogen by 18%. No alterations
in other hemostatic variables, including
plasma activity of Factors VII, VIII,
IX, and X and antithrombin, or in the
concentrations of von Willebrand Factor,
total cholesterol, high-density lipoprotein
cholesterol, low-density lipoprotein cholesterol,
triglyceride, glucose, Apo A-1, or lipoprotein(a)
were observed in either group.
Other
risk factors for cardiovascular disease,
including hematocrit, white blood cell
count, plasma viscosity, systolic and
diastolic blood pressures, heart rate,
and platelet aggregation after stimulation
with ADP or collagen did not change. Our
results indicate that seal oil supplementation
in healthy, normocholesterolemic subjects
decreased the n-6/n-3 ratio and increased
EPA, DHA, and DPA and the ratio of EPA/AA
and DHA/AA in the serum phospholipid and
NEFA, while exhibiting a modest beneficial
effect on fibrinogen and protein C levels. |
|
|
|
The
influence of various dietary marine oils
and olive oil on fatty acid composition
of serum and platelets and effects on
platelets and serum lipids were investigated
as part of an extensive study of the effects
of these oils on parameters associated
with cardiovascular/thrombotic diseases.
Healthy volunteers (266) consumed 15 mL/d
of cod liver oil (CLO); whale blubber
oil (refined or unrefined); mixtures of
seal blubber oil and CLO; or olive oil/CLO
for 12 wk. In the CLO, seal oil/CLO, and
whale oil groups, serum levels of eicosapentaenoic
acid (EPA) were increased. In platelets,
EPA was increased in the CLO, seal/CLO,
and olive oil/CLO groups. The localization
of n-3 polyunsaturated fatty acids in
the triacylglycerols did not seem to influence
their absorption.
Intake
of oleic acid is poorly reflected in serum
and platelets. No significant differences
in triacylglycerols (TG), total cholesterol,
or high density lipoprotein cholesterol
were observed, even though TG were reduced
in the CLO, CLO/seal oil, and whale oil
groups. Mean platelet volume increased
significantly in both whale oil groups
and the CLO/olive oil group. Platelet
count was significantly reduced in the
refined whale oil group only. Lipopolysaccharide-stimulated
blood tended to generate less thromboxane
B2 in CLO, CLO/seal, and CLO/olive groups.
The whale oils tended to reduce in vivo
release of beta-thromboglobulin. In conclusion,
intake of various marine oils causes changes
in platelet membranes that are favorably
antithrombotic. The combination of CLO
and olive oil may produce better effects
than these oils given separately. The
changes in platelet function are directly
associated with alterations of fatty acid
composition in platelet membranes.
|
|
|
|
We
examined whether dietary supplementation
with seal oil influenced the risk factors
of atherosclerosis in healthy volunteers.
Two intervention studies were carried
out as preliminary steps in a larger project
which aim at elucidating the disease preventive
potential of seal oil. In study I ten
healthy volunteers added 10 capsules of
seal oil to their normal Western diet
for six weeks. Blood tests were analysed
for total-, HDL-, and LDL-cholesterol
and plasma triglyceride, and the ratio
of n-6/n-3 fatty acid was determined in
plasma and erythrocyte membranes. In study
II we examined the effect in five healthy
volunteers who had only 5 capsules of
seal oil daily for six weeks. As an additional
test in study II, the effect on the proinflammatory
TNF-alpha cytokine in lymphocytes was
determined. A slightly decreased, however,
not significant effect was observed for
each of the cholesterol's after seal oil
supplementation. In both studies plasma
triglyceride, and the n-6/n-3 fatty acid
ratio of plasma and erythrocytes were
significantly reduced upon seal oil intake.
During the intervention period of study
II a distinct reduced level of TNF-alpha
was observed in isolated lymphocytes.
The examinations suggest that supplementation
of seal oil, 10 capsules or 5 capsules/day,
may have beneficial effects on factors
thought to be associated with cardiovascular
and thrombotic diseases. |
|
|
|
Long-chain
n-3 PUFA in fish oil have modulating effects
on inflammatory responses. The aim of
this open pilot study was to investigate
whether duodenal seal oil administration
would benefit patients with inflammatory
bowel disease (IBD). Seal oil (10 mL)
was administered three times a day directly
into the distal part of the duodenum via
a nasoduodenal feeding tube for 10 d in
10 patients, 5 of whom had Crohn's disease
and 5 ulcerative colitis. Nine of the
10 patients suffered from IBD-associated
joint pain. Various parameters of disease
activity and FA incorporation in tissues
were analyzed before and after treatment.
Following seal oil therapy, joint pain
index, disease activity, and serum cholesterol
level were significantly decreased, whereas
the n-3 to n-6 ratio both in intestinal
biopsies and blood was significantly increased.
Measures of calprotectin concentration
in gut lavage fluid, intestinal permeability,
and lipid peroxidation were not significantly
changed. The results suggest positive
effects of seal oil in patients with IBD,
especially on IBD-associated joint pain.
Further controlled studies are warranted. |
|
|
|
Results
from a research collaboration between
National Institute of Nutrition and Seafood
Research (NIFES) and Haukeland University
Hospital (HUH) indicate that seal oil
ameliorate musculoskeletal (joint) pain
in patients with chronic inflammatory
diseases like inflammatory bowel disease
(IBD). The results so far are promising,
but larger controlled studies are necessary
in order to confirm these results. |
|
|
The
research collaboration on seal oil between
NIFES and HUS started in 1998. Seal oil
is extracted from the seals' blubber and
contains a high proportion of the long
chained polyunsaturated omega-3 fatty
acids, similar to different kinds of fish
oil (approx. 20 %). Both refined and unrefined
oils from different seal species have
been used. All oils used complied with
legislation with respect to content of
undesirable substances. Patients at the
Institute of Gastroenterology, HUH, suffering
from gastrointestinal diseases were the
main target group in the research. |
|
|
A
pilot study, published in 2002(Arslan
et al. 2002), examined the effect of giving
seal oil to 10 patients suffering from
inflammatory diseases (IBD, chronic inflammatory
disease, ulcerative colitis, and Crohns
disease) and joint pain. When given seal
oil (10 ml, 3 times a day) for 10 days
via a (nasoduodenal) tube into the small
intestine, the patients reported an amelioration
of their joint pains. However, the intestinal
symptoms were only slightly improved.
The treatment was repeated for five of
the patients at a later stage, and they
were examined by a rheumatologist before
and after the treatment, confirming that
the joint pain was reduced.
The results
of Arslan's pilot study were confirmed
through a controlled study published in
2004 (Bjorkkjer et al. 2004). Here, 19
IBD patients with joint pain got the same
treatment with seal oil or soy oil for
10 days through a nasoduodenal tube, and
were followed up for 6 months after the
treatment by a rheumatologist. During
the study period the patients receiving
seal oil claimed improvement of their
joint pain compared to the patients given
soy oil. The effect of the seal oil lasted
up to several months after the treatment. |
|
|
|
A study
of nutrients in seal blubber and seal
meat was recently carried out and published
in Food Chemistry (Brunborg et al. 2005).
Seal blubber contains high proportions
of long chained unsaturated omega- 3 fatty
acids and mono unsaturated fatty acids.
Seal meat is lean (< 2 % fat) and is
protein rich with a well balanced amino
acid composition. In addition, it contains
a high concentration of minerals, especially
iron. Seal meat has high levels of vitamin
A, D3 and B12. More studies are at various
stages of publication (revised version,
submitted to be evaluated, or in progress)
and will be summarised here when they
are published.
More information: Arslan G., Brunborg
L.A., Froyland L., Brun J.G., Valen M.,
and Berstad A. (2002). Effects of duodenal
seal oil administration in patients with
inflammatory bowel disease. Lipids 37,
935-940. Bjorkkjer T., Brunborg L.A.,
Arslan G., Lind R.A., Brun J.G., Valen
M., Klemetsen B., Berstad A., and Froyland
L. (2004). Reduced joint pain after short-term
duodenal administration of seal oil in
patients with inflammatory bowel disease:
Comparison with soy oil. Scand. J. Gastroenterol.
11, 1088-1094. Brunborg L.A., Julshamn
K., Nordtvedt R., and Froyland L. (2005).
Nutritional composition of blubber and
meat of hooded seal (Cystophora cristata)
and harp seal (Phagophilus groenlandicus)
from Greenland. Food Chemistry (Article
in press).
|
|
|
|
|
Ikeda I
Yoshida H
Tomooka M
Yosef A
Imaizumi K
Tsuji H
Seto A
Laboratory of Nutrition Chemistry, Faculty of Agriculture, Kyushu University, Fukuoka, Japan.
Eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) were distributed mainly in the sn-1,3 positions of seal oil triglyceride and in the sn-2 position of squid oil triglyceride. Seal oil-rich or squid oil-rich fats having constant saturated/monounsaturated/polyunsaturated fatty acid (PUFA) and n-6/n-3 PUFA ratios were fed to exogenously hypercholesterolemic rats for 1 60 d. The control fat contained linoleic acid as the sole PUFA. Before starting the experimental diets, rats were orally treated with high doses of vitamin D for 4 d to accelerate atherogenesis.
The percentage of arachidonic acid in phosphatidylcholine and phosphatidylethanolamine of liver, platelets, and aorta was lower in the marine oil groups than in the control group, seal oil being more effective than squid oil. Maximal platelet aggregation induced by collagen was significantly lower in both marine oil groups. Platelet thromboxane (TX) A2 production induced by collagen or thrombin was markedly reduced by feeding seal or squid oils, the reduction being more pronounced in the seal oil than in the squid oil group.
Aortic prostacyclin (PGI2) production was the same among the three groups. The ratio of the productions of aortic PGI2 and platelet TXA2 was significantly higher in the seal oil than in the control group. Although there was no difference in intimal thickness among the three groups, the aortic cholesterol content was significantly lower in the marine oil groups than in the control group. These results showed that the main effects in rats of the different intramolecular distributions of EPA and DHA in dietary fats were on arachidonic acid content in tissue phospholipids and on platelet TXA2 production.
|
|
|
|
Osterud B
Elvevoll E
Barstaf H
Brox J
Halvorsen H
Lia K
Olsen JO
Olsen RL
Sissener C
Rekdal O, et al
Department of Biochemistry, University of Tromso, Norway
A study was performed to explore the effects of supplemental intake of various marine oils known to be part of the Eskimo diet. Healthy men and women (134) were randomly selected to consume 15 mL/d of oil from blubber of seal, cod liver, seal/cod liver, blubber of Minke whale, or no oil for ten weeks. Total cholesterol was unchanged in the oil groups, whereas high density lipoprotein cholesterol increased 7% in the seal/cod liver oil (CLO) group (P < 0.05) and 11% in the whale oil group (P < 0.005).
Triacylglycerol was significantly reduced in the CLO group only. The concentration of prothrombin fragment 1 + 2 was reduced 25% (P < 0.05) after whale oil supplementation. No change in fibrinogen or factor VIIc was detected. Tumor necrosis factor generation in lipopolysaccharide (LPS)-stimulated blood was 30% reduced after whale oil (P < 0.05), but was unaffected by intake of seal or CLO.
The LPS-induced tissue factor activity in monocytes was reduced to a significant degree only in the seal/CLO group (34%) and whale oil group (35%) (P < 0.05). The most dramatic change in thromboxane B2 in LPS-stimulated blood was seen after whale oil intake with 44% reduction (P < 0.01). Supplementation of a regular diet with a combination of seal oil and CLO and especially with whale oil seems to have beneficial effects on several products thought to be associated with cardiovascular and thrombotic diseases.
| |
|
|
|
Bente Deutch MPH, PhDCorresponding Author Contact Information, Eva Bonefeld Jorgensen Ph D and Jens C Hansen Dr Med
Department of Environmental and Occupational Medicine, Aarhus University, DK-8000, Arhus, Denmark
In a previous pilot study among healthy young Danes intake of 5 and 10 gram seal oil per day significantly reduced serum triglycerides but did not significantly influence total cholesterol, HDL-or LDL-cholesterol. The aim of the present study was to test and compare this effect of seal oil with intake of fish oil capsules in a controlled study.
The study was designed as a randomised, double blind, placebo controlled clinical trial, in which 78 young normolipidemic women were given 5 capsules a day of either fish oil, fish oil with B12, seal oil, or placebo consisting of ÒaverageÓ Danish fat, during a 3Ð4 months intervention period, followed by 8 weeks of washout period, no capsules.
The participants answered questionnaires about dietary habits, other lifestyle factors and anthropometric parameters. The compliance was followed by blood and gluteal fat lipid profiles. During the three months intervention there were gradual reductions in total serum cholesterol and triglycerides in all treatment groups.
In paired sample t-tests, the effects of fish oil with B12 were highly significant p<0.01 whereas fish oil alone, P=0.07, and seal oil, P=0.09, were borderline significant. Multiple regression analysis showed that the reductions in TG and atherogenic risk index were strongly correlated to concomitant increases of n-3/n-6 ratio in gluteal fat, an association which highly depended on the consumed n-3 dose and was independent of the type of marine oil used.
| |
| |
|
University of Bergen, Institute of Fisheries and Marine Biology Bergen Norway. 108 pp. Nov 2000.
The omega-3 polyunsaturated fatty acids (PUFA), eicosapentaenoic acid (20:5 omega -3, EPA) and docosahexaenoic acid (22:6 omega -3, DHA) have modulating effects on inflammatory mechanisms in the intestine and on the immune response in general.
EPA and DHA are incorporated into membrane phospholipids where they are replacing arachidonic acid (20:4 omega -6, AA). C20 fatty acids are the precursors of eicosanoids. When EPA is the precursor it inhibits competitively the formation of AA precursor eicosanoids, namely leukotrien (LT) B sub(4) and prostaglandin (PG) E sub(2), which are more potent in inflammation reactions than the products of EPA, namely LTB sub(5) and PGE sub(3). In the present study ten patients suffering from inflammatory bowel disease (IBD) were given 30 grams of seal oil (i.e. 4.4 grams of EPA + DHA) daily for a period of ten days. The oil was injected through a nasojejunal feeding tube directly to the jejunum to secure that a greater deal of omega -3 PUFA reached the inflamed area of the intestine.
The fatty acid composition of oils from marine mammals is somewhat different than oils from fish, regarding the positional distribution of the omega -3 PUFA (i.e, EPA and DHA). Analysis included fatty acid composition of serum, buffy coat, red blood cells and biopsies from rectal mucosa, gut lavage fluid calprotectin concentration, intestinal permeability, serum cholesterol (CH) and triacylglycerol (TAG) concentrations, and an indirect measurement of lipid peroxidation (TBARS concentration). In addition, scores of joint pain and disease activity were determined. The results showed that after seal oil supplementation, omega -3 fatty acids were incorporated at the expense of omega -6 fatty acids in all blood samples and rectal biopsies. Calprotectin concentration decreased slightly, whereas the intestinal permeability increased slightly. Serum CH and TAG concentrations were lowered. There was no sign of increased lipid peroxidation. Both joint pain index and disease activity were markedly lower after treatment with seal oil.
|
| |
|
Barbara Meyer 1, Amanda Lane 1, Neil mann 2
1 School of Health Sciences and Smart Foods Centre, University of Wollongong, NSW 2522
2 SCHOOL APPLIED SCEINCES (Food Science), RMIT University, Melbourne, 3000
Background - Numerous health benefits have been attributed to both eicosapentaenoic acid (EPA, 20:5n3) and docosahexaenoic acid (DHA, 22:6n3) found in fish oil. However, docosapentaenoic acid (DPA, 22:5n3) found particularly in red meat has been less well studied. Australians consume 6 times more meat than we do fish. The richest commercial capsule source of DPA available is seal oil. Objective - To compare the effects of DPA rich seal oil supplementation with DHA rich fish oil, on measures of plasma lipids in hypertriglyceridaemic subjects. Design - A randomised, parallel, placebo controlled, double blind study was conducted in 52 hypertriglyceridaemic subjects. They were randomly allocated to one of three groups receiving a total of 1g/d EPA, DPA & DHA but different relative amounts: seal oil capsules (360mg EPA, 250mg DPA, 450mg DHA), fish oil capsules (210mg EPA, 30mg DPA, 810mg DHA) or placebo capsules (containing a vegetable oil) for 6 weeks. Fasting blood samples were taken at baseline and at 6 week post intervention. Blood samples were tested for red blood cell (RBC) fatty acids and plasma lipids (triglycerides, total cholesterol, LDL-cholesterol and HDL-cholesterol). Results - The placebo group did not change at all in any of the parameters measured. Seal oil supplementation significantly increased incorporation of DPA (from 2.5-2.7%), DHA (from 4.9-5.8%) and EPA (from 1-1.8%), p<0.0005), whereas fish oil increased incorporation of DHA only (from 5.2-6.2%), p<0.01 into RBC. Baseline plasma triglyceride levels were not significantly different between the 3 groups. Plasma triglycerides remained unchanged in the placebo group (2.30-2.36mmol/l), whilst reductions of 7% (2.24-2.09mmol/l) and 14% (2.54-2.19mmol/l) were seen in the fish oil and seal oil groups respectively, but only the seal oil group reached significance (p<0.05). No differences were seen in any groups in HDL-cholesterol levels. Conclusion Ð Seal oil supplementation increased RBC levels of DPA, EPA and DHA whilst DHA rich fish oil supplementation increased RBC levels of DHA only. It appears that seal oil is more effective than fish oil at lowering plasma triglyceride levels in hypertriglyceridaemic subjects.
Acknowledgement - Supported by funding from Meat and Livestock Australia
|
|
| |
|
|
