The Benefits of Fatty Fish for Your Heart

David Juan, MD

(Note: This week, Dr. Juan will be focusing on the benefits of omega-3 fatty acids, especially for your heart. Here's part one of his three-part series)

Few bits of food-related health advice have as much power behind them as this one: the more fatty fish you eat, the stronger your heart is. The omega-3 fats within fish are truly some of the most powerful food cures in the world. In part one, we'll look at the overall effects of fish oil, and how it protects against coronary events.

Omega-3 fatty acids from fish include eicosapaentenoic acid (EPA) and docosahexaenoic acid (DHA). In the last 100 years, dietary intake of omega-3 has slowly decreased and the intake of omega-6 has increased. Today, the average North American diet's ratio of omega-6 to omega 3 is 16:1, as compared to a ratio of 1.5:1 about 200 years ago.

Omega-3 fatty acids benefit the cardiovascular system in many ways. For example, they:
-- Improve your cholesterol profile; in particular, triglyceride levels

-- Lower blood pressure

-- Improve endothelial (cells lining blood vessels) function

-- Are anti-inflammatory

-- Reduce plaque formation in the arteries

-- Prevent blockage in the flow of blood by preventing platelets from bunching up

-- Fight irregular heartbeat by reducing abnormal electric impulses arising from the heart

Now, the largest trial to study the preventive effect of fish oil on coronary events was conducted in Japan. In this trial, 18,645 people were recruited, of which 31% were men between 40 to 75 years and the rest were postmenopausal women at least 75 years old with cholesterol levels over or equal to 250 mg/dL.

Coronary artery disease, high blood pressure, and diabetes were the most common diseases found in this group -- at 20%, 36% and 15%, respectively. The subjects received either drug treatment or drug treatment plus fish oil (EPA 1,800 mg/day). It is to be noted that 1,800 mg a day might be fine for Japanese people who are used to eating plenty of fish in their diet, but it's not in the U.S. As well, the most common fish oil supplements used in the U.S. contain only 180 mg of EPA.

The major findings from this large trial included the following:
-- The EPA-treated group had a 19% reduction in major coronary events

-- The EPA group had a significant reduction in unstable angina and non-fatal coronary events

-- There was no difference in sudden deaths in the EPA versus non EPA groups

--There were more mild adverse events in the EPA group, mostly gastrointestinal, skin and abnormal liver function tests.

Source:
The Benefits of Fatty Fish for Your Heart Yokoyama, M., et al., "Effects of eicosapentaenoic acid on major coronary events in hypercholesterolaemic patients (JELIS): a randomized open-label, blinded endpoint analysis,"Lancet, 2007; 369: 1,090-8.

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