Omega 3 fatty acids and cardiovascular disease—fishing for a natural treatment
BMJ 2004; 328 doi: https://doi.org/10.1136/bmj.328.7430.30 (Published 01 January 2004) Cite this as: BMJ 2004;328:30
All rapid responses
Omega 3 fatty acids and cardiovascular disease—fishing
for a natural treatment by Jehangir N Din, David E
Newby and Andrew D Flapan.
http://www.bmj.com/cgi/content/full/328/7430/30?
ijkey=66b98811d643dc0623e73f95dbc45848d784dca0&keytype2
=tf_ipsecsha
Dear Sir,
This article states that omega - 3 fatty acids
(provided as capsules) reduce triglyceride
concentrations in a dose dependent manner, with
intakes of about 4 g per day.
Do you mean by this the "fill weight" of the capsules or
only the weight of the omega - 3 fatty acids?
And what about the ratio between eicosapentanoic acid
and docosahexanoic acid within the omega 3 itself?
For a Mor EPA capsule for example, the ratio between
EPA an DHA is 7 to 1, but for other products the ratio
is 1,5 to 1.
One softgel "Mor EPA" of 1000 mg contains 75% Omega-3,
of which 580 mg EPA and 83 DHA 83 mg.
But in case of BIOLEINE, 1000 mg contains 54% Omega-3,
of which 270 mg EPA and 170 mg DHA.
Which product would you suggest? And how many capsules
a day?!
Sincerely,
Gilbert De Bruycker
Competing interests:
None declared
Competing interests: No competing interests
i found the article by Din et al very informative, but am unclear why
they chose to ignore the plant derived omega 3 fatty acids beyond the
initial difinitions.
In figure 3, they suggest that the omega 3 fatty acids from fish oils
are metabolites of alpha linolenic acid (the plant derived source of omega
3 fatty acids). However, no comment was made on whether alpha linolenic
acid is as effective as oily fish in the beneficial effects described. Is
this because no tials exist or trials show less effect?
Din et al comment on concerns about depleting fish stocks and
environmental contamination of certain fish.
Would suggesting a trial of alpha linolenic acid supplements or a
diet rich in the plant sources of this oil as well as their proposed trial
of fish oil supplements be an option for future research?
Competing interests:
None declared
Competing interests: No competing interests
The clinical review on the possible protective effect of omega 3
fatty acids against cardiovascular disease refers to the originating work
on this topic of Dyerberg et al[1] but does not mention that these
investigators also reported that “dairy foods are very scarce in the
Eskimo diet”.[2] Related to this restriction is a high prevalence of low
lactase activity in adulthood (an inherited characteristic), estimated as
87%.[3]
Similarly, of the countries of the Organisation for Economic
Cooperation and Development, Japan has the lowest mortality from ischaemic
heart disease (IHD), the highest per capita supply of fat from fish, the
lowest per capita supply of milk, and the highest prevalence of low
lactase activity in adults, estimated as 78%.[3]
IHD prevalence and mortality are also relatively low in China, where
milk provides only 8 calories per capita daily, and the estimated
prevalence of low lactase activity in adults is 94%,[3] but the per capita
supply of fat from fish is low - less than half that in the UK.[4]
During the Second World War, Norway experienced a decline in
mortality from ‘arteriosclerosis’, a term which included IHD. A study in
Oslo showed that the consumption of “milk of all sorts” was the lowest and
that of fish was the highest ever found in Norway.[5]
The MRC seeks more non-pharmaceutical clinical trials. It should
compare a high intake of omega 3 fatty acids with a milk-free diet in
secondary prevention following myocardial infarction.
References
1. Dyerberg J, Bang HO, Hjorne N. Fatty acid composition of the
plasma lipids in Greenland Eskimos. Am J Clin Nutr 1975; 28:958-66.
2. Bang HO, Dyerberg J, Hjorne N. The composition of food consumed
by Greenland Eskimos. Acta Med Scand 1976;200:69-73.
3. Segall JJ. Dietary lactose as a possible risk factor for
ischaemic heart disease: review of epidemiology. Int J Cardiol 1994;46:197
-207.
4. Food and Agriculture Organization of the United Nations. Food
Balance Sheets, 1984-86 Average. Rome: FAO,1991.
5. Strom A. Examination into the diet of Norwegian families during
the war-years, 1942-45. Acta Med Scand 1948;138(suppl 214):1-47.
Competing interests:
None declared
Competing interests: No competing interests
Editor- Concern about depletion of fish stocks will not be addressed
by supplementing animal feed with fish oil as suggested by Din et al (1),
as this requires the harvesting of wild fish to provide the fish oil.
Fish farming does not provide a solution as farmed fish contains less
omega 3 fatty acids, this being dependent on what they are fed – usually
wild caught fish products (2).
However, the original source of the long chain omega 3 fatty acids
found in fish are the chloroplasts of marine algae and phytoplankton at
the bottom of the food chain (3). In the marine environment the
polyunsaturated fatty acids may provide the degree of desaturation needed
to keep cell membranes fluid in cold water. Rather than genetically
modifying terrestrial plants to produce eicosapentaenoic and
docosahexanoic acid, it is possible to culture marine algae industrially
to provide the “fish” oil while leaving the fish alone (4).
If using cod liver oil as a source of fish oil it is important to
remember that this contains a relatively high concentration of vitamin A
producing a risk of toxicity (5).
1. Din JN, Newby DE, Flapan AD. Omega 3 fatty acids and
cardiovascular disease-fishing for a natural treatment. Br Med J
2003;328:30-35.
2. van Vliet T, Katan MB. Lower ratio of n-3 to n-6 fatty acids in
cultured than in wild fish. Am J Clin Nutr 1990;51:1-2.
3. Nordoy A, Dyerberg J. n-3 fatty acids in health and disease. J
Intern Med 1989;225 Suppl 1:1-3.
4. Wen ZY, Chen F. Heterotrophic production of eicosapentaenoic
acid by microalgae. Biotechnol Adv 2003:21:273-294.
5. Grubb BP. Hypervitaminosis A following long-term use of high-
dose fish oil supplements. Chest 1990;97:1260.
Competing interests:
MDB has received research funding from Scotia Pharmaceuticals and Ross Products Division for work involving fish oil-based preparations
Competing interests: No competing interests
Sir,
This is another timely review that again stresses the availability of
powerful prevention means very much cheaper than more widely marketed
drugs (statins, powerful antiaggregant drugs...). In addiction, it seems
likely that the side effects should be markedly less severe and prevalent
with omega-3 fatty acids than with those drugs! Physicians should be more
aware and it is a nice choice of the BMJ to publish this review.
The authors restricted their review to the marine source elongated
omega-3 fatty acids. But alpha-linolenic acid (ALA) is easily available,
and specifically as they wrote, in canola (rapeseed) oil, soybean oil, in
some vegetable, and even in Alpine Swiss cheese (1) (as Pr Kayser modestly
did not mention in his e-letter). Moreover, ALA sources are less likely to
be contaminated with mercury. The question of the possibility of
hypervitaminosis D with a diet too rich in fish oil was not addressed by
the authors: is there a risk or not, and what would be the threshold ?
I'd also like to ask the authors about the omega- 3 contents of fish
obtained from aquaculture rather than wild.
Whereas the Lyon study's impressive results have never been
reproduced (nor proved erroneous) (2-4) we should remember that the
"Cretan diet" prescribed in that study is not too uneasy to achieve in a
western country, is palatable, is easy to adhere to, and that all pieces
of evidence (experimental, epidemiologic, therapeutic) (2-6) point to the
high likeliness that this is a very protective diet against coronary
disease and probably cancer or more (7). The "Cretan diet" of that study
is easy to reproduce and includes frequent fish meals.
It seems highly unlikely that the Lyon-study-like Cretan-
Mediterranean diet (published 1994) bears any risk except for the
pharmaceutical , meat, sunflower and milk industries, therefore …
1- Hauswirth CB, Scheeder MR, Beer JH. High {omega}-3 Fatty Acid
Content in Alpine Cheese. The Basis for an Alpine Paradox. Circulation.
2003 Dec 15
2-de Lorgeril M, Renaud S, Mamelle N, Salen P, Martin JL, Monjaud I,
Guidollet J, Touboul P, Delaye J. Mediterranean alpha-linolenic acid-rich
diet in secondary prevention of coronary heart disease. Lancet. 1994 Jun
11;343(8911):1454-9.
3-Leaf A. Dietary prevention of coronary heart disease: the Lyon Diet
Heart Study. Circulation. 1999 Feb 16;99(6):733-5.
http://circ.ahajournals.org/cgi/content/full/99/6/733
4- Leaf A, Kang JX, Xiao YF, Billman GE. Clinical prevention of sudden
cardiac death by n-3 polyunsaturated fatty acids and mechanism of
prevention of arrhythmias by n-3 fish oils. Circulation. 2003 Jun
3;107(21):2646-52
5-Singh RB, Dubnov G, Niaz MA, Ghosh S, Singh R, Rastogi SS, Manor O,
Pella D,Berry EM. Effect of an Indo-Mediterranean diet on progression of
coronary artery disease in high risk patients (Indo-Mediterranean Diet
Heart Study): a randomised single-blind trial. Lancet. 2002 Nov
9;360(9344):1455-61.
6-Sandker GN, Kromhout D, Aravanis C, et al. Serum cholesteryl ester fatty
acids and their relation with serum lipids in elderly men in Crete and The
Netherlands. Eur J Clin Nutr 1993; 47: 201-08.
7-de Lorgeril M, Salen P, Martin JL, Monjaud I, Delaye J, Mamelle N.
Mediterranean diet, traditional risk factors, and the rate of
cardiovascular complications after myocardial infarction: final report of
the Lyon Diet Heart Study.Circulation. 1999 Feb 16;99(6):779-85.
http://circ.ahajournals.org/cgi/content/full/99/6/779
Competing interests:
None declared
Competing interests: No competing interests
Sir,
I read with interest your review on omega 3 fatty acids and
cardiovascular disease. It is clear that there is a role for these fatty
acids in the prevention and treatment of cardiovascular disease. I was,
however, astonished that you did not even once mentioned the tantamount
importance of regular physical activity for the prevention and treatment
of cardio-vascular disease. But the evidence is there, a sedentary life
style is a major risk factor for the development of cardiovascular and
other disease. It is a combination of regular physical activity and
adequate nutrition that is needed. In order to give the reader an
integrated view of the topic, in a review on one particular aspect of
nutrition one should at least once mention the great importance of the
other determinant, regular physical activity, which on the basis of our
evolutional history is perhaps even more 'natural' as eating a diet rich
in oily fish.
Sincerely,
Bengt Kayser
Competing interests:
None declared
Competing interests: No competing interests
Sirs,
notoriously, all authors agree with the use of fish or fish oil
supplements after myocardial infarction (1), as well as in people at
“real” risk of coronary heart disease, recognized now-a-days rapidly and
easily at the bed-side with the aid of Biophysical Semeiotics (2, 3) (See
webb site HONCode 233736, www.semeioticabiofisica.it, Practical
Application). Although the mechanisms by which fish oils confer their
benefits are not fully understood, a more accurate research in the large
letterature on omega 3 fatty acids action mechanisms could certainly help
excellent authors, like Din JN. Et al (1), to enlighten this particular
aspect of treatment with fish or fish oil, as I described previously,
already 11 years ago (4, 5). As a matter of fact, among the well-known
effects of omega-3 (antiarrhythmic, antithrombotic, antiatherosclerotic,
anti-inflammatory, improves endothelial function, lowering blood pressure
lowering triglyceride concentrations) there are other essential,
underlying actions mechanisms, unfortunately “overlooked also by the above
-mentioned colleagues: free radical scavenger action and potent
stimulation of both mitochondrial Q10 Circle and Co Q10 synthesis (4, 5).
These effects, in my opinion, play a primary role in action mechanisms of
omega-3, and account for the reason they are useful in a lot of diseases,
including also IMA, CAD, and CAD prevention, obviously necessarily
associated with other therapeutic measures, first of all, diet,
etimologically speaking, i.e., proper food, physical exercise, a.s.o.
1) Din J.N., Newby D.E., Flapan A:D. Omega 3 fatty acids and
cardiovascular disease—fishing for a natural treatment
BMJ 2004;328:30-35 (3 January), doi:10.1136/bmj.328.7430.30
2) Stagnaro-Neri M., Stagnaro S., Deterministic Chaos, Preconditioning and
Myocardial Oxygenation evaluated clinically with the aid of Biophysical
Semeiotics in the Diagnosis of ischaemic Heart Disease even silent. Acta
Med. Medit. 13, 109, 1997
3) Stagnaro Sergio. A clinical efficacious maneouvre, reliable in bed-side
diagnosing coronary artery disease, even initial or silent, as well as
"heart coronary risk". 3rd Virtual International Congress of Cardiology,
FAC, http://www.fac.org.ar/tcvc/marcoesp/marcos.htm
4) Stagnaro-Neri M., Stagnaro S., Acidi grassi W-3, scavengers dei
radicali liberi e attivatori del ciclo Q e della sintesi del Co Q10. Gazz.
Med. It. – Arch. Sc. Med. 151, 341 (Infotrieve)1992
5) Stagnaro-Neri M., Stagnaro S., Proprietà antiossidante degli acidi
grassi W-3. Gazz. Med. It. – Arch. Sc. Med. 151, 27, 1992.
Competing interests:
None declared
Competing interests: No competing interests
Re: Omega 3 fatty acids and cardiovascular disease
Dear Gilbert:
I would like to make some suggestions for you so you can better understand
Omega 3 supplements. I work for a nutrional co. and have read 3 books on
Omega 3 fatty acids, not to mention have taken them personally for the
past 5 years. When it is mentioned that you should consume an intake of 4
grams per day, that refers to the amount of Omega 3 only. It does not mean
the total fill amount as you questioned. It is not the total amount of fat
in grams that is significant but the amount of Omega 3's. The higher
percentage of Omega 3's the better. All you have to do is add the total
amt. of EPA and DHA and take that total amt. and divide it into the total
amt of fat grams. So if you have 450mg of EPA and 250mg of DHA and a total
of 1.5 mg of fat, you would come up with the following formula (just an
example). 450+250=700mg of total Omega 3's
1.5grams=1500mg 700/1500=46.6% concentration. As far as ratio's go, the
standard amount is 2:1 EPA/DHA but some people, like myself do better with
a ratio as high as 6:1 EPA/DHA. Some people receive a side effect of
decreased mood with too much DHA. I believe that EPA is more beneficial to
mood and Cardiovascular disease prevention among the many other benefits.
I think you should try to find a product with at least 70% potency and
with the highest ratio of EPA to DHA ratio. Your body hangs on to DHA much
more then EPA. EPA is much more rapidly turned over and needed to be
replaced in the diet or through supplementation daily. The only
differences would be pregnant women, nursing Mothers and babies who need
more DHA. One product I can suggest is called OmegaBrite and you can
receive all the info at www.OmegaBrite.com and it is a pharmaceutical
grade product, however if that is too pricey, there is an excellent
product that most Wal-Marts carry called Omega HMJ (Heart, Mind, Joints).
It comes in a blueish silver box with 45 caps. for $5.94 which should
cover a month's worth if you consume 1000mg a day or 1 gram a day of omega
3's. I hope this helps.
Competing interests:
None declared
Competing interests: No competing interests