Will the real omega-3 please stand up?

Health Professional

Walking the supermarket aisles, you may have noticed lately that many products are now sporting "omega-3s" on the label.

Omega-3 fatty acids serve a number of important health purposes, including reduction in heart attack and stroke, reduction of triglycerides, anti-inflammatory effects, and other significant health benefits. In the 11,000-participant Italian GISSI-Prevenzione Trial, for instance, death from heart disease was reduced an unprecedented 45% when participants took 850 mg of the omega-3 fatty acids, EPA and DHA, every day. We're not just talking about lower cholesterol or feeling better. We're talking about big, life-saving benefits.

So, just how much truth is there in the proliferation of products boasting this omega-3 claim?

Some products contain alpha-linolenic acid, a tiny amount of which is converted to the biologically active omega-3s, EPA and DHA. One bagel manufacturer, for instance, carries a claim of "620 mg omega-3s" prominently on the label. It contains no EPA or DHA, only linolenic acid.

I find this confusing and misleading, since people will often interpret such a claim to mean that it contains 620 of EPA and DHA, similar to two capsules of standard fish oil (1000 mg capsules containing 300 mg EPA and DHA in each capsule). Of course, the bagels do NOT. I find this especially troublesome when people stop or reduce their intake of fish or fish oil, since they've been misled into thinking that products like this bagel contain active omega-3 fatty acids that yield all the benefits of the "real stuff."

Other products actually contain the omega-3, DHA, though usually in small quantities. One popular brand of yogurt boasting the omega-3 claim contains DHA, for example, with 32 mg DHA per container.

I find products with actual DHA (from algae) a more credible claim. However, even this claim is not entirely straightforward. The Center for Science in the Public Interest (CSPI) has looked at the actual contents of DHA in these products and found some discrepancies, including amounts of DHA less than the labeled amount and claims of omega-3 without specifying DHA vs. linolenic acid. (It's probably linolenic acid, if it's not specified.)

All in all, the addition of DHA to food products is a nice way to boost your intake of this healthy omega-3. However, keep in mind that these are processed, often highly processed, foods and you will likely pay a premium for the little boost.

In my view, if you'd like the enormous life-saving benefits of omega-3 fatty acids, don't look for it in bagels, breads, or yogurt. Stick to fish oil, the real thing.

(For a brief summary of the CSPI report and a link to the Nutrition Action Newsletter, see Omega-3 Madness: Fish Oil or Snake Oil.)

Does it really matter?

Phyllis is the survivor of a large heart attack (an "anterior" myocardial infarction involving the front of the heart) several years ago. Excessive fatigue following the heart attack prompted a stress test, which showed poor blood flow in areas outside the heart attack zone. This led to a heart catheterization, then a bypass operation one year ago.

When I met her, Phyllis' triglycerides ranged from 200-300 mg/dl, suggesting that it was a factor contributing to her heart disease. Fish oil was the solution of choice, since it is marvelously effective for reducing triglycerides. Her dose: 6000 mg of a standard 1000 mg capsule (6 capsules) to provide 1800 mg EPA + DHA, the effective omega-3 fatty acids. Triglycerides dropped to 77 mg/dl.

But Phyllis is not terribly good at following advice. She likes to wander off and follow her own path. She noticed that the healthy bread sold at the grocery store and containing flaxseed boasted "900 mg of omega-3s per slice" So she ate two slices of the flaxseed-containing bread per day and dropped the fish oil.

Guess what? Triglycerides promptly rebounded to 290 mg/dl. She also gained 8 lbs. (though we can't blame only the bread, since Phyllis has a terrible sweet tooth.)

A more obvious example of the power of omega-3s occurs in people with a disorder called "familial hypertriglyceridemia," an inherited inability to clear triglycerides from the blood. These people have triglycerides of 400 mg/dl, 700 mg/dl, or higher. Fish oil yields dramatic triglyceride drops of hundreds of milligrams. Fish oil likely achieves this effect by activating the enzyme, lipoprotein lipase, that is responsible for clearing blood triglycerides. Flaxseed oil and other _linolenic acid _ sources yield . .. nothing.

Don't get me wrong: Flaxseed is a great food. As the ground seed, it reduces LDL cholesterol, reduces blood sugar, provides fiber for colon health, and may even yield anti-cancer benefits. Flaxseed oil is a wonderful oil, rich in monounsaturates, low in saturates, and rich in linolenic acid, an oil fraction that may provides heart benefits a la the Mediterranean diet.

But linolenic acid from flaxseed is not the same as EPA + DHA from fish oil. This is most graphically proven by the lack of any triglyceride-reducing effects of flaxseed preparations.

Enjoy your flaxseed oil and ground flaxseed-but don't stop your fish oil because of it. Heart disease and coronary plaque are serious business. You need serious tools to combat and control them. Fish oil is serious business for triglycerides. Flaxseed is not.