The Cardiovascular Benefits of Omega-3 Fatty Acids

1. NMR News: Volume 3, Issue 2, February 2010
The Cardiovascular Benefits of Omega-
3 Fatty Acids
By: Charles Spielholz, Ph.D.
Abstract: Evidence in the biomedical literature supports a role for omega-3 fatty acids in
cardiovascular health. Based on the strength of this evidence, the American Heart Association
recommends that healthy people eat two servings of fatty fish per week in order to help maintain a
healthy cardiovascular system.
T
he omega-3 fatty acids appear to have docosahexaenoic acid. In this mini-review, the
positive effects on human health. Evidence role played by omega-3 fatty acids in
in the primary literature suggests roles for cardiovascular health will be examined.
these fatty acids in heart health, inflammation,
the central nervous system, and in mental health. There is much evidence in the biomedical
It is clearly known that omega-3 fatty acids are literature to show that the omega-3 fatty acids
components of cell membranes and are also play a role in cardiovascular health (1), and that
involved in some cellular signal transduction supplements containing omega-3 fatty acids have
processes. Some of the omega-3 fatty acids can beneficial effects on cardiovascular health. These
be synthesized by humans from other molecules. include lowering triglyceride levels (2,3),
Those omega-3 fatty acids that cannot be preventing arrhythmias (4,5) decreasing
synthesized but are required by humans for inflammation (4), decreasing platelet
normal physiological and biochemical function aggregation (clotting) (6), and stabilizing plaques
are termed essential and must be obtained in the (7). There is also a report that omega-3 fatty acids
diet. Essential omega-3 fatty acids include alpha- may lower blood pressure (8), although that
linolenic acid, eicosapentaenoic acid, and observation has not been clearly replicated. The
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2. NMR News: Volume 3, Issue 2, February 2010
effect of omega-3 fatty acids on lowering indicated that alpha-linolenic acid decreases level
triglyceride levels appears to be most of C-reactive protein, but not total cholesterol,
pronounced in people with the highest levels of LDL cholesterol or triglycerol levels (21,22).
triglycerides, that is those people with the
greatest risk (2). Eicosapentaenoic acid and docosahexaenoic acid
are long chain omega-3 fatty acids. Although not
Omega-3 fatty acids supplements also appear to quite as well studied as alpha-linolenic acid,
be helpful in people undergoing treatment for eicosapentaenoic acid and docosahexaenoic acid
cardiovascular disorders. Omega-3 fatty acids have been shown to decrease the risk of
appear to enhance the effect of statin drugs, arrhythmia and thrombosis, decrease the
which are used to lower cholesterol (2,9,10). development of plaque along blood vessel walls,
Published evidence also indicates that omega-3s decrease serum triglycerides, decrease
may be helpful in people with implanted inflammation, and to cause a small decrease in
defibrillators, although the results of this work blood pressure (23,24).
are not yet definitive (11,12,13). At least one study
indicated that omega-3s improve results for The observations and studies listed above all
patients who have undergone bypass surgery require further investigation in order to
(14). understand the exact mechanism by which these
omega-3 fatty acids function. However, it is clear
Several studies assessing the effect of specific that omega-3 fatty acids promote heart health
omega-3 fatty acids on cardiovascular health and do not appear to have any serious side
have been performed. The fatty acids studied effects. In fact the benefits of omega-3 fatty
were alpha-linolenic acid, eicosapentaenoic acid, acids for cardiovascular health are so convincing
and docosahexaenoic acid. Alpha-linolenic acid that the American Heart Association
cannot be synthesized by humans and is required recommends that healthy people obtain omega-3
in the diet. In two large studies, one with 45,000 fatty acids in their diets by eating fatty fish, such
men over a 14 year period and one with 76,000 as salmon, twice a week (25). It has been shown
women over a 10 year period, increases in alpha- that the cardiovascular benefit of eating fatty fish
linolenic acid intake were associated with outweighs any risks that may arise from eating
significant decreases in cardiovascular disease fish that may be contaminated with pollutants,
and fatal cardiovascular disease, respectively such as mercury (26).
(15,16). Two additional large scale studies
confirmed these results (17,18) although two
studies did not (19,20). Additional research has
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3. NMR News: Volume 3, Issue 2, February 2010
Figure Legend: Structures of omega-3 fatty acids that are considered to be heart healthy.
(1) Eicosapentaenoic acid
(2) Docosahexaenoic acid
(3) Alpha-linolenic acid
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4. NMR News: Volume 3, Issue 2, February 2010
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5. NMR News: Volume 3, Issue 2, February 2010
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