Photo by Hunter Freeman
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Shield Your Heart
By Sid Kirchheimer, January & February 2006
Your immune system can go into overdrive and damage your ticker. Here’s what you can do
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Slash your skin or catch a cold and you'll be thankful for inflammation, a physical reaction that is one of the body's key germ-fighting maneuvers. The obvious signs of inflammation—redness, swelling, and warmth—are evidence that your immune system is working: waging war against marauding microbes and trying to protect surrounding tissue from possible infection.
Usually, once the threat subsides, so does inflammation, and you begin to heal. But inflammatory conditions such as rheumatoid arthritis and asthma; long-term infections; persistent insults such as smoking, obesity, and high blood pressure; or even a genetic predisposition can trigger a state of chronic inflammation. When the immune system doesn't get to shut down, it does damage to the body—including your cardiovascular system.
Growing evidence shows that atherosclerosis, or hardening of the arteries, results at least in part from chronic low-grade inflammation, says Robert O. Bonow, M.D., chief of cardiology at Northwestern University's Feinberg School of Medicine in Chicago and former president of the American Heart Association. First, a state of continuous inflammation may contribute to the development of plaques on the artery walls. But more important, there's very strong evidence that when patients already have some plaque buildup—as we all do by age 50—the immune system perceives this as an injury, sparking more inflammation. "White blood cells that are involved in the inflammatory response attack the plaque," says Bonow. "In doing so, the plaque can rupture, initiating a blood clot."
That may explain why half of all heart attacks and strokes occur in people with normal or even low cholesterol levels, says Paul Ridker, M.D., M.P.H., director of the Center for Cardiovascular Disease Prevention at Harvard's Brigham and Women's Hospital. One in four of these events—which afflict some 2 million Americans a year—strikes people who don't smoke or have high blood pressure, diabetes, or high cholesterol. "Our research finds that people with high inflammation levels but low cholesterol have a worse survival rate than people with high cholesterol and low inflammation," says Ridker, who is widely considered a pioneer in researching the inflammation-cardiovascular disease link.
A simple blood test can determine your inflammation level by measuring the C-reactive protein (CRP), a molecule produced by the liver in response to an inflammatory signal (see "Testing for Trouble" below). A CRP reading above 3.0 milligrams per liter means a tripled risk of heart attack, even when cholesterol levels are normal. Here's how to lower your CRP level.
1. Brush and floss
Research now links gum disease and tooth loss with a higher risk of atherosclerosis and higher CRP levels; one study even suggests that cavities, gingivitis, and missing teeth are stronger predictors of cardiovascular problems than high cholesterol or triglycerides. Bacteria that cause these ailments in the mouth can appear in the same atherosclerotic plaque associated with cardiovascular disease, explains Michael P. Rethman, D.D.S., past president of the American Academy of Periodontology.
Though doctors don't know how or even whether the bacteria travel from one site to the other, one theory is that mouth bacteria enter the bloodstream directly through the inflamed gum tissues. The best defense is dental hygiene: brush at least twice a day with a soft-bristle brush, and floss daily.
2. Butt out
"When you smoke a cigarette, over a thousand chemicals enter your body, many of them irritants that get into the bloodstream, triggering an inflammatory response," says William Joel Meggs, M.D., Ph.D., author of The Inflammation Cure (McGraw-Hill, 2004).
Smoking is especially inflammatory to an artery's endothelium, its interior lining. Because each cigarette adds new damage, the blood vessels never have time to heal, making them magnets for fatty plaque. Quitting the habit immediately reduces inflammation and eventually reduces the risk of cardiovascular disease back to levels for nonsmokers.
3. Banish the belly
Any excess poundage is a possible inflammation inducer, because fat cells are a virtual factory for producing inflammatory molecules. But belly fat is particularly dangerous. "Fat tissue inside the abdominal cavity is especially metabolically active—secreting even more harmful proteins into the bloodstream," says Bonow. And recent research finds that women ages 50 to 70 whose waists are larger than 35 inches also had lower levels of a specific inflammation-fighting hormone.
To lose one pound per week, forgo or burn 500 calories per day. And to battle that killer belly fat, you'll need regular aerobic exercise. You can burn 500 calories and get your aerobic workout done by walking five miles a day.
4. Rethink your diet
You already know fatty, cholesterol-laden foods can clog your arteries. And scientists are coming to believe that white bread, baked potatoes, and other foods with a high glycemic index—that is, the foods that are digested and converted to glucose most quickly—can harm them, too, contributing to inflammation by causing quick, dramatic spikes in blood sugar, increasing the production of free radicals that damage cells and trigger inflammation.
But if some foods hurt your arteries, other foods can help protect them. Leading the pack of good guys are foods rich in inflammation-fighting omega-3 fatty acids—olive oil, walnuts, and cold-water fish such as salmon, mackerel, and herring. One study showed that 1,000 milligrams of fish-oil capsules per day can lower the risk of sudden cardiac death by nearly half.
And there's growing evidence that plant foods rich in certain disease-fighting natural chemicals may also have a potent anti-inflammatory effect. Meggs's top choices: tomatoes, blueberries, eggplant, and fiber-rich grains.
For optimal heart health, choose whole grains over processed white flour, and eat at least five servings of fruits and vegetables daily. Also, eating smaller, more frequent meals causes a slower spike in blood glucose—and therefore less inflammation—than having one or two larger meals a day.
5. Stay in for lunch
Long-term exposure to air pollution—specifically from car exhaust and coal-fired power plants—poses a greater risk of death from heart disease than from respiratory ailments.
"It appears that air pollution provokes inflammation and accelerates atherosclerosis," says C. Arden Pope III, Ph.D., an epidemiologist at Brigham Young University in Provo, Utah, who authored a large study on the subject. When all heart-hurting health risks were factored in, he found, people living in the most-polluted cities—including Los Angeles, Houston, New York, and Atlanta—faced a 25 percent to 30 percent higher risk of heart disease than those in the communities with the cleanest air. "That's similar to the risk of living with a smoker," he says.
Since air and ozone pollution tend to peak between noon and 4:00 p.m., try to limit outdoor activities then. "And whenever you exercise, the farther you are from busy streets with a lot of traffic, the better," Pope adds.
6. Don't have a cow
Anxious or depressed people have higher rates of heart disease, and some studies find they have higher rates of inflammation. Whether stress causes inflammation is still under investigation, but it's well established that cortisol, adrenaline, and other stress-related substances damage the endothelium, possibly contributing to the development of atherosclerosis.
Meditation and other stress-management strategies not only put the brakes on this effect but, in combination with a heart-healthy diet, may reverse it, says Richard C. Becker, M.D., director of Duke University's Cardiovascular Thrombosis Center. Other proven methods include exercise, regular robust laughter, and having pets. Exercise and laughter also relax blood vessels and improve blood flow.
7. Raise a glass
Red wine grabs the headlines for its antioxidant-fueled, heart-helping abilities, but studies show that any alcohol—in moderate doses—has an anti-inflammatory effect. "One beer, one whiskey, or one glass of wine all seem to have the same effect," says Ridker. "But one drink a day doesn't mean having seven only on Saturday night." Too much alcohol is much worse for you than drinking none at all.
Scientists are still sorting out the connection between inflammation and heart disease, as well as inflammation's possible link to Alzheimer's disease and various forms of cancer. But in the meantime, keeping inflammation to a minimum makes good sense.
Sid Kirchheimer last wrote for AARP The Magazine about how to boost age-related senses loss ("Sensational Tune-Ups," September & October 2005).
Testing for Trouble
The best way to determine your body's inflammation level is with a simple blood test to measure the C-reactive protein (CRP). But make sure to get the right test.
A general CRP test measures inflammation throughout the body. The so-called high-sensitivity CRP (hs-CRP) test, on the other hand, is more specific to gauging inflammation in blood vessels. Your doctor can order this test as an add-on to your cholesterol screening. If your insurance doesn't cover it, the analysis could add about $25 to $50 to the cost of a blood test.
The American Heart Association (AHA) recommends only limited use of hs-CRP testing, for those at increased risk of cardiovascular disease, including smokers and people with diabetes. According to the AHA, an hs-CRP reading above 3.0 milligrams per liter (mg/L) puts you in the danger zone. Between 1.0 mg/L and 3.0 mg/L indicates an average risk; below 1.0 mg/L, a low risk.
But hs-CRP testing should be done only when you're not injured or sick: trauma or an infection can spike CRP levels to 1,000 mg/L or higher.
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