Omega-3 fatty
acids are a form of polyunsaturated fats, one of four basic
types of fat that the body derives from food. (Cholesterol,
saturated fat, and monounsaturated fat are the others.) All
polyunsaturated fats, including the omega-3s, are increasingly
recognized as important to human health.
Eating too
many foods rich in saturated fats has been associated with the
development of degenerative diseases, including heart disease
and even cancer. Polyunsaturated fatty acids, however, are
actually good for you. Omega-3s (found primarily in cold-water
fish) fall into this category, along with omega-6s, another type
of polyunsaturated fatty acids found in grains, most plant-based
oils, poultry, and eggs.
Why
"essential?" Omega-3s (and omega-6s) are termed
essential fatty acids (EFAs) because they are critical for good
health. However, the body cannot make them on its own. For this
reason, omega-3s must be obtained from food, thus making outside
sources of these fats "essential." Although the body
needs both omega-3s and omega-6s to thrive, most people consume
far more 6s than 3s. Hardly a day goes by, however, without
reports of another health benefit associated with omega-3s. For
this reason, many experts recommend consuming a better balance
these two EFAs. Different types of omega-3s. Key omega-3 fatty
acids include eicosapentaenoic acid (EPA) and docosahexanoic
acid (DHA), both found primarily in oily cold-water fish such as
tuna, salmon, and mackerel. Aside from fresh seaweed, a staple
of many cultures, plant foods rarely contain EPA or DHA.
However, a
third omega-3, called alpha-linolenic acid (ALA), is found
primarily in dark green leafy vegetables, flaxseed oils, and
certain vegetable oils. Although ALA has different effects on
the body than EPA and DHA do, the body has enzymes that can
convert ALA to EPA. All three are important to human health.
Health
Benefits
Scientists
made one of the first associations between omega-3s and human
health while studying the Inuit (Eskimo) people of Greenland in
the 1970s. As a group, the Inuit suffered far less from certain
diseases (coronary heart disease, rheumatoid arthritis, diabetes
mellitus, psoriasis) than their European counterparts. Yet their
diet was very high in fat from eating whale, seal, and salmon.
Eventually researchers realized that these foods were all rich
in omega-3 fatty acids, which provided real disease-countering
benefits.
Researchers
continue to explore this exciting field. They've found that
without a sufficient supply of polyunsaturated omega-3s, the
body will use saturated fat to construct cell membranes. The
resulting cell membranes, however, are less elastic, a situation
that can have a negative effect on the heart because it makes it
harder to return to a resting state.
In addition,
nutritionists have come to recognize the importance of balancing
omega-3 fatty acids with omega-6 fatty acids in the diet.
Because most people on a typical Western diet consume far more
omega-6-rich foods (including cereals, whole-grain bread, baked
goods, fried foods, margarine, and others), the ratio is out of
balance for almost everyone. This means for most Americans the
emphasis now needs to be on increasing omega-3s to make the
ratio more even.
The bottom
line: Omega-3s appear to help prevent and treat various
disorders in different ways. For example, research suggests that
in individuals with non-insulin-dependent (or type 2) diabetes,
omega-3s can improve insulin sensitivity. They work yet another
way to ease menstrual pain, and so on.
Specifically,
omega-3s in fish oil or other forms may help to
1. Improve
heart health. Omega-3 fatty acids have been shown to play a part
in keeping cholesterol levels low, stabilizing irregular heart
beat (arrhythmia), and reducing blood pressure. Researchers now
believe that alpha-linolenic acid (ALA), one of the omega-3s, is
particularly beneficial for protecting against heart and vessel
disease, and for lowering cholesterol and triglyceride levels.
An excellent source of ALA is flaxseed oil, sold as both a
liquid oil and a semisolid margarine-like spread.
Omega-3 fatty
acids are also natural blood thinners, reducing the
"stickiness" of blood cells (called platelet
aggregation), which can lead to such complications as blood
clots and stroke.
2. Reduce
hypertension. Studies of large groups of people have found that
the more omega-3 fatty acids people consume, the lower their
overall blood pressure level is. This was the case with the
Greenland Eskimos who ate a lot of oily, cold-water fish, for
example.
3. Improve
rheumatoid arthritis, lupus, Raynaud's disease, and other
autoimmune diseases. Diets high in omega-3 fatty acids (such as
fish oils) have been shown to increase survival in people with
autoimmune diseases. This is probably because the omega-3s help
the arteries--as well as many other parts of the body--stay
inflammation free. EPA and DHA are successful at this because
they can be converted into natural anti-inflammatory substances
called prostaglandins and leukotrienes, compounds that help
decrease inflammation and pain.
In numerous
studies over the years, participants with inflammatory diseases
have reported less joint stiffness, swelling, tenderness, and
overall fatigue when taking omega-3s.
In 1998, an
exciting review of well-designed, randomized clinical trials
reported that omega-3 fatty acids were more successful than a
placebo ("dummy drug") in improving the condition of
people with rheumatoid arthritis. The research also showed that
getting more omega-3 fatty acids enabled some participants to
reduce their use of nonsteroidal anti-inflammatory drugs (NSAIDs).
4. Improve
depression and symptoms of other mental health problems. The
brain is remarkably fatty: In fact, this organ is 60% fat and
needs omega-3s to function properly. Now researchers have
discovered a link between mood disorders and the presence of low
concentrations of omega-3 fatty acids in the body.
Apparently,
omega-3s help regulate mental health problems because they
enhance the ability of brain-cell receptors to comprehend
mood-related signals from other neurons in the brain. In other
words, the omega-3s are believed to help keep the brain's entire
traffic pattern of thoughts, reactions, and reflexes running
smoothly and efficiently.
Clinical
trials are underway to further investigate whether supplementing
the diet with omega-3s will reduce the severity of such
psychiatric problems as mild to moderate depression, dementia,
bipolar disorder, and schizophrenia. Interestingly, the oil used
to help the child with a degenerative nerve disorder in the
popular film Lorenzo's Oil was an omega-3 fatty acid.
5. Aid cancer
prevention and cancer support. Preliminary research from the
University of California, Los Angeles, suggests that omega-3
fatty acids may help maintain healthy breast tissue and prevent
breast cancer. Also, in a recent study, participants who
supplemented their diet with fish oils produced fewer quantities
of a carcinogen associated with colon cancer than did a placebo
group. More research into this exciting use for omega-3s is
underway.
Dosage
Information
There is no
established recommended daily intake for omega-3s, but a healthy
diet containing significant amounts of foods rich in this
essential fatty acid is clearly wise. By increasing your intake
of omega-3 fatty acids, you will naturally bring the ratio of
omega-3 and omega-6 fatty acids back into a healthier, 2-1 or
(optimally) 1-1 balance.
Try to reduce
your consumption of omega-6-rich foods at the same time that you
increase your intake of omega-3-rich foods in the following
categories:
Marine
sources: Atlantic salmon and other fatty, preferably cold-water
fish, including herring (both Atlantic and Pacific), sardines,
Atlantic halibut, bluefish, tuna, and Atlantic mackerel (All
wild not farm raised). Farm raised fish has more omega-6. The
American Heart Association recommends that people eat tuna or
salmon at least twice a week.
As a
reasonable substitute (or even an occasional alternative) for
fresh fish, commercial fish oil capsules are available
containing omega-3s such as DHA and EPA.
--Wild game:
Surprisingly, venison and buffalo are both good sources of
omega-3s and make a healthy choice for people craving meat.
These wild game meats can be purchased through mail-order
sources if your supermarket doesn't carry them.
--Plant
sources: walnuts, and leafy green vegetables such as purslane
are all good sources of alpha-linolenic acid (ALA), the
plant-based omega-3. A quarter-cup (1 ounce) of walnuts supplies
about 2 grams of plant-based omega-3 fatty acids, slightly more
than is found in 3 ounces of salmon. Whole health MD's extensive
Healing Kitchen provides details on the nutrients in many of
these foods, as well as recipes to include in your diet.
--Enhanced
food: In the U.S., these include omega-3 enriched eggs; breads
are sometimes enhanced in other countries.
Guidelines
for Use
Pregnant
women and infants need plenty of omega-3s to nourish the
developing brain of the fetus and young child. If a pregnant
woman gets too few omega-3s, the growing fetus will take all
that's available. This could set the stage for depression in the
mother. Talk to your obstetrician and pediatrician about
specific requirements.
General
Interaction
There are no
known drug or nutrient interactions associated with increased
consumption of omega-3 fatty acids through foods. However, if
you decide to take omega-3s through supplements (especially
those containing fish oils), be sure to check with your doctor
first if you are taking a blood-thinner such as warfarin or
heparin.
Possible Side
Effects
There are no
known side effects associated with increasing your intake of
omega-3 fatty acids through foods, although fish oil capsules do
pose the risk of a "burp" factor. This is a harmless,
although not exactly pleasant, fish-y aftertaste that occurs
with some brands of fish oil capsules.
Cautions
One benefit
of omega-3 fatty acids is that they are very safe to consume.
However, most sources recommend that fish consumption be limited
to two to three servings weekly because so many fish are tainted
with mercury and other contaminants. Fish oil capsules don't
present this same risk.
