Omega-3 Fatty Acids
What Are They?
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
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.
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.
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
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:
- 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.
- 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,
- 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
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.
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.
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.
- 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.
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)
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
- 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.
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 containingomega-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: Canola oil, flaxseed, flaxseed oil, 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.
WholehealthMD'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.
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.
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.