Finally, you can know for sure if you’re getting enough omega-3s

The positive research just keeps on coming. First, scientists told us that omega-3 fatty acids help guard against heart disease. Then research showed that these healthful fats also may help prevent other serious conditions, such as Alzheimer’s disease, depression, rheumatoid arthritis, macular degeneration and polyps that can lead to colon cancer.

What we’re not being told: A little-known report from the US Dietary Guidelines Advisory Committee has estimated that about 70% of Americans are deficient in omega-3s.

So how do you know whether you’re getting enough of them?

Recent development: A simple test that measures total omega-3s in the blood can tell you whether your levels are adequate. With this information, you don’t have to guess any longer whether you need to eat more omega-3–rich foods or take a dietary supplement.


To gain the wide-ranging health benefits of omega-3s, we have all been encouraged to eat oily fish, such as salmon and sardines, at least twice a week…and/or increase our intake of plant foods, such as flaxseed or walnuts, that contain alpha-linolenic acid, which helps the body manufacture the omega-3 fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). In many cases, people also take fish oil supplements to boost their omega-3 levels.

But even by boosting your intake of omega-3–rich foods and/or taking a supplement, you might not have enough of the fatty acids in your body—everyone absorbs varying amounts of omega-3s and needs different amounts to optimize health.

That is why I recommend an omega-3 blood test for all adults. Not all doctors offer this test, but it’s the best way to determine exactly what levels of omega-3s are in your body. What you need to know about omega-3 testing…

How it is done. The omega-3 index is a simple blood test. Your doctor will take a blood sample, which is analyzed in a laboratory. Home tests are also available in which you do a “blood stick” and mail the sample to a testing laboratory. However, I prefer the test that is performed in a doctor’s office.

What it does. The test measures the two omega-3 fatty acids, EPA and DHA, that are present in the membranes of red blood cells.

Omega-3s are deposited in these membranes whenever you consume food or supplements that contain the fatty acids or alpha-linolenic acid, which is converted into the healthful fats. Red blood cells live for about four months in the body, so the test shows what level of omega-3s you’ve absorbed over that period.

What to look for. The test lists your level of omega-3 fatty acids as a percentage of total fatty acids in cell membranes.

The optimal level of omega-3s (EPA and DHA combined) is 8% or higher—this means that you have the lowest risk of developing heart disease (not including risks from other factors, such as smoking, elevated blood fats, hypertension and diabetes). Below 4% indicates an elevated risk of developing heart disease. A level between 4% and 8% is considered suboptimal.

Typical cost: $100 to $200. The test is not covered by insurance, but this might change in the future as more doctors recognize its clinical value. Labs that offer the test include Health Diagnostic Laboratory, 877-443-5227,…and OmegaQuant, 800-949-0632,


The most important question to ask after any medical test is, “What do I do with the results?” The omega-3 index can be a strong motivator. People already know if they are eating a little or a lot of fish…they also know if they are taking omega-3 supplements.

What people don’t know—without testing—is whether they have enough omega-3s in the bloodstream. When they see that they have a low percentage of omega-3s, they’re more likely to make the necessary changes. My advice…

Get tested annually. First, get an initial baseline test. If a patient’s levels are low, I typically advise that he/she eat more oily fish. Since many people don’t like the taste of fish, it’s fine to take a daily fish oil supplement instead. The test can then be repeated in a year.

Eat much more fish. If you do eat fish, the American Heart Association’s advice to consume it twice a week probably represents the minimum that you need to derive health benefits from omega-3s. More is better, particularly if you already have heart disease (or risk factors for it) and/or your omega-3 levels are low.

My advice: Eat fatty fish at least four times a week (avoid fish that is high in mercury, such as king mackerel). Keep in mind that some people can eat fish every day and still have suboptimal omega-3 levels due to variations in absorption and metabolism. These people will need to also take supplements to raise their omega-3 levels.

Take fish oil supplements. They are an effective way to increase blood levels of omega-3s. Ask your doctor what dosage is most appropriate for you.

Also important: Be sure to check with your doctor if you take a blood thinner. Because fish oil has a blood-thinning effect, there is the possibility of excessive bleeding in people taking warfarin (Coumadin) or another blood thinner.

Reduce side effects. Fish oil supplements are among the safest dietary supplements. Some patients might complain about minor stomach upset or the occasional fishy burp. However, the majority of people taking fish oil have no side effects at all.

Helpful: Divide the dose by taking half in the morning after a meal and the second half later in the day after a meal. This helps prevent an upset stomach and other possible side effects.

“Burp-free” fish oil supplements are another option. They do not cause a fishy aftertaste. Look for products that state “odorless” or “burp free” on the label.