Broad-spectrum Cardiac Protection with Fish OilSeptember 2006
In this article, I will share with you the extraordinary success story of Stacy—a patient who came to me with a cholesterol level at a whopping 594 mg/dL and triglycerides that were off the chart at 2,893 mg/dL—and her amazing turnaround in blood test results achieved through the use of fish oil.
A Patient at Risk: Stacy’s Frightening Blood Test Results
Stacy, a 40-year-old physical therapist, was terrified to learn the results of her most recent cholesterol tests: dangerously elevated total cholesterol of 594 mg/dL and sky-high triglycerides of 2,893 mg/dL. Because these values were so high, her levels of dangerous low-density lipoprotein (LDL) and beneficial high-density lipoprotein (HDL) could not be determined.
When I met with Stacy, she was in a panic. In tears, she declared, “I don’t understand it. I take good care of myself. I don’t eat fatty foods, I exercise, I don’t do anything wrong!”
She was correct. Her frightening lipid levels were not due to anything “bad” she had done, but instead were a combination of genetics (“familial hypertriglyceridemia”) and modest dietary excesses. However, these levels of triglycerides and cholesterol posed risks for liver disease and pancreatic disease (pancreatitis), as well as heightened long-term risk for heart disease and stroke. Stacy also showed some features of the metabolic syndrome: her blood sugar was slightly elevated at 114 mg/dL, her blood pressure was high at 140/88 mmHg, and she showed an excess of abdominal fat, standing 5 feet, 5 inches tall and weighing 160 pounds.
Fish Oil Lowers Triglycerides
Dangerously high levels of triglycerides have become more common as Americans develop metabolic syndrome. Elevated triglycerides greatly increase risk for heart disease. Omega-3s can significantly reduce triglyceride levels and help correct other cardiac risk factors that accompany metabolic syndrome.1-3 In fact, omega-3 fatty acids derived from fish oils are now available in the form of a prescription drug called Omacor®, which has been approved specifically for the treatment of elevated triglycerides.4 (For more on this subject, see this month’s “As We See It.”)
Fish Oils Rich in Omega-3s Fight After-Meal Surges in Blood Fats
An exciting area of research focuses on post-meal elevated blood fat (lipid) levels, known as post-prandial hyperlipidemia. This is essentially the flood of fat in the blood that occurs following a meal, which scientists suspect may be a potent contributor to atherosclerosis (and acute heart attack).5 A unique effect of omega-3 fatty acids (found in cold-water fish oil) is to accelerate the clearance of fat-containing particles from the blood following meals. Fish oil’s profound fat-clearing ability has important implications for cardiovascular disease prevention.6
Omega-3s Slow Plaque Growth and Prevent Blood Clots
Heart attacks can result from unstable atherosclerotic plaque. The rupturing of unstable plaque inside a coronary artery has been compared to a kernel of popcorn bursting open and occluding (blocking) the flow of blood through the vessel. These kinds of heart attacks can occur suddenly, without typical symptoms such as angina and shortness of breath. Omega-3s from fish oil may help to modify the structure of atherosclerotic plaque in ways that make it less dangerous. In fact, studies show that omega-3s can slow the rate of atherosclerotic plaque growth.7,8
A fascinating study showed that omega-3 supplementation actually changed the composition of unstable atherosclerotic plaque, making it less likely to rupture and thus less dangerous. Subjects who had severe carotid plaque and were scheduled to have it surgically removed received either fish oil or sunflower oil prior to surgery. When the plaque was removed at surgery and examined, researchers found that those who took fish oil had less plaque inflammation as well as more stable plaque. By contrast, those who took sunflower oil had more unstable, rupture-prone plaque.9
The omega-3 fatty acids found in fish oil also help reduce certain proteins that promote abnormal blood clotting and inhibit platelet aggregation, two effects that reduce the likelihood of clot formation on active, ruptured coronary plaque that could result in a heart attack.19
Although the blood-thinning effect of fish oil is modest, people who suffer from an abnormal bleeding tendency or use blood-thinning drugs such as Coumadin® should consult a physician before taking fish oil. The best way of determining if one is taking the optimal dose of Coumadin® and fish oil is to have a doctor perform a template bleeding time test. (Details about this test can be found in the Thrombosis Prevention chapter of the Disease Prevention and Treatment book. )
Omega-3s Normalize Heart Rhythm, Prevent Sudden Cardiac Death
One of the most dramatic benefits of fish oil is its ability to prevent sudden death, particularly sudden cardiac death. Scientists believe that omega-3 fatty acids from cold-water fish may help prevent these sudden deaths by reducing potentially fatal abnormal heart rhythms, or arrhythmias.
To investigate the life-saving benefits of fish oil, scientists studied more than 2,000 men who had previously suffered a heart attack. Some of the men were advised to regularly consume cold-water fish, while others did not receive this dietary advice. After two years, the difference in mortality between the two groups was dramatic: men who ate fish twice a week had a 29% lower rate of death than those who did not. Scientists believe that fish oil helped prevent death by suppressing dangerous, abnormal heart rhythms in these men with a history of heart muscle damage.20
Another important study showed that people dying from sudden cardiac death had lower blood levels of omega-3 fatty acids than those who did not. Eating one or more servings of fish each week produced important heart-protective benefits, reducing the risk of sudden cardiac death by a stunning 52%.21
A major clinical study provides more good news about fish oil. In this large study of more than 11,000 adults, those who consumed 1000 mg of EPA and DHA daily had a 30% reduced rate of cardiovascular death and a 20% lower rate of sudden death. Moreover, the protective benefits of fish oil were apparent after only a few months of supplementation.22
Fish oil’s ability to promote healthy heart rhythms is so impressive that some cardiologists now recommend it for their patients who have the implanted devices known as defibrillators to prevent life-threatening heart arrythmias.23,24 In this patient population, the goal of supplementation with omega-3 fatty acids is to reduce rhythm instability.
Fish oil is particularly effective in fighting the common but worrisome heart arrhythmia known as atrial fibrillation. This is especially important, as atrial fibrillation increases the risk of stroke. One study showed that fish oil effectively reduced the incidence of atrial fibrillation by a remarkable 54% in people recovering from bypass surgery.25
Scientists have observed that people who suffer heart arrhythmias often demonstrate low levels of omega-3 fatty acids in their blood, further suggesting that omega-3 supplementation is clinically useful for promoting healthy heart rhythm.24