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The Omega 3 Factor
Introduction
Several decades ago, physicians working in the Arctic noticed that the Inuit (Eskimo) people rarely developed
coronary heart disease, even though their diets, which consisted primarily of whale meat, seal meat, turbot and
char were high in fat and cholesterol. Epidermiological studies confirmed that coronary heart disease rates in
Canadian Inuit who consumed their traditional foods were much lower than those of Westerners. " This
difference wasn't due to the amount of fat in the diet; in fact, the amount of total fat in the Inuit diet is similar
to that of a Western-style diet. However, the source of fat in the two diets is different. Inuit get their fat almost exclusively from marine mammals and fish, while Westerners obtain their fat from land animals and
plants.
These early observations prompted extensive investigations of the possibility that some component of
seafood might be protective against coronary heart disease. Most of this research has focused on omega-3 (or
n-3) polyunsaturated fatty acids (PUFA), a distinctive type of fatty acid that is present in substantial amounts
in fish oils. The omega-3 PUFA have a variety of biological effects that may influence the risk of cardiovascular disease.
The Good Fat Fundamentals
To appreciate the distinctive nature of the fatty acids found in fish oils, it is necessary to understand some of
the terms that are used to describe and classify fats.
Fats are molecules that consist of three fatty acids chemically linked to an alcohol called glycerol. All fats contain
mixtures of different types of fatty acids. Fatty acids consist primarily of long linear chains of carbon atoms with hydrogen atoms bound to them.
The most prominent long-chain omega-3 PUFA in fish oils are eicosapentaenoic acid (EPA), which is 20 carbons long, with five double bonds (20:5,omega-3), and docosahexaenoic (DHA), which is 22 carbons long,
with six double bonds (22:6, omega-3). The richest dietary sources of EPA and DHA are fatty fish such as mackerel, herring, salmon and Greenland halibut (turbot). A second type is called omega-6. Monounsaturated
fatty acids are from the omega-9 family of fatty acids. We must obtain omega-3 and omega-6 fatty acids from the foods we eat.
There is a significant body of evidence that suggests that omega-3 fatty acids may play a role in reducing the
risk of heart disease, which is the leading cause of death in most Western countries. Researchers have found that omega-3 fatty acids can make blood less likely to clot and block blood vessels, and that consuming
omega-3s may also decrease levels of some blood fats and possibly cholesterol. Possible relationships between
omega-3 fatty acids and other disorders such as cancer, arthritis, and asthma are also currently being studied.
Omega-3 fatty acids are also critical components of the cell membranes of brain and eye tissues, and dietary sources of omega-3s are needed to ensure proper development of these organs.
Omega-3 fatty acids are found almost exclusively in aquatic organisms, and smaller amounts can be found in
some plants and plant oils. Seafood is considered to be the best dietary source of omega-3 fatty acids. All fish and shellfish contain some omega-3s but the amount can vary. Generally the fattier fish contain more
omega-3 fatty acids than the leaner fish, but the proportion of saturated, unsaturated and omega-3 fatty acids
can vary considerably from one species to another. The amount of omega-3 fatty acids in farm raised products
can also vary greatly depending on the diet that the fish or shellfish are fed. Many companies now recognize this fact, and provide a source of omega-3 fatty acids in their fish diets. The following table gives a comparison of the amount of omega-3 fatty acids in various types of fish and shellfish.
The beneficial effect on human health of the omega-3 fats found in seafood were among the topics explored
by more than 200 prominent doctors and health science professionals the conference on "Dietary Fatty Acids
and Cardiovascular Health." Despite unresolved issues in the scientific community about the role played by
specific fatty acids, the prevailing views reflect a shift in dietary goals from "low" to "moderate" fat
consumption. The basis for this shift is the widespread recognition, based on research, of the benefits of
unsaturated fatty acids. Among these are the omega-3 fats found in seafood, especially abundant in fatty fish such as turbot.
In a widely reported study that helps counteract the impact of methyl mercury stories, researchers at Harvard
have found that eating five portions of oily fish per week can cut the risk of having a stroke in half, according
to a newly published study. Researchers at Harvard University's Brigham and Women's Hospital tracked the eating habits and medical records of 79,839 women for 14 years. After taking age and smoking into account,
they found that women who ate five portions of oily fish each week cut their risk of having a stroke by 52 per cent.
The study also found that eating just one portion of oily fish a week cuts the risk by 22 per cent. According to
NMFS data, Americans eat only about 1.3 servings of any type of seafood each week, based on an average of 3.5 oz. per serving.
The study reports that oily fish like mackerel, salmon and Greenland halibut (turbot) contain omega-3 fatty
acids, which are known to have a number of health benefits. Among the health benefits are slowing the growth of tumors, easing arthritis and asthma, promoting fetal brain development, and boosting the
immune system. The study found that eating oily fish was particularly helpful in reducing thrombotic infarction, a type of stroke in which a blood clot blocks an artery in the brain, resulting in the death of brain
tissue. The Harvard study is one of the first to provide definitive proof of a protective role for fish in cardiovascular disease. The results were published in the Journal of the American Medical Association.
- Benefits
Omega-3 fish oil:
- Decreases triglycerides up to 30%
- Reduces blood clotting
- Lowers blood pressure
- Decreases blood viscosity
- Reduces the development of arrhythmia
- Lessens inflammation in the joints and muscles
- Increases natural levels of anti-inflammatory agents
- Reduces the risk of brain disorders
- Improves memory
- Enhances cognition, awareness and mood
Definitions and Difficulties
Omega 3 fatty acids are found predominately in fish oil and thousands of scientific publications highlight their
role as essential nutrients with versatile health benefits. The Omega 3 Factor is a simple but incompletely understood hypothesis. It draws attention to the widespread deficiency of omega 3 fatty acids worldwide and
highlights the potential importance of these fatty acids in preventing, treating and perhaps even reserving
common crippling or killer diseases. Not only is the hypothesis incomplete, it is not novel or new. Incomplete knowledge of the role of essential fatty acids and their role in the promotion of wellness (or perhaps
disturbance in their balance in the promotion of ill health) leaves the hypothesis open to question and debate. The importance of the Omega 3 Factor as a hypothesis goes beyond the importance of fish oil or dietary
supplements that contain essential fatty acids because it is consistent with the modern call to be more restrictive with animal sources of food and more conscious of vegetable sources of food.
The Omega 3 Factor: Defined With Difficulty
- Simply, and perhaps naively stated, the hypothesis of the Omega 3 Factor can be summarized in the
following statements:
--- Omega 3 fatty acids are essential in the diet
Common dietary deficiency of omega 3 fatty acids (found predominately in fish oil) This "deficiency
status" of omega 3 fatty acids is amenable to supplementation with omega 3 fatty acids found in fish oil and it requires dietary changes
- Forgetting Essential Fatty Acids
The term fatty acid is not generally as endearing as the term vitamin or essential nutrient. The
shunning of the terms "fat" or "fatty" should not overshadow the clear recognition that essential fatty
acids are equally as essential as vitamins and other obligatory nutrients. Without essential fatty acids, many body functions will fail. For example, the brain will not grow, nerves will not function, blood
will not flow and essential aspects of life will fail.
- Understanding Fats and Fatty Acids
Fat is regarded as a dirty word by many health conscious individuals. This unfortunate assumption
overlooks the importance of essential fats as health giving nutrients and has led to a modern dietary deficiency state that has passed unrecognized by many. The role of a diet that is high in saturated fat in
the causation of a variety of common killer diseases is quite clear, but the role of fats in the promotion
of health is still clouded. Indeed, there are many fats that cause ill health but equally there are dietary fats that are obligatory to promote good health. The negative health connotation of excessive dietary
fat has overshadowed the importance of the more "healthy types" of fat in disease prevention or cure.
While saturated fat of animal origin is associated with cardiovascular disease and colon cancer, certain types of unsaturated fats are associated with the prevention of cardiovascular disease and cancer. This is
poorly understood.
Omega 3 fatty acids are relatively confined to marine sources. Omega 3 fatty acids are found largely in fish and marine mammals.
- What Do Fatty Acids Do?
Fatty acids are a very efficient source of energy for the body. One gram of fat contains more energy than
one gram of carbohydrates or protein. About nine calories of energy are derived from the body "burning" one gram of fat, whereas only five calories come from the "burning" of one gram of
carbohydrates. The term essential fatty acid implies that the fatty acid cannot be manufactured by the human body and it must be ingested in the diet. If an essential fatty acid is not consumed in the diet
deficiency will ensue in exactly the same way when vitamin or other obligatory nutrient deficiency occurs in the unbalanced diet.
The omega 3 family of fatty acids include alpha-linolenic acid (LNA), stearidonic acid (SDA), EPA and DHA are found only in oils of marine origin, such as those obtained from cold water fish and marine
mammals.
- Tracing the Origin of the Health Benefit of Fish Oils
There are many examples of differences in disease profile between races. Several factors may account for
these differences including environmental factors, diet, and genetic differences. The health benefit of fish oils has been recognized for many centuries. Many children in the past two centuries have choked
on the end of a teaspoonful of cod liver oil. Why did grandmother think that cod liver oil was healthy for a child?
The answer rests in part in studies of the disease profile of races that ingest large quantities of omega 3
fatty acids in fish oil. For example, Eskimo populations living under traditional conditions have a very high consumption of fat and protein in the diet, but a remarkably low incidence of cardiovascular
disease. The Inuit language of the Eskimo contains more than 40 words to refer to snow, but there is no word in this native tongue to describe heart disease. It is of interest that the term Inuit means
"eaters of raw meat". Inuit or Eskimos (natives of Greenland) in their natural habitat live largely upon both raw and cooked flesh and fat derived from fish or marine mammals, such as seals. Marine
mammals and fish of cold water origin are the most abundant source of omega 3 fatty acids in the form of EPA and DHA.
The Eskimo rarely dies of cardiovascular disease, despite the high fat, high cholesterol, low carbohydrate diet that typifies their existence in their native habitat. There is a number of other
differences in disease profile between the Eskimo and members of Western society which include a relatively low prevalence of inflammatory bowel disease and other degenerative disorders.
Unfortunately, modern data on the epidemiology of disease in Inuit population shows a shift away from the low incidence of such disease states, including cardiovascular disease as this population of
individuals adopts a Western diet. At present, alarming data exists that substance abuse is very common among the Inuit. Lifestyle factors, together with a change in the Inuit diet towards more
Western foods, which tend to include large amounts of saturated fat, the disease profile of the urbanized Inuit resembles that of the Westerner. This is one of several examples where modern
"Western influences" play a major role in altering morbidity and mortality profiles among several races.
The Eskimo or Inuit who has a traditional diet based on fish or marine mammal products has a
lower incidence of autoimmune disease, asthma, scorosis, and chronic inflammatory disorders. One very interesting observation is the lack of occurrence of diabetes malitis among Eskimos and Inuit
who take a traditional diet containing fish oil.
- Essential Fatty Acids; The Important Health Link
Omega 3 fatty acids, EPA and DHA (which are present in fish oil), when supplemented in the diet,
may have the ability to reduce blood cholesterol and induce beneficial changes in other blood lipids such as lowering triglycerides, reducing levels of LDL and VDL, together with increases in HDL have
been well documented. Several studies have shown that long-term dietary supplementation with fish oils may exert beneficial effects on blood lipids and cardiovascular disease. Beneficial effects on blood
lipids have been observed in cases of high blood cholesterol in patients with high blood triglycerides. This observation implies that fish oils may be beneficial in protecting against rises in blood cholesterol
from normal dietary intake of cholesterol. Overall, a large body of evidence exists to show a beneficial effect of fish oils on blood cholesterol
A number of researchers have found that fish oil supplementation of the diet tends to result in a decrease of blood viscosity and a corresponding increase in the ability of red blood cells to undertake
deformation. Again, the common thread of those individuals with the highest blood viscosity will tend to have the greatest reduction in viscosity and these effects may be dose dependent.
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A COMPARATIVE VIEW OF OMEGA 3 FATTY ACIDS IN FISH
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(more than 1.0 grams) per 3 ounces
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(0.5 to 0.9 grams)
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(less than 0.5 grams)
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Turbot
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Scallops
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Carp
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Salmon
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Crab
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Cod
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Herring mackerel sardines
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Shrimp
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Grouper
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Atlantic bluefish
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Sea bass
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Pacific halibut
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Most shellfish
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Snapper
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Ocean perch
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Pacific oysters
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Clams
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Mahi mahi
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Squid
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Lobster
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Orange roughy
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Anchovy
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Striped bass
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Shark
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Mussels
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Rainbow trout
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At last, a food we should eat more of instead of less! Seafood is high in
protein and most varieties are low in fat. Contact Great Northern Products for your Seafood containing omega-3 fatty acids.
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Source materials:
The following sources among many other reference guides were utilized to produce this article. The views
expressed in this article do not necessarily reflect the official position of Great Northern Products Ltd but are
offered solely as a guide to be utilized in order to base some opinion about the benefits of omega-3's on the human body. Should you require further information, please contact omega3@northernproducts.com with any questions or comments.
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