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Omega-3s: What You Need to Know
From Dr. Andrew Weil's Self Healing
http://www.drweilselfhealing.com/print_friendly.asp?iDocumentI D=156&iBDC=1872 It's not exactly news that most Americans eat too much fat and need to cut back on saturated and trans fats. But there's at least one kind of fat that we don't get enough of. We
should be eating more omega-3 fatty acids, which can offer a tremendous range of health benefits and are found in oily fish (like salmon and sardines) and certain nuts, seeds, and oils. Below are three points to know
about these good fats:
- Omega-3s are necessary for optimum health.
Omega-3s are called "essential fatty acids" because they can't be manufactured by the body and must come from the diet. They are important components of cell membranes, particularly in the brain and eyes. Also, the body uses omega-3s to make hormones that keep blood from clotting abnormally and inflammation from getting out of control.
- Omega-3s may benefit many health problems.
Studies have linked omega-3s from fish and other foods with a reduced risk of heart attacks and stroke, macular degeneration (a leading cause of blindness in older people), and various types of cancer, including breast, prostate, and colon. Countries with high fish consumption have the lowest rates of major depression and postpartum depression, and preliminary studies suggest omega-3 supplements may be useful adjuncts to conventional medications for treating bipolar disorder (manic depression) and schizophrenia. Omega-3 supplements have also proven helpful in reducing symptoms of inflammatory and autoimmune disorders such as asthma, rheumatoid arthritis, lupus, and inflammatory bowel disease. Diets rich in omega-3s can decrease insulin resistance in diabetics. And scientists suspect a lack of omega-3s may increase the risk of Alzheimer's and Parkinson's disease.
- The typical American diet is deficient in omega-3s.
The best food sources of omega-3s don't feature prominently in the modern Western diet. In contrast, some health benefits of the traditional Japanese diet and the Mediterranean diet may come from foods containing these good fats. Meanwhile, our diet now provides a large excess of another type of essential fatty acids, called omega-6s, primarily from polyunsaturated vegetable oils (corn, safflower, sunflower). While some scientists believe we need omega-6s and omega-3s at a ratio of about 2:1 or ideally 1:1 to keep vital body functions in balance, the ratio in the typical American diet is more like 10:1. This imbalance may increase risks of inflammatory disorders, heart disease, cancer, and other conditions. For this reason, I advise cutting back on omega-6s while increasing omega-3s.
Stocking Your Diet with Omega-3s How can you get optimal levels of omega-3s? Kathleen Johnson, a nutritionist who teaches at the Program in Integrative Medicine, advises most people to eat three
or more 3-ounce servings of oily fish (such as salmon or sardines) a week, plus another source of omega-3s (such as
walnuts or flax seeds) on other days. For vegetarians, she suggests eating 2 tablespoons of ground
flax seeds a day plus other omega-3 sources regularly. While these recommendations may seem high, you can work your way up to them gradually. Here's a rundown of foods rich in omega-3s:
Oily, cold-water fish.
Salmon (especially wild salmon), sardines, mackerel, and herring are the best sources of the long-chain omega-3s called DHA (docosahexaenoic acid) and EPA (eicosapentaenoic acid). DHA may offer specific benefits to the nervous system, while EPA is better known for its heart-protective effects. Your body can make these nutrients from the omega-3 fatty acid found in plant foods, called LNA (alpha-linolenic acid), but the conversion is often inefficient, especially if you consume a lot of omega-6s. That's why I think it may be better to eat fish rather than relying solely on plant sources of omega-3s.
Walnuts.
Nuts in general are heart healthy, and walnuts may be particularly helpful because they're a good source of LNA. Snack on raw walnuts or add them to salads. Another way to enjoy walnuts is to use walnut oil in salad dressing.
Flax seeds.
These are rich in LNA. Buy whole flax seeds at a health food store, store them in the refrigerator, and grind a half-cup at a time in a coffee grinder. Ground flax has a nutty flavor and tastes great sprinkled over cereals, salads, and baked potatoes. You can also bake flax meal into muffins or bread, which won't affect the omega-3 content, but heating flax makes it more susceptible to spoilage. Refrigerate flax meal in an airtight, opaque container for up to 30 days.
Hemp seeds.
Another good source of LNA is hemp seeds, which aren't psychoactive. Snack on toasted seeds or shelled seeds, which you can eat right from the bag or toast yourself. One company that sells hemp seeds is The Ohio Hempery:
(800) 289-4367 or http://www.buy-hemp.com/. Canola oil.
While I use olive oil as my main cooking fat, I occasionally use canola oil, a monounsaturated fat that also contains some LNA. Buy organic, expeller-pressed brands sold in health food stores and some supermarkets.
Fortified eggs. Several companies now sell eggs that contain omega-3s as a result of special mash fed to the hens. But you'd have to eat several eggs each day and take in too much cholesterol to get optimal levels of
omega-3s from eggs alone. What about Supplements? In general, I don't recommend supplementing with fish-oil capsules or flaxseed oil, available in capsules or liquid form, since the
food sources of omega-3s may contain other nutrients not found in the extracted oils. That being said, Kathleen Johnson suggests that people with autoimmune or inflammatory conditions, heart disease, mental or emotional
disorders, diabetes, and insulin resistance may benefit from taking fish-oil capsules or flax oil in addition
to getting omega-3s from their daily diet. Although taking omega-3 supplements may help lessen your symptoms, continue with any medications or other treatments needed for your condition. The omega-3
content of fish-oil capsules varies widely from product to product. So make sure you don't have to take too many capsules to get a daily dose of at least 1,000 mg of EPA and DHA combined for the above conditions. One
exception is bipolar disorder: The only published study used nearly 10 grams per day. A high-potency product that Johnson likes is Ultimate Omega EPA Formula from Nordic Naturals, which contains both EPA and DHA. It's
distilled for purity, and she claims that it doesn't cause you to burp up a fishy taste. To order, call (800) 662-2544 or visit http://www.nordicnaturals.com/. Fish-oil capsules may affect blood clotting, so it's best to avoid
them if you're taking anticoagulant drugs, have had a hemorrhagic stroke, or need surgery. If you wish to supplement with flax oil instead, use the liquid form, rather than taking lots of flax-oil
capsules. The suggested dose for the above conditions is 1 tablespoon each day, providing 7 to 8 grams of LNA. Look for flax oil in refrigerated sections of health food stores. Flax oil spoils easily, so don't use it if
it tastes like oil paint. Johnson says the flax oil from Spectrum Essentials is less prone to rancidity. Flax oil appears safe for women, but its safety for men is still unclear: Lab studies suggest it may increase the
growth of human prostate-cancer cells, but these findings haven't been confirmed in a clinical trial. (Flax seeds are fine for men.) Finally, I agree with Johnson that pregnant and lactating women may benefit
from supplementing with DHA (needed by the child for optimal cognitive and visual development) in addition to eating oily fish. One brand sold in many health food stores is Neuromins, derived from algae; follow package
directions. Also, I'm delighted that infant formulas enriched with fatty acids such as DHA may be available shortly. Omega-3 Fatty Acids and Heart Health from NORDICNATURALS Studies show that
populations who eat fish versus those who do not have a reduced death rate from cardiovascular disease. Experimental studies have shown that omega-3 fatty acids affect the function of cells involved in atherothrombosis
in numerous ways, including the modification of eicosanoid products in the cyclooxygenase and lipoxygenase pathways, the reduced synthesis of cytokines and platelet-derived growth factor, and alterations of leukocyte
and endothelial cell properties. Intervention studies in patients with restenosis, myocardial infarction, and cardiac arrhythmias with omega-3 fatty acid supplementation have been addressed in several clinical studies.
The ingestion of omega-3 fatty acids following one episode of myocardial infarction appears to decrease the rate of cardiac death. These effects of omega-3 fatty acids appear to be due to their
antiarrhythmic properties. In fact, fish oil has been shown to reduce ventricular arrhythmias and to be more beneficial than currently used pharmacologic agents. The dose, duration, and mechanisms involved in the
prevention and management of cardiovascular disease following omega-3 fatty acid ingestion or supplementation need to be investigated by double blind controlled clinical trials. Simopoulos AP; Omega-3
fatty acids in the prevention-management of cardiovascular disease. Can J Physiol Pharmacol Volume 75 Issue 3. Auth. Addr.: Center for Genetics, Nutrition and Health, Washington, DC 20009, USA.
Researchers at the Veterans Affairs Medical Center report that docosapentaenoic acid (DPA) and docosahexaenoic acid (DHA), a primary component of fish oil, provide significant protection against the development of
coronary heart disease (CHD). Their study involved over 6,000 middle-aged men who had samples of their blood taken between 1973 and 1976. During the next seven years, 94 of these men had a heart attack or died suddenly
due to heart disease. The 94 men were matched with 94 healthy men and the fatty acid profile of their blood samples compared. The researchers found that the 94 men with heart disease tended to have a higher serum level
of the saturated fatty acid palmitic acid and conclude that a high level of this acid increases the risk of CHD by 68 per cent. Palmitic acid is the main saturated fatty acid in most diets. This acid is known to cause
an increase in both total cholesterol and low-density cholesterol levels; the researchers, however, found that the detrimental effect of a high intake of palmitic acid persisted even after allowing for its cholesterol-
increasing effect. The researchers also determined that men with a higher blood level of the omega-3 unsaturated fatty acids, docosapentaenoic acid and docosahexaenoic acid had an almost 50 per cent lower risk of
developing heart disease than did men with lower levels. The researchers also found that men with CHD tended to have a higher serum level of omega-6 fatty acids derived from linoleic acid, but were unable to confirm
previous reports that these acids are linked to an increased risk of CHD. Simon, Joel A., et al. Serum fatty acids and the risk of coronary heart disease. American Journal of Epidemiology, Vol. 142,
No. 5, September 1, 1995, pp. 469-76 Fish oils and atherosclerosis
A recent study has investigated the beneficial effects of fish oil supplementation and atherosclerosis. A randomized,
double-blind, placebo-controlled clinical trial involved 162 patients with confirmed atherosclerosis. Half the patients were given 6 grams of fish oils per day for three months while the other half were given 6 grams
per day of placebo capsules containing a fatty acid composition resembling that of the average European diet. After three months the dosages were reduced to 3 grams/day for a further 21 months. Angiograms were taken at
the start of the trial and at the end of the two-year study period. At the end of the treatment twice as many of the patients in the fish oil group (16) showed regression of their atherosclerotic deposits when compared
to the placebo group. Three patients in the placebo group suffered a non-fatal heart attack during the 2-year period as compared to only one in the fish oil group. Seven patients in the placebo group had a
cardiovascular event (heart attack or stroke) as compared to only two in the fish oil group. The researchers conclude that fish oil supplementation may be beneficial for atherosclerosis patients and is safe and
well-tolerated. von Schacky, Clemens, et al. The effect of dietary omega-3 fatty acids on coronary atherosclerosis.
Annals of Internal Medicine, Vol. 130, April 6, 1999, pp. 554-62 Co sponsor:Pronova A.S *These statements have not been evaluated by the Food and Drug Administration. This product is not intended to
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