Omega-3
EPA是抑鬱症有效的百憂解 Omega-3 EPA ‘is as effective as Prozac’ for depression
A
growing number of observational and epidemiological studies
have suggested that major depression is associated with reduced
dietary intake and/or cellular levels of omega-3 polyunsaturated
fatty acids. Indeed, it has been previously shown that individuals
suffering from major depression are more likely to have low
levels of EPA in both plasma and red blood cell phospholipids
but it has not been clear if these are the result of depression
or whether these deficiencies give rise to depressive symptoms.
Whilst the use of omega-3 fatty acids in the treatment of
depression is not new, a recent double blind, randomised trial
published in March 2008 in the New Zealand Journal of Psychiatry
[1] has shown that EPA taken alongside Prozac is therapeutically
more effective in treating the symptoms of depression than
taking Prozac alone. The study recruited a total of 60 outpatients
diagnosed with major depressive disorder who were randomly
allocated to receive daily doses of either 1000mg EPA or 20mg
Prozac, or a combination of the two. Severity of depression
was assessed using the Hamilton Depression Rating Scale (HDRS)
as the primary outcome measure and individuals were assessed
every two weeks over an eight-week period.
Using the Hamilton Depression Rating Scale (HDRS), these
patients originally showed an average score of 15 out of the
17-item HDRS. The study showed that Prozac and EPA appeared
to be equally effective in controlling depressive symptoms,
based on a decrease in HDRS scores, while the two combined
showed significantly better results. This study further supports
that fact that simply by supplementing with a highly purified
product containing EPA we can directly influence our health
and our overall feeling of well-being.
Whilst the exact mechanism of the role of EPA in the treatment
of depression is still unclear, there are certain hypotheses
that are beginning to unfold. Prozac is an antidepressant
that falls under the category of a selective serotonin reuptake
inhibitor or SSRI. Low serotonin levels are a symptom, rather
than a cause, of depression and SSRIs work by increase the
levels of serotonin by inhibiting its reuptake and therefore
increasing the level of serotonin in the blood. EPA has also
been shown to block the uptake of serotonin by cells and therefore
may work in a similar fashion to that of Prozac. In addition,
individuals with depression have been shown to have increased
levels of substances called inflammatory cytokines resulting
in an increased state of inflammation that may be associated
with symptoms such as fatigue, fever, lack of sleep, pain,
and aching. EPA is converted within the body to anti-inflammatory
eicosanoids and so by increasing EPA levels the body can help
buffer these inflammatory agents, and help to alleviate symptoms.
Interestingly, DHA - another long chain fatty acid found in
the majority of fish oil supplements - has been found to increase
the levels of these inflammatory cytokines which may explain
why combinations of EPA and DHA are not as efficient in the
treatment of depression as that of EPA alone.
Dr Alex Richardson, neurophysiologist at the University of
Oxford who runs the food and behaviour research charity FAB
Research (www.fabresearch.org.uk), welcomed the study’s findings:
“According to WHO, depression now makes the single biggest
contribution to the overall burden of ill-health in developed
countries like the UK,” she said.
“A number of trials have already shown that omega-3 from
fish oils (and particularly EPA) can benefit patients with
depression or bipolar disorder. This is why the American Psychiatric
Association has already recommended treatment with at least
1g/day of EPA and DHA for these conditions - but as an addition
to standard treatment, not as an alternative.”
Omega product is a patented formulation of completely natural long-chain
omega fatty acids. It contains a unique ratio of ultra-pure
EPA (the omega-3 eicosapentaenoic acid) and cold-pressed,
non-raffinated, virgin evening primrose oil (containing the
omega-6 gamma-linolenic acid). As such, omega product combines the
benefits that both these natural substances bring to the body.
Fatty acids play an important part in the functioning of
every living cell in the body. Specifically they may help
the body in several ways including: improving the circulatory
system, aiding concentration, maintaining a well-balanced
state of mind and keeping joints in good condition.
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