Omega-3 Fatty Acids

What They Are

This group of fatty acids, also known as fish oil, has gained popularity as a protective agent for the heart. Omega-3 supplements contain docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA).


What They Do

The omega-3 fatty acids are believed to lower the levels of triglycerides (fats) and total cholesterol in the blood, while raising the amount of HDL (good) cholesterol. These acids also discourage unwanted clotting that can aggravate plaque build-up.


Why You Need Them

In people with a cholesterol problem, omega-3 fatty acids can help prevent the build-up of cholesterol-laden plaque that can clog the arteries and lead to heart attack and stroke.


Can You Take Too Much? 

Because omega-3 fatty acids discourage clotting, excessive levels can lead to bleeding problems in case of an accident or trauma. Women who menstruate are also in greater danger of developing anemia.


Recommended Daily Allowances

There is no recommended dietary allowance (RDA) for the omega-3 fatty acids. To increase your intake of the omega-3 fatty acids, nutritionists generally recommend eating more fish (2 to 3 times a week), rather that taking large amounts of supplements. A 7-ounce serving of certain types of fish 1 easily provides 2 to 4 grams of omega-3 fatty acids.


Best Dietary Sources

The omega-3 fatty acids are found in cold-water fish. Best sources include cod, tuna 2, salmon, halibut, shark, and mackerel. Herring, bluefish, shrimp, flounder, and swordfish also provide good amounts of these acids. A 7-ounce portion of herring contains 3.2 grams of omega-3 fatty acids. The same serving of salmon or bluefish provides 2.4 grams. Seven ounces of tuna has 1 gram.


1) Isn't flax seed oil also a significant source?

2) Here it says that tuna is a “best” source, but it’s last on list of good sources.


Source: health.


Sources of Omega-3s

Here is a sampling of fish with the amount of omega-3 fatty acids each contains, according to the U.S. Department of Agriculture. Ranges given allow for variations in the diets of the fish.

Atlantic Salmon: 3.1 to 3.7 grams per 6-ounce cooked serving.
Sardines (packed in oil): 2.8 grams per 3-ounce serving.
Coho Salmon: 1.8 to 2.2 grams per 6-ounce cooked serving.
Kippered Herring: 1.8 grams per 3-ounce serving.
Rainbow Trout: 1.7 to 2 grams per 6-ounce cooked serving.
Swordfish: 1.4 grams per 6-ounce cooked serving.
Oysters: 1.1 grams per 3-ounce steamed serving.
Mackerel (canned): 1 gram per 3-ounce serving.
Sole or Flounder: 0.9 gram per 6-ounce cooked serving.
Striped Bass (Rockfish): 0.8 gram per 6-ounce cooked serving.
Tuna (white, canned): 0.7 gram per 3-ounce serving.
Tuna (fresh): 0.5 gram per 6-ounce cooked serving.


Source: Martha Stewart Living