2005-08-02
Richard Harkness - KNIGHT RIDDER NEWS SERVICE

QUESTION: I was told that flaxseed oil capsules were just as good as fish oil capsules because both contain the same omega-3 fatty acids. I take fish oil capsules to lower my triglycerides, but get a fishy aftertaste with them. Will switching to flaxseed oil capsules work OK?

ANSWER: The quick answer is no. Only fish oil appears to substantially lower blood levels of triglycerides.

What you were told is a common misconception. It's true that flaxseed oil and fish oil both contain omega-3 fatty acids, but there's an important difference between the two.

Fish oil contains the preformed omega-3 fatty acids EPA and DHA. Flaxseed oil, on the other hand, contains the omega-3 fatty acid called alpha-linolenic acid or ALA for short, which is the precursor of the omega-3 fatty acids present in fish oil.

The body can convert the ALA in flaxseed oil to EPA and DHA, but converted amounts seem to be minimal.

Though flaxseed oil is thought to be heart-healthy in its own right, you can't count on it as a substitute for fish oil.

There are two ways to increase your intake of fish oil omega-3 fatty acids: Eat fish or take a fish oil supplement.

Your fish menu could include cold-water fish such as salmon, tuna, mullet, herring, mackerel, sardine and lake trout.

Research suggests that fish oil cuts the risk of heart disease and is heart-protective in those who already have heart disease.

Fish oil's heart-healthy benefits appear to include lowering the heart rate, fighting inflammation, reducing blood clot formation and inhibiting plaque buildup in arteries.

Fish oil at a daily dose of 3 to 12 grams lowers triglyceride concentrations by 20 percent to 50 percent. Acids present in fish oil should hit pharmacy shelves soon. Called Omicor, it will be marketed for treating high triglycerides. The manufacturer also wants it approved for preventing recurrent heart attacks.

Omicor presents doctors with a new option for treating patients who have both high LDL-cholesterol and high triglycerides.

These individuals often require two drugs, generally a statin drug (Lipitor, Mevacor, Zocor, Lescol, Pravachol, Crestor) combined with a triglycerides-lowering drug (Lopid, TriCor, niacin).

But such drug combinations can boost the risk of a serious muscle-kidney disorder called rhabdomyolysis. Omicor appears not to carry this risk.

A caution: Fish oil in daily doses over 3 grams thins the blood. Combining it with blood-thinning drugs could increase the risk of excessive bleeding. These include aspirin, NSAIDs (e.g., ibuprofen, naproxen), clopidogrel (Plavix), dalteparin (Fragmin), enoxaparin (Lovenox), and warfarin (Coumadin). Blood-thinning supplements include garlic, ginkgo, phosphatidylserine, and high-dose vitamin E.

Richard Harkness is a consultant pharmacist and specialist in natural therapies. E-mail: rharkn@aol.com.