Cancer, diabetes, depression, heart disease, stroke, Alzheimer's—these seemingly diverse diseases are increasingly thought to have a common denominator: inflammation. While our genetic predisposition for disease can't be changed, we can do something about this other major player.
Normally, inflammation is part of a healthy immune response, an orchestrated onslaught of cells and chemicals that heal injury and fight infection—think redness, pain, swelling. But the process also has a quiet, dark side. Chronic "hidden" inflammation occurs throughout the body when something kick-starts the immune system and disengages the shut-off button. What ignites the fires differs from person to person: repeated or prolonged infections, smoking, or gum disease, for example. Obesity, too, makes you prone to inflammation, as fat cells churn out inflammatory proteins called cytokines. But the end result is the same: An endless trickle of immune cells interferes with the body's healthy tissues, triggering genetic mutations that can lead to cancer or the bursting of plaque in an artery wall.
Scarier still, most people don't even know they're inflamed. There's not a reliable blood test yet to screen for inflammation. A test that measures an inflammatory marker called C-reactive protein is currently recommended for those at increased risk of heart disease, because high levels of CRP, for these folks, are associated with future heart attacks and strokes. But it's not used as a general screen because researchers still don't know what role CRP plays and whether it's truly a sign of increased risk of disease. What is clearly established, however, is that people with poor health habits tend to have higher levels of inflammation. And the latest science suggests that we can take action.
"In recent years, we've come to accept that inflammation plays a role in many chronic diseases, but it's about an imbalance—too many pro-inflammatory chemicals and not enough anti-inflammatory ones," explains Moise Desvarieux, an inflammation researcher at Columbia University's Mailman School of Public Health. Normally, hours after igniting the fires, the body shoots out anti-inflammatory substances to restore equilibrium.
Thus, staying well means having both systems in working order. Some promising indications that gaining a balance could be protective: According to a Harvard study published last year, cholesterol-lowering statin drugs reduced the risk of heart attacks and strokes in people whose blood analysis indicated excess inflammation, even though they didn't have high cholesterol. That's because statins probably have anti-inflammatory properties. And an August study published in the Journal of the American Medical Association found that colon cancer patients who took a daily dose of anti-inflammatory aspirin reduced their risk of dying from the disease by nearly a third. But experts say medications aren't the antidote to hidden inflammation. Aspirin, for example, can cause stomach ulcers and gastrointestinal bleeding; statins can cause severe muscle aches, and the risks of taking them for decades aren't known. Science suggests, though, that there are safer things you can do to keep from stoking the flames.
- Assess yourself and take action. While being overweight raises your risk of inflammation, your body fat distribution may be even more important. "It's where your body puts the fat, on your waist as opposed to your hips and thighs, that indicates a pro-inflammatory state," says Carol Shively, a professor of pathology at Wake Forest University School of Medicine who has studied body fat distribution. Fat cells that accumulate near organs in your abdominal cavity tend to behave like little factories, responding to stress hormones that you produce when you're frazzled or overtired by pumping out chemicals of their own. The stress hormone cortisol "appears to bind to receptors on these fat cells, setting off a process that promotes the storage of fat and increases the number of fat cells," says Shively. "These extra cells then produce more chemicals that increase inflammation."
Having a large waist measurement—at or above 35 inches for a woman and 40 inches for a man—means you're likely to have excess inflammation. Other red flags: having high blood pressure (a measurement at or above 130/85 millimeters of mercury), high levels of glucose (at or above 100 milligrams per deciliter after fasting), and high triglycerides (150 mg/dL or above, measured by a cholesterol blood test). According to the American Heart Association, these all point to an inflammatory condition called metabolic syndrome, a common precursor of diabetes and heart disease. The best way to reduce belly fat? Eat less and move more.
- Go Mediterranean. Consuming a Mediterranean-style diet—rich in fruits, vegetables, legumes, nuts, olive oil, and fish—is known to protect the heart, and that's probably because it lowers the level of pro-inflammatory chemicals in the body. The diet may also protect against depression by increasing levels of omega-3 fatty acids and antioxidants used by the body to manufacture anti-inflammatory chemicals that increase blood flow to the brain. A study released in October that followed 10,000 Spaniards for more than four years found that those who reported eating a Mediterranean diet had a 30 percent lower risk of developing depression than those who didn't. "This diet fills the bill perfectly, because it contains few of the fats that drive inflammation, like saturated fat in red meat and trans fats in margarine and processed foods," explains nutritionist and family physician Ann Kulze, author of Dr. Ann's 10-Step Diet, "while at the same time being rich in nuts, berries, and dark vegetables that have anti-inflammatory effects."
- Get active, but don't overdo it. There's no question that physically fit folks produce less inflammation than couch potatoes, since regular exercise protects against metabolic syndrome. But research also suggests that superlong workouts can cause inflammation levels to spike for a day or two afterward. David Nieman, a professor of health and exercise science at Appalachian State University in Boone, N.C., conducted studies that found sky-high blood levels of inflammatory chemicals in ultramarathon runners who had just completed 100-mile races. The key is to get enough exercise but not too much. "Being active for 60 minutes at a time will give you all the health benefits you need without raising your levels of inflammation," says Nieman. For those who go beyond that, he recommends taking a fish-oil supplement and a sports drink that contains quercetin (a plant chemical found in apple peels and berries) and green tea extract, like FRS Plus. His new research indicates that those three ingredients together lower levels of inflammation in high-endurance athletes.
- Reduce stress and get adequate sleep. Shively's research has demonstrated that monkeys that were the most subordinate in their social groups—which means they got less grooming from their peers and were often the target of aggression—also put on more belly fat when fed a Western-style diet high in fat and cholesterol compared with monkeys that were at the top of the pecking order. Anything that stresses the body, from too little sleep to too much tension, can cause belly fat to accumulate, she says. Aim for seven to eight hours of sleep per night and simple stress reducers. Shively recommends cutting back on multitasking, which she says "can be very anxiety-provoking."
- Floss and brush twice every day. The link between gum disease and heart disease has been well established, and researchers now think they've pinpointed the possible culprit: The very same bacteria that cause inflammation and swelling in the gums appear to be a source of inflammation and thickening of the arteries. Previous studies have shown that those who get their gum disease treated wind up with lower levels of inflammation, though it's still too early, Desvarieux says, to firmly conclude that gum disease causes clogged arteries. "Still," he adds, "it's hard to be against good oral hygiene."
- Consider probiotics. UCLA School of Medicine researchers made headlines last summer when they reported that intestinal inflammation in mice could cause DNA damage in white blood cells elsewhere in the body, raising the likelihood of cancer. "We demonstrated a whole-body response to site-specific inflammation, which means it's important to prevent that inflammation," says study coauthor Robert Schiestl. He says the beneficial bacteria found in yogurt and probiotic supplements can help keep in check the "bad" bacteria that reside in your gut and generate an inflammatory response. Try a daily serving or two of yogurt and other dairy products containing probiotics—look for L. casei, L. acidophilus, L. plantarum, B. bifidum. You can also try the supplement Align; studies suggest its B. infantis bacteria are anti-inflammatory and help normalize digestive function. And if you're not a dairy fan, a pill may be preferable.