Two studies I have looked suggest that it's not too much Omega 3s that
are the culprit behind greater hemmorrhagic stroke in Eskimos, but the
relative lack of linoleic acid. Thsu the plot thickens, if not the blood.
http://www.ajcn.org/cgi/content/abstract/28/9/958:

Fatty acid composition of the plasma lipids in Greenland Eskimos

J Dyerberg, HO Bang and N Hjorne

Gas-liquid chromatography analyses have been carried out to investigate
the composition of esterified fatty acids in the plasma lipids in 130
Greenland Eskimos, compared with those of 32 Greenland Eskimos living in
Denmark and of 31 Caucasian Danes in Denmark. While the Eskimos living
in Denmark did not differ substantially from other persons living in
Denmark and, from what is found in other studies in Western communities,
the Greenland Eskimos showed a completely different pattern. They
demonstrated a much higher proportion of palmitic, palmitoleic, and
timnodonic acids, while they had a markedly lower concentration of
linoleic acid. The total concentration of polyunsaturated fatty acids
was lower in Greenland Eskimos than in the other groups. These findings
are discussed in the light of the generally accepted opinion of the
beneficial effect on plasma lipid levels and on the morbidity of
coronary atherosclerosis of a high dietary intake of polyunsaturated
fatty acids. As plasma lipid and lipoprotein levels in Greenland Eskimos
in a previous study were found markedly lower than those found in
Western populations, and as coronary atherosclerosis seems to occur far
less commonly among Eskimos in Greenland than among peoples in
industrialized countries, it was found difficult to combine these
observations with the results from the present study. If dietary
differences are the main reason for the differences in plasma lipid
concentrations, the results from the present study point more toward
qualitative than toward quantitative differences in respect of fatty
acid composition of the food.


Another study I found that suggests that linoleic acid may be protective

Stroke. 2002;33:2086.)
© 2002 American Heart Association, Inc.

Original Contributions

Linoleic Acid, Other Fatty Acids, and the Risk of Stroke
Hiroyasu Iso, MD ;Shinichi Sato, MD ;Utako Umemura, PhD ;Minako Kudo
;Kazuko Koike, PhD ;Akihiko Kitamura, MD ;Hironori Imano, MD ;Tomonori
Okamura, MD ;Yoshihiko Naito, MD ;Takashi Shimamoto, MD

  From the Department of Public Health Medicine, Institute of Community
Medicine, University of Tsukuba, Ibaraki-ken (H.I., M.K.); Osaka Medical
Center for Health Science and Promotion, Osaka (S.S., A.K., H.I., Y.N.,
T.O., T.S.); Tokyo Bunka Junior College, Tokyo (U.U.); and Center for
Medical Science, Ibaraki Prefectural University of Health Science,
Ibaraki-ken (K.K.), Japan.

Correspondence to Dr Hiroyasu Iso, Department of Public Health Medicine,
Institute of Community Medicine, University of Tsukuba, 1-1-1 Tennodai,
Tsukuba-shi, Ibaraki-ken 305-8575, Japan. E-mail [log in to unmask]

Background and Purpose —The role of serum fatty acids as a risk factor
for stroke and stroke subtypes is largely unknown.

Methods —A prospective nested case-control study of Japanese 40 to 85
years of age was conducted through the use of frozen serum samples from
7450 participants in cardiovascular risk surveys collected from 1984 to
1989 for 1 community and 1989 to 1992 for the other 2 communities. By
the end of 1998, we identified 197 incident strokes whose subtypes were
confirmed by imaging studies. Three controls per case were selected by
matching for sex, age, community, year of serum storage, and fasting
status.

Results —Compared with controls, total (n=197), hemorrhagic (n=75), and
ischemic (n=122) strokes had similar proportions of n3 polyunsaturated
fatty acids, lower proportions of linoleic and arachidonic acids, and
higher proportions of saturated and monosaturated acids, determined by
gas chromatography. The multivariate odds ratios associated with a 1-SD
increase in linoleic acid (5%) after adjustment for hypertension,
diabetes, serum total cholesterol, and other cardiovascular risk factors
were 0.72 [95% confidence interval (CI), 0.59 to 0.89] for total stroke,
0.66 (95% CI, 0.49 to 0.88) for ischemic stroke, 0.63 (95% CI, 0.46 to
0.88) for lacunar infarction, and 0.81 (95% CI, 0.59 to 1.12) for
hemorrhagic stroke. The respective odds ratios for saturated fatty acids
(4%) were 1.13 (95% CI, 1.05 to 1.65), 1.35 (95% CI, 1.01 to 1.79), 1.44
(95% CI, 1.03 to 2.01), and 1.21 (95% CI, 0.82 to 1.80). Further
adjustment for other fatty acids attenuated these relations, but the
relation between linoleic acid and risk of ischemic stroke remained
statistically significant.

Conclusions —A higher intake of linoleic acid may protect against
ischemic stroke, possibly through potential mechanisms of decreased
blood pressure, reduced platelet aggregation, and enhanced deformability
of erythrocyte cells.

This quote is from the text of the whole article: "The n3
polyunsaturated fatty acids were not associated with the risk of total
stroke or any stroke subtypes" and this in the conclusion: "There was no
association of n3 polyunsaturated fatty acids with the risk of
hemorrhagic or ischemic strokes. This finding is not surprising because
serum n3 polyunsaturated fatty acid levels (range, 2.7% to 22.0%) were
still lower than that of Greenland Eskimos 26 in whom an excess
mortality from hemorrhagic stroke was reported. 27 Elongation of
bleeding time appears only when the proportion of serum n3 fatty acids
exceeds 20%, 28 corresponding to only 2% of the subjects in the present
study. One possible reason for the lack of association between n3
polyunsaturated fatty acids and ischemic stroke was that most of the
subjects in the present study had quite high levels of n3
polyunsaturated fatty acids, which are likely to protect against
ischemic stroke. Previous prospective studies have demonstrated that a
small amount of fish and n3 polyunsaturated fatty acid intake or several
weekly servings of fish were associated with a significant risk
reduction for ischemic stroke. 29 ,30" .......


http://stroke.ahajournals.org/cgi/content/full/33/8/2086#TBL4

The Greenland eskimos sound like an anomaly -- Americans get so much
more of a mixture of fats, especially the omega 6 type.


Oddly enough it seems that eskimos have lower rates of other kinds of
stroke (eg. Thrombotic and CVD). Yes I do think molecularly distilled
fish oil can have a beneficial effect -- if only to balance all the
omega 6 fats that dominate the American diet as well as a supplement to
target specific health conditions such as arthritis, ADD, bipolar and
depression, CVD, etc. Obviously one can get too much of a good thing --
if one gets plenty of omega 3s in your diet and have no particular
health condition that could benefit from supplementation I agree it
would be counter-productive to use fish oil.

Namaste, Liz

[log in to unmask] wrote:

   Anyway, there are

>> different kinds of strokes.  Thrombotic strokes for instance involve
cerelbral
>> clots.  Hemorrhagic strokes involve bleeding in the brain.  There
are studies
>> showing Eskimos have higher rates of hemorrhagic strokes which are
much less
>> common than the other kind.  This makes sense because fish oil is a
blood
>> thinner.  If you overdo a blood thinner -- you could get unwanted
bleeding.  It's why
>> before surgery the doctor will ask you to stop vitamin E, fish oil
and other
>> blood thinners for a period of time before the operation.
>>
>> I believe that Omega-3s are useful to some extent or I wouldn't eat
sardines
>> every day.  However, I still remain convinced that massive doses of
fish oil
>> supplements ultimately create more harm than good. Gobbling capsules
is always
>> a far cry from eating real food.  You obviously feel that fish oil
is useful
>> and that's your perogative.  In any event, I really don't see the
point in
>> harping on this topic any further.  Let's just agree to disagree.



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