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| Omega-3 Fatty Acids |  |
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| Before You Begin Information presented here is for general educational purposes only. Each one of us is biochemically and metabolically different. If you have a specific health concern and wish my personalized nutritional recommendation, write to me by clicking here. |
Contents
Introduction
Definition Of Omega 3 Fatty Acids
Fish oil - As good as it sounds
How does Omega-3 Work
Statin Drugs
Lower Triglycerides
Anti-arrhythmic
Depression
What About ALA
How Much omega-3 In The Diet
Sources Of Omega-3
Optimum Dosage
Side Effects
Contamination Issues
Balance of Omega-3 to Omega-6 Fatty Aicds
There is an increase
of awareness in the role of omega-3 fatty acids. Omega-3 fatty acids
are found in fish and fish oils and aid in the prevention and management
of heart diseases. This can help reduce your risk of developing
an abnormal heartbeat; which can lead to heart problems and even sudden
death.
Greater
than half of all sudden death from cardiac causes have no history of cardiovascular
disease. In
fact, over 40% of all heart attack victim autopsies show clear coronary
vessels. Clearly, there is much more going on than the simple "cholesterol
kills" hypothesis. It is interesting to note that the
first
and most common sign of cardiovascular disease in post-menopausal women
is
death.
Yes, death.
In other words, there are no signs or symptoms.
Omega-3
fatty acids provide a range of benefits and protection for the heart and
our body.
In addition
to reducing the risk of heart disease, they also help prevent blood clotting,
heart attacks and irregular heartbeats that could lead to sudden cardiac
death. They are anti-inflammatory, and inflammation is a key initiator of
the atherosclerotic cascade leading to plaque formation and sudden death.
Omega-3 also have anti-cancer functions as we shall see.
Omega-3
fatty acids can be divided into 3 main categories -- Eicosapentaenoic Acids
(EPA), Docosahexaenoic Acids (DHA) and Alpha-Linolenic Acids;
out
of which EPA and DHA have the most beneficial effects.
EPA and DHA
are found mainly in fish oils while Alpha-Linolenic Acids are usually derived
from plant sources such as soybeans, canola, walnut and flaxseed.
DEFINITION OF OMEGA
3 FATTY ACIDS
Omega-3 fatty
acids are long-chain
polyunsaturated fatty acids
(18-22 carbon atoms in chain length) with the first of many double bonds
beginning with the third carbon atom (when counting from the methyl end
of the fatty acid molecule).
The fish-based and
fish-oil-based omega-3 polyunsaturated fatty acids (also referred to as
n-3 PUFA) consist of EPA (20 carbon atoms, 5 double bonds) and DHA (22 carbon
atoms, 6 double bonds).
Some plant foods and vegetable oils do contain varying amounts of the n-3
PUFA Alpha-Linolenic Acid (ALA), which has 18 carbon atoms and 3 double
bonds. Many vegetable oils are also rich in omega-6 fatty acids. Some examples
are Linolenic acid in corn, safflower, sunflower and soybean oils.
Non-hydrogenated Canola oil, ground flaxseed and walnuts are rich sources
of ALA.
Fish oil -
As good as it sounds?
Of
all the fatty acids in the blood including saturated, monounsaturated, and
polyunsaturated, only
the percentage of long chain omega-3 predicted fewer sudden death.
In a study of 11,323 recent survivors of heart attack, either 1 gram of
omega-3 or 300 mg of Vitamin E or both was given. The usual pharmacological
regiment and lifestyle recommendations were made. It was shown that omega-3
and not Vitamin E improved survival. After 3 months of remaining on regiment
of omega-3, patterns showed a 41% decrease in mortality, a 53% reduction
in sudden death after 4 months, and after 12 months, a 30% decrease in cardiovascular
mortality. There was also a 5% decrease in triglyceride but not total cholesterol,
HDL, or LDL cholesterol.
Other studies have shown that:
1. When comparing the Greenland Inuit
and the Dutch, the former exhibit a significantly lower death rate from
acute myocardial infarction despite only moderate differences in their blood
cholesterol levels. This is because the Inuit's diet is high in fat and
provides up to several grams of omega-3 fatty acid daily, primarily in the
form of marine mammals, wildfowl and various fish.
2. In Japan, where fish intake forms a large proportion in their diet, the
mortality rates arising from various types of heart disease is significantly
lower than other countries like North America.
3. Among the Inuit of Nunavik, the progressive increases in levels of EPA
and DHA in plasma phospholipids have been found in their dietary intakes
of these fatty acids. This is useful in lowering their risk for heart diseases.
How does Omega-3
Work?
Increasing the intake of EPA and DHA will
lead to an increase
of omega-3 fatty acids in tissue
or cellular lipids and circulatory lipids. At the same time, it
will reduce the omega-6 fatty acids such as LA and Arachidonic Acid (AA),
which is not beneficial to our bodies.
The fatty acid shifts are particularly pronounced in the cell membrane-bound
phospholipid components. These changed profiles alter the physicochemical
properties of:
· Cell membranes and their functioning, resulting in improved endothelial
function and reduced inflammatory response. There is also reduced platelet
aggregation and enhanced blood flow. The vasodilatory effect will increase
lumen size of vascular system. Studies have shown that fish oil concentrates
that provide EPA and DHA at intakes of up to 2-4g a day, taken over a few
weeks, can lower various risk factors for heart disease. These effects include
an antithrombotic effect, lipid (triglyceride) lowering, reduced blood and
plasma viscosity, and improvements in endothelial dysfunction.
Omega-3 fatty acids accumulate to a considerable extent in various sites
including circulating blood platelets, the heart and serum phospholipid.
The accumulation of EPA and DHA in platelets leads to a decrease in platelet
adhesiveness, aggregation and an overall reduction in thrombogenicity. Antiatherogenic
effects of omega-3 fatty acids have also been shown in animal studies with
similar results.
· Eicosanoid formations. The eicosanoids formed via oxygenase enzymes
acting on AA and EPA includes prostaglandins, leukotrienes and thromboxanes.
Both eicosanoid-dependent and eicosanoid-independent processes mediate the
benefits of omega-3 fatty acids on cardiovascular disease. For example,
the reduced blood platelet reactivity (antithrombotic effect) with increased
EPA and DHA intakes involve the reduced formation of the proaggregatory
eicosanoid known as thromboxane A2 (TxA2).
Statin Drugs
Patients undergoing statin therapy with
combined hyperlipidemia were given EPA and DHA supplements. The latter was
found to reduce levels of atherogenic lipoproteins while more effectively
reducing the hemostatic risk profile of the patients.
Taking
fish oil will save about 20 lives per 1,000 patients per year
when treated with omega-3.
How does this compare to statin drugs, you may ask? Well, in the Heart
Protection Study Collaborative Group (Lancet vol. 360, July 6, 2002), it
was shown that when 40 mg of simvistatin (a statin drug) is given to high-risk
patients, there is an overall savings of 179 lives out of the population
studied of 10,267 patients. This equates to 17 lives per 1,000 patients
per five year, or 3.6
lives per 1,000 patients per year with statin-type cholesterol lowering
drugs.
LOWER TRIGLYCERIDES
A study was carried out to assess the potent ability of EPA and DHA in reducing
circulating levels of blood triglyceride as only moderate elevations in
triglyceride have been associated with an increased risk of ischemic heart
disease. The people in this study were given EPA and DHA supplements orally.
Within 2-3 weeks, their blood
triglyceride levels fell by 6 to 8 percent per gram of EPA and DHA.
In a placebo-controlled, double-blind trial; postmenopausal women received
4 grams of omega-3 (EPA and DHA) daily over 28 days. Their blood triglyceride
level fell by 26 percent.
| Attention Because of tremendous individual variation, the use of nutritionals should therefore be personalized for your body. One person’s nutrient can be another person’s toxin. If you have a specific health concern and wish my personalized nutritional recommendation, write to me by clicking here. |
Anti-arrhythmic
The antiarrhythmic potential of EPA and DHA has been considered to be yet
another important mechanism in reducing deaths caused by heart disease.
In this case, patients only need to consume about 1 gram of EPA and DHA
per day to enjoy its benefits.
Irregular heart rate variability leads to an increased risk of coronary
heart disease, mortality and arrhythmic events. Studies have indicated that
consuming 4 grams per day of EPA and DHA can be of help.
Heart rate variability, a noninvasive marker of autonomic nervous system
function, is reduced with sympathetic predominance and other factors (including
reduced baroflex sensitivity) that may be favorably modified by omega-3
fatty acids.
Depression
Studies have shown that a daily dose of
1 gram of an omega-3 fatty acid for 12 weeks reduce symptoms of depression
such as hopelessness and sleeping problems. Taking omega-3 fatty acids is
helpful even for those who have been on other anti-depressant drugs such
as Zoloft or Prozac ( selective serotonin reuptake inhibitors (SSRIs). 69
percent of the patients achieved a 50 percent reduction in their symptoms,
in contrast to those who took placebos, where 25 percent of the patients
saw improvement. Interestingly, a high dose of 2-4 grams does not
correlate with more reduction in symptoms. This was reported in the
Archive of General Psychiatry ( Oct , 2002)
It is suggested that in depressed patients, the balance of omega-3 fatty
acids in the brain may become skewed , and earlier studies have shown that
fish oil supplements can help alleviate the symptoms of schizophrenia and
bipolar disorder, or manic depression.
WHAT ABOUT
ALA?
These are derived from plant foods and vegetable oils. For people who do
not consume fish, the omega-3 fatty acid known as ALA
can be a dietary source.
De-saturation plus elongation reactions in the liver provides for the conversion
of dietary ALA
to EPA and DHA.
The conversion of ALA to EPA and DHA occurs, to a low extent, in the adult
human body. Nonetheless, there is evidence that the benefits of the Mediterranean-type
diet after myocardial infarction may be caused by the higher intake of ALA.
This is commonly found in non-hydrogenated canola oil, ground flaxseed and
other selected ALA-enriched foods.
Many studies on this subject were carried out but with mixed results.
The Nurses Health Study revealed the higher the ALA intake, the lower the
risk of fatal ischemic heart disease among the women studied.
The Zutphen Elderly Study said that there were no benefits using dietary
ALA on the 10-year risk of coronary artery disease.
The metabolic conversion of ALA to the longer chain omega-3 fatty acids
(EPA and DHA) is thought to mediate possible cardio-protective effects of
dietary ALA. In contrast to the well-recognized serum triglyceride-lowering
effects of EPA and DHA, most studies with ALA
have not shown any lipid-lowering effects.
High dosages of ALA
have been found to improve arterial compliance, lower supplementation levels
of EPA and DHA, as well as improving arterial and endothelial functioning
in patients with hyper-cholesterolemia and type 2 diabetes mellitus.
Omega-3 also
has numerous other properties. It has been shown to:
· Inhibit cyclooxygenase 2,
which promotes mammary carcinogens and resulting breast cancer. (British
Journal of Nutrition 2002, March 87(3): 193-8).
· Aid inhibition of colonic PKCbeta 2 signaling and restoration of
TGF-beta responsiveness (J of Cell Biology 2002, Jun 10: 157(6): 915-20).
Colon cancer is reduced.
· Reduce the risk of prostate cancer (The Lancet 357: 9270; June
2001: 1764). In fact, those who have the highest fatty fish consumption
group had approximately ¼ rate of death from prostate cancer.
· Result in great reduction in the mean annual exacerbation rate
and the mean expanded disability status cycle of patient with multiple sclerosis
(Acta Neurol Scand 2000 Sept).
· Increase in lung function and reduction in asthma (Respiration
1998; 65(4).
· Sustained clinical improvement in symptoms of depression (Int J
Clint Pract 2001 Oct: 55(8).
· Reduction in dysmenorrhea and rheumatoid arthritis.
How Much
omega-3 in the diet?
· Eskimos take in 7-10 grams /day.
· Neo-Paleolithic hunters: 3 grams/ day.
· Current American intake is 0.12 grams/day.
This reflects the average daily intake of fish in the North American
diet of about one serving every 10 days or about 120 mg of DHA per day.
This is much lower than what the Japanese take in, and they have the highest
longevity record.
· American Heart Association Recommendation of 3 servings of fish per week
will give 500 mg/day. Fish consumed about 3 times a week would provide
a combined intake of about 500 mg EPA and DHA per day. A National Institutes
of Health workshop held in 1999 recommends a daily dosage of EPA and DHA
at 650 mg. This is about 4 times more than the current North American's
diet. Simply said, Americans are simply not eating enough fish.
Sources
of omega-3 in 4 ounces of the following are:
· Herring: 2.4 grams
· Mackerel: 2.1 grams
· Atlantic Salmon: 2.1 grams
· Pacific Oysters: 1.6 grams
· Pacific Salmon: 1.5 grams
· Trout: 1.1 grams
· Freshwater Bass: 0.9 gram
· Swordfish: 0.9 gram
· Canned tuna: 0.8 gram
· Halibut: 0.5 gram
· Snapper and shrimp: 0.4 gram
· Yellow fin tuna: 0.3 gram
· Catfish: 0.1 gram
· Fast food fish sandwich and wish sticks: essentially none
A normal North American diet contains
about 1-3 g of ALA
per day but only 100 to 150 mg of EPA plus DHA per day. The high intake
of n-6 PUFA derives mainly from vegetable oils such as corn and safflower
in the form of Linolenic acid (LA) in their diet (12-15 g/day).
Even though the American Heart
Association's (AHA) dietary guidelines recommend at least two servings of
fish per week, it is wise to keep in mind the recent Environmental Protection
Agency and Food and Drug Administration (FDA)'s warnings concerning the
possibility of contamination among certain species of fish. A report was
published to weigh the benefits and risks of consuming omega-3 fats from
fish. (Circulation November 19, 2002; 106(21): 2747-57).
The results of the studies revealed that the benefits and risks of consuming
omega-3 fatty acids from fish depend largely on an individual's life stage.
The
mercury that may be present in fish could have adverse effects on children
and women who are pregnant or nursing. Middle-aged and older men as well
as postmenopausal women are encouraged to consume more fish as the benefits
of eating fish are thought to outweigh the risks.
Regular fish consumption, up to 2-3 times a week, is beneficial
for healthy people as well as those with heart disease. However, how the
fish is prepared is also another consideration. Fried or processed fish
containing partially hydrogenated fats and salted or pickled fish should
be avoided.
Among patients with elevated triglyceride, which is an indicator
for heart disease, the statistics demonstrate positive effects from taking
2 to 4 grams of EPA and DHA per day as a form
of supplement. Daily supplements of 1 gram of EPA and DHA might
also benefit those with heart disease. However, according to the same report,
excessive intakes of EPA and DHA -- may result in prolonged and increased
bleeding in some people.
The amount of active ingredient to
take depends on your goals. Here are some guidelines:
· To maintain good health: 1.5 to 2.5 g / day
· Improve cardiovascular function: 2.5 to 5 g / day
· Improve brain function: 5 - 10 g / day
· Reduce inflammatory response: 5 -10 g / day
· Optimum health: 5 to 10 g / day
· Treatment of neurological diseases: > 10 g / day
| Attention Because of tremendous individual variation, the use of nutritionals should therefore be personalized for your body. One person’s nutrient can be another person’s toxin. If you have a specific health concern and wish my personalized nutritional recommendation, write to me by clicking here. |
The standard fish oil capsule contains
180 mg of EPA and 120 mg of DHA per 1000 mg capsule. If you are taking a
regular 1000 mg fish oil capsule, you are only getting about 300 mg of the
active ingredients EPA and DHA and not the 1.5 grams per day for optimum
health. Some people may not tolerate it as excessive fish oil produces
a harmless fishy smell.
Fortunately, some high grade fish oil capsules of 1000 mg now comes
with 360 mg EPA and 240 mg DHA. You need only to take 2 of such capsules
to derive 1.1 grams of EPA and DHA.
Cod liver oil, in addition to containing omega-3 fatty acids, also contains vitamin D. If you live in an area where sunshine is limited, cod liver oil may be a consideration. Otherwise, liquid fish oil is sufficient.
If you are looking to take high dosage of
fish oil (more than 3-5 grams) , then pharmaceutical grade liquid omega-3
fish oil is the best way to go and is recommended. Pharmaceutical grade
fish oil has some very distinct characteristics, including the following:
Concentration of EPA and DHA per mg of fish oil is equal or greater to 60%;
ratio of EPA to AA > 25:1; and concentration of PCBs < 10 ppb/g.
The raw material is much more expansive in such pharmaceutical grade fish
oil, and it therefore costs many times more than health-food grade fish
oils. If you look at the cost per mg of EPA and DHA, however, the
cost is actually comparable and you do not have to take as many capsules.
The
best grades can provide up to 1.8 grams EPA and 0.9 gram DHA per teaspoon.
Two
teaspoons per day will deliver 5.4 grams of active ingredients for therapeutic
nutrition, while one teaspoon per day is excellent for maintaining optimum
health.
If you are unable to take fish oil, consider flaxseed oil as an alternative. While flaxseed also contains DHA and EPA, the amount is much less. Flaxseed also has a tendency to rancid rapidly, so it is important to take it fresh.
Side Effects
A. Blood Thinner
Fish oil, in high doses, has a blood thinning effect. In a study published in the New England Journal of Medicine (1986 April 10; 314(15): 937-42), it was shown that 10 grams of EPA have the same bleeding time effect as a single 320 mg of aspirin. While some studies have point to a faster surgical recovery time when fish oil is taken in the peri-surgical period to boost immunity and wound healing. It is recommended for safety purposes that consumption of fish oil be stopped one week before any surgical procedure.
If you are already on blood thinners such as warfarin or aspirin or herbs such as gingko biloba or a high dose of vitamin E, consult your physician before taking fish oil as the blood thinning effect may be exacerbated.
B. Adult Onset Diabetes
Fish oil in high doses may also worsen adult onset diabetes mellitus. In one study conducted over a 6 week period, diabetic patients were given 4 grams per day of EPA, DHA or olive oil in addition to their regular diets. The results showed that compared with the olive oil, the EPA and DHA increased their blood sugar levels without a corresponding increase in insulin levels. The mechanism of action is still under investigation, but researchers postulated that the liver increased its production of glucose in the process of breaking down the increased levels EPA and DHA oils. Do not take high dose fish oil if you are a diabetic and have not yet consulted with your nutritionally oriented physician.
Contamination
Issues
Unfortunately, our fish is polluted with toxins like mercury and PCB. Cod liver oil as a source of omega-3 is no longer recommended. In addition, cod liver oil should not be taken if you already have significant sun exposure. You will run the risk of overdosing on vitamin D. Instead, fish oil capsules should be taken.
To overcome the metal toxicity problem,
you should consider oral chelation with EDTA which will bind many of the
toxic metals out of the gastrointestinal track.
While you can get fish oil from mass merchandisers such as Wal-Mart or Costco,
it is suggested that you should consider getting a better source of fish
oil. Don't
forget that you generally get what you pay for. Being
cholesterol free and processed by molecular distillation is the minimum
requirement. Some PCB's are removed, but not all in this process. The purest
pharmaceutical grade fish oil should contain less than 10 ppb of PCB/gram
of oil. The price is much higher, but worth considering if you are taking
high dosage (5 grams or higher per day).
Balance of Omega-3
to Omega-6 Fatty Acids
Studies have shown that our
diet contains far too much omega-6 fats.
The ratio of omega-6 fats to omega-3 fatty acids in early human history
was about 1:1.
This is the optimal ratio. Today,
the American's
dietary ratio falls between 20:1 and 50:1.
As such, they will have to reduce the omega-6 fatty acids and increase the
amount of omega-3 fatty acids taken in their diets.
The average American fast and processed
food diets contain sufficient amounts of omega-6 and omega-9 fatty acids.
Many of the omega fat
supplements in health food stores will worsen your health, as it will increase
your omega-6 to omega-3 ratio.
Oil containing sunflower, corn, soy, safflower and canola should be avoided.
This oil has a high proportion of omega-6 fats. We should use virgin olive
oil, coconut oil, avocados oil and organic butter instead.
Another way of improving your omega 6:3 ratio is to consume more game meat
like venison, or animals that have been raised exclusively on grass type
foods. However, these are hard
to find and generally more expensive than beef.
All cattle are grain fed before slaughtering. Therefore, consuming traditionally
raised beef will worsen your omega 6: omega 3 ratio. An ideal ratio of consuming
fish is 2 or 3 to 1 (The lower the better). A study conducted by Iowa
State
University in August 2001 reported that grass-fed beef is much higher in
Omega 3 fatty acids than fish.
To get the necessary Omega-3 fatty acids, one should consume meat that has
been allowed to "free-range" or in the case of cattle, to be grass-fed.
However, It is often very difficult to buy these from the local butcher.
Many stores may advertise grass-fed beef but it may not be genuine.
Although all cattle are initially grass fed, many of them are fed corn to
fatten them up a few months before they are slaughtered. Fortunately, grass
fed beef is now commonly available at heath food stores.
Another method is to purchase ground beef and simmer the beef slowly until
it is well cooked, drain and collect all the fat. Grass fed beef is very
high in omega-3 fats and will be relatively thin compared to traditionally
prepared ground beef.
| Message from Dr. Lam I hope you have enjoyed reading this article. If you have areas you don’t understand, comments (good or bad), or if you have a specific health concern, feel free to write to me by clicking here. |
About The Author
Michael Lam, M.D., M.P.H., A.B.A.A.M. is a specialist in Preventive and Anti-Aging Medicine. He is currently the Director of Medical Education at the Academy of Anti-Aging Research, U.S.A. He received his Bachelor of Science degree from Oregon State University, and his Doctor of Medicine degree from Loma Linda University School of Medicine, California. He also holds a Masters of Public Health degree and is Board Certification in Anti-aging Medicine by the American Board of Anti-Aging Medicine. Dr. Lam pioneered the formulation of the three clinical phases of aging as well as the concept of diagnosis and treatment of sub-clinical age related degenerative diseases to deter the aging process. Dr. Lam has been published extensively in this field. He is the author of The Five Proven Secrets to Longevity (available on-line). He also serves as editor of the Journal of Anti-Aging Research.
For More Information
For the latest anti-aging related health issues, visit Dr. Lam
at www.LamMD.com. Feel free to email
Dr. Lam at dr@LamMD.com if you have any questions.
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©2002 Michael Lam, M.D. All Rights Reserved.
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