Reversing Heart Disease Through Diet

Most people with coronary heart disease have a checkered history with food. They've eaten a few too many pizzas and french fries, perhaps, and not quite enough fruits and vegetables. Maybe you can relate. But if your heart's in trouble, this is no time to regret your past indulgences. Instead, it's time to turn food into an ally. A healthy diet can go a long way toward preventing a heart attack. and it might even help clear your arteries.

The healthy diet basics

Diets are as individual as people. The foods you choose depend on your personal tastes and goals. But there's one rule that applies to everyone with coronary heart disease: You have to go easy on fats, especially saturated fats. Your body quickly turns saturated fat into LDL cholesterol, the "bad" cholesterol that clogs your arteries.

According to the American Heart Association (AHA), people with coronary heart disease should get less than 30 percent of their calories from fat and less than 7 percent from saturated fat. For a standard 2,000-calorie diet, that translates to less than 67 grams of fat and 16 grams of saturated fat. This guideline alone may go a long way toward lowering your cholesterol and cutting your risk of a heart attack. Reading package labels on processed foods will tell you how many grams of saturated fat you'll get in one serving; animal products (including milk, cheese, and meat) are also high in saturated fat, as are scones, cookies, pizza, and other baked food rich in butter, cheese, or cream.

Saturated fat is often cast as the ultimate villain, but another type of fat can be even more dangerous to your heart. Trans unsaturated fats or trans fats -- sometimes found in stick margarine, fried fast foods, and some cookies or other snack foods -- increase LDL levels and lower your HDL, the "good" cholesterol that helps keep your arteries clear. A Harvard University study of more than 30,000 women found that those with the highest levels of trans fats in their blood had three times the risk of heart disease that of those with the lowest levels of trans fats. According to the Harvard School of Public Health, for every extra 2 percent of trans fat calories per day, the risk of heart disease goes up by 23 percent. (Watch for "partially hydrogenated vegetable oil" on the product label -- that's code for "trans fat." Since January 2006, food manufacturers have been required to list trans fats on the nutrition content labels of all their products as well.)

"Healthier fats" may sound like a contradiction, but some types of fat really can help protect your heart. At the top of the list are monounsaturated fats found in olive oil, canola oil, and some nuts. These fats actually reduce your LDL cholesterol level and slow the progression of heart disease. Polyunsaturated fats -- found in corn oil, soybean oil, and many margarines -- also reduce LDL cholesterol, but they may worsen coronary heart disease by making the remaining cholesterol "stickier." Omega-3 fatty acids -- found in fatty fish such as salmon and some fish oil or flaxseed supplements -- may also lower your cholesterol and actually benefit your heart.

Changes in diet can have pretty immediate results. French researchers saw a 15 percent reduction in cardiovascular disease risk factors among 212 participants who followed the healthier-fats Mediterranean diet for a 3 month period. Bad cholesterol levels fell significantly, according to the study in the November 2005 issue of the American journal of Clinical Nutrition.

Of course, fats aren't the only part of your diet worth watching. If you already have heart problems, the AHA recommends getting less than 200 milligrams of cholesterol each day. Since one egg contains 213 mgs of cholesterol, you'll need to watch your egg consumption closely. Try to get at least 55 percent of your calories from carbohydrates, especially complex carbohydrates. That translates to five to nine portions of fruits and vegetables and generous amounts of whole grains every day.

Putting more fruits and vegetables into your diet shouldn't be hard work. Most people can cut their consumption of saturated fat and trans fats in half by avoiding butter, margarine, fatty meats, and dairy products made from 2 percent or whole milk.

The Ornish and Mediterranean diets

The AHA diet is practical and effective. But does it go far enough? A few studies have suggested that patients with heart disease may do even better on more highly specialized diets. A study published in the journal of the American Medical Association in 2003 suggests that a vegetarian diet low in saturated fat could be as effective in lowering cholesterol as statin drugs. The University of Toronto study concluded that patients with high cholesterol would benefit greatly from consuming lots of plant fiber and little fat.

Two diets in particular have grabbed most of the headlines: the Mediterranean diet and the Ornish diet, a regimen developed by Dr. Dean Ornish. The first is just a slightly modified version of the AHA diet; the second takes a radical approach to the concept of "low fat." Each diet has its advantages, and each can help guide your own healthy choices.

Like the AHA diet, the Mediterranean diet provides up to 30 percent of calories from fat. However, most of those fats are heart-healthy monounsaturated fats from olive oil or canola-based margarines. The diet is also rich in legumes, foods such as peas and beans that lower LDL cholesterol while sparing the good HDL cholesterol.

The formula seems to work. A study of more than 400 heart attack survivors, published in the journal Circulation, suggests that the Mediterranean diet may be a potent weapon against heart disease. Compared with patients on a standard low-fat diet, patients on the Mediterranean diet were about 70 percent less likely to have another heart attack or die of heart trouble over a span of five years. They were also about 70 percent less likely to suffer from chest pains (angina), stroke, heart failure, or blood clots in the lungs.

The Ornish diet takes the concept of "low-fat" to extremes. In this diet, the ratio for fat intake drops from less than 30 percent of all calories to less than 10 percent. Patients shun meat and all other animal products except egg whites and fat-free dairy items, and they avoid other fatty foods such as avocados, nuts, and seeds. (Some of his patients chose to take 3 to 4 grams of uncooked flax seed oil daily, which is rich in omega-3 fatty acids.) In addition to going low-fat, they get a scant 5 mg of cholesterol each day. To fill the void of fatty foods, they eat plenty of fruits, vegetables, and grains -- enough to have carbohydrates make up 75 percent of the daily calories. The Ornish program also calls for regular exercise and one hour each day of a stress management technique such as yoga or meditation.

For patients who can stick to it, the Ornish approach can offer great rewards. In a landmark study of 35 patients with coronary heart disease published in the December 16, 1998 issue of the journal of the American Medical Association, Ornish and his colleagues reported that the diet actually helped reverse the disease. After five years of the Ornish program, patients' arteries opened by an average of almost 10 percent. Among patients who followed a regular recovery plan, cholesterol buildup in the arteries got about 30 percent worse in those five years. Perhaps not surprisingly, the patients who didn't participate in the Ornish program were more than twice as likely to suffer a heart attack, enter a hospital for heart problems, or die of heart trouble. A review of popular diets in 2007 also found that the Ornish diet had an increased capacity for cardiovascular disease prevention.

Low-Carb Diets

Surprising many, several recent studies have found that a high-protein/low-carbohydrate diet (even one high in saturated fat like the Atkins diet) may have beneficial effects on cholesterol levels as well. For example, a study published in the journal of the American Medical Association (JAMA) in March 2007 found that overweight women lost more weight after a year on the Atkins diet than women on the Zone diet or low-fat diets. Also, at the end of the year, those on the Atkins diet showed comparable or better progress in their cholesterol levels than those in the other diet groups. A two-year study published in 2008 studied low-carb, low-fat and Mediterranean diets and found that low-carb and Mediterranean diets are both effective for weight loss and just as safe as a low-fat diet. Another study published in JAMA in May 2007 found that a low-carb diet improved HDL (good) cholesterol and triglyceride levels more than a low-fat diet, but the low-fat diet was better at reducing LDL (bad) cholesterol. None of these studies lasted more than two years, however, and there is conflicting evidence as to the long-term effect of low-carbohydrate diets on cholesterol levels and heart health.

The real world

Results from these diets have raised many questions, most of them still unanswered. To begin with, which parts of the diets are really protecting the heart? In the case of the Ornish program, could the exercise and stress management be even more beneficial than the fat reduction? Perhaps more important, how many people with coronary heart disease could ever hope to stick to any of these regimens?

If you can't imagine giving up meat or devoting yourself to beans and olive oil, don't despair. For any patient with coronary heart disease, the AHA diet -- less than 30 percent of calories from fat, less than 7 percent from saturated fat -- is an excellent place to start. From there, you can always decide to cut fat a bit further or use olive oil instead of butter. You may end up with a diet of your very own -- something you can really live with.

-- Chris Woolston, M.S., is a health and medical writer with a master's degree in biology. He is a contributing editor at Consumer Health Interactive, and was the staff writer at Hippocrates, a magazine for physicians. He has also covered science issues for Time Inc. Health, WebMD, and the Chronicle of Higher Education. His reporting on occupational health earned him an award from the northern Califo
ia Society of Professional journalists.