During the last several years, researchers have been quietly piling up evidence to support a truly groundbreaking idea — that there may be one common link between many seemingly unrelated health conditions. That link is inflammation, an immune-system response that causes a stubbed toe to swell and an infection to bring on a fever. In fact, it's become the medical buzzword of the moment, and for good reason. Studies have shown that people with chronic inflammation are at a high risk for certain health problems, including heart disease and cancer, says Lisa M. Davis, PhD, a research associate at the Johns Hopkins School of Public Health's Center for Human Nutrition. Many researchers believe that ongoing inflammation — caused by a variety of factors — is one of the reasons that seemingly healthy people develop heart disease and diabetes, and experts estimate that it may be behind 15 percent of all cancers. Inflammation may also be linked to autoimmune diseases — prevalent in women — such as rheumatoid arthritis, lupus, and thyroid deficiency.
Fortunately, there's a lot you can do with exercise and diet to ward off inflammation. Here's what you need to know.
Your body creates inflammation as a quick way to heal everything from paper cuts to the flu. Essentially, the immune system increases blood circulation to the injured area, instigates infection-fighting heat, and sends white blood cells and other chemicals to ward off bacteria and mend damaged cells. When it's doing that job, inflammation is a good thing. The long-term harm happens when the body continuously produces low-grade inflammation; unfortunately, the odds are high that you don't even know the damage is being done. Even doctors can't always point to where chronic inflammation is located in the body, and what its specific causes are.
In general, though, inflammation may be triggered by conditions such as chronic back pain, ongoing infections like tuberculosis, viruses, bacteria, allergies, and even gum disease. Excess weight is also considered a major inflammation engine, because extra pounds don't just get stored in the body as lethargic blobs of flab. Body fat, especially in the gut, is active tissue. It produces hormones and secretes substances just like an organ, and some of these can trigger inflammation, says Barbara Nicklas, PhD, a professor of medicine at Wake Forest University Health Sciences in Winston-Salem, North Carolina. In one study, dropping even a few pounds caused inflammation to nose-dive. (A blood test can reveal your body's current inflammation levels — see "Are You at Risk?")
Even before it gets stored in your midsection, however, dietary fat in the foods you eat can affect inflammation. Certain types of fat promote this reaction, while others fight it. Although this relationship is just beginning to be understood, read on to identify the major culprits.
The Major Culprits
Saturated fat is found mostly in animal-based foods like red meat and whole-fat dairy products. "It's bad both for the old-fashioned reason that it raises LDL [bad] cholesterol and also because it promotes inflammation throughout the body," says Linda Antinoro, RD, a dietitian at the Nutrition Consultation Service at Brigham and Women's Hospital in Boston, where much of the research on inflammation has been done.
Trans fats — chemically altered fats often found in crackers, cookies, and other baked goods — send bad cholesterol soaring and promote inflammation even more than saturated fat does. That's why doctors recommend cutting trans fats out of your diet completely. They've been clearly marked on nutrition labels since a new law requiring this went into effect at the start of the year.
Omega-6 polyunsaturated fat may also have inflammatory components and is probably not even on your radar. That's because food labels don't list omega-6 specifically; it's included under the umbrella of all polyunsaturated fats. Omega-6 is found in corn, soybean, sunflower, and safflower oils; it's also in packaged goods that list these oils as ingredients — and the grocery-store shelves are full of them.
Until very recently, omega-6 has been viewed as healthier than saturated and trans fats, because it may improve cholesterol levels. However, research now suggests that in the fight against heart disease, and possibly other ailments, lowering cholesterol may not be as beneficial as lowering inflammation. And that's where omega-6's dark side comes into play: It appears to boost inflammation. In one study, people who consumed more omega-6 fat had higher blood-sugar levels and less insulin sensitivity — two risk factors for diabetes.
The body needs a certain amount of omega-6 each day to function properly — about that found in a tablespoon of Thousand Island dressing or a 1-ounce bag of reduced-fat potato chips. But because it's so prevalent in packaged foods, the typical American consumes far more than this, says Davis — and to the exclusion of inflammation-fighting fats.
Sugar and other simple carbs can make your blood sugar spike; this has been linked with higher levels of inflammation. A high sugar intake may not trigger inflammation on its own, says Davis, but it may worsen the effects of unhealthy fats.
As we learn more about inflammation, we'll have a better understanding of how to manage it. But there are three simple ways you can start fighting it today.
- Shed excess pounds. Losing just 5 percent of your body weight can lower your risk of cardiovascular disease and diabetes, mainly because you're losing the visceral abdominal fat that pumps out the most inflammatory triggers, says Davis.
- Get moving. Exercise by itself is linked to lower levels of inflammation, probably because it tends to burn inflammatory flab from your gut first, Davis says. A study published in the journal Circulation in 2002 showed a correlation between higher fitness capacities in women and lower inflammation levels.
- Adjust your diet. Certain foods can directly affect whether your inflammation dial is set to simmer or is turned off.
Here are some of the most effective anti-inflammatory foods:
Fish, Canola Oil, Walnuts. These foods are high in omega-3, another type of polyunsaturated fat, which, unlike omega-6, can help counteract inflammation. In fact, in a 2004 study in the Journal of the American Medical Association, people placed on a Mediterranean diet that included foods high in omega-3 had less inflammation, lost more weight, metabolized insulin better, and had healthier blood vessels than people who ate just as healthfully but weren't on this diet. Most Americans don't get nearly enough omega-3 in their diets. Aim for more than two grams of omega-3 a day, from both plant and fish sources. A three-ounce serving of salmon has 1.2 grams and one ounce of walnuts contains 2.6 grams.
Olive Oil, Peanut Oil, Nuts, Avocados. These foods are rich in monounsaturated fat. Monos on the whole appear to be anti-inflammatory and are already associated with improving the body's cholesterol balance. But olive oil may have some unique anti-inflammatory powers as well, according to research at the Monell Chemical Senses Center in Philadelphia. Taste experts there noticed that extra-virgin olive oil produces a "bite" in the throat similar to that of ibuprofen, a nonsteroidal anti-inflammatory drug. In tests, they discovered a compound in olive oil called oleocanthal that may fight inflammation in a way similar to that of NSAIDs.
Fruits, Vegetables, Whole Grains. These foods provide a different inflammation defense: antioxidants, which may affect inflammation in the same way that closing the damper affects a fire. Antioxidants include vitamins A, C, and E, as well as phytonutrients like carotenoids (found in orange and yellow vegetables such as carrots and sweet potatoes) and flavonoids (found in red and purple fruits such as apples, berries, and grapes). Look for produce with deeper or brighter colors, which tend to contain the most antioxidants. According to government recommendations, you should eat two cups of fruit and two and a half cups of vegetables every day, choosing from a variety of colors throughout the week.
Herbs, Spices, Teas. Cinnamon, curry, dill, oregano, ginger, and rosemary are all concentrated sources of antioxidants that can fight inflammation. Most teas are also chock-full of them, including the green, black, white, and oolong varieties.
Are You at Risk?
Do You Have Chronic Inflammation?
One way to tell is to get a high-sensitivity c-reactive protein test (hs-CRP). CRP is a compound in the body that becomes elevated during inflammation, and this test can give you some idea of your future heart disease risk, according to Harvard research. Not everyone needs to be screened, but you may want to ask your doctor about getting tested if you have a family history of heart disease — especially if you already have risk factors such as high cholesterol (over 200) or high blood pressure (greater than 140/90). Some other health conditions may raise your risk of inflammation, so also consider a CRP test if you have insulin resistance, diabetes or an autoimmune disease, says Lisa M. Davis, PhD.
Sample Meal Plan
The Anti-Inflammatory Diet
How can you incorporate foods that fight inflammation into your daily eating plan? Linda Antinoro, RD, and Julie Redfern, RD, dietitians at Brigham and Women's Hospital in Boston, offer the following healthier alternatives to the typical American diet:
Typical Choice: Large bagel with cream cheese and a 20-ounce coffee with cream and sugar
Better Choice: A cup of oatmeal with skim milk, two tablespoons of raisins, and one tablespoon of walnuts; a half cup of blueberries; a cup of green tea
Why: Oatmeal contains flavonoids and has no saturated fat, unlike the cream cheese and light coffee's 13 grams. Raisins are among the most powerful antioxidant foods, according to an analysis by the U.S. Department of Agriculture Agricultural Research Service; blueberries come in second. Walnuts are high in omega-3 fatty acids; green tea is rich in antioxidant polyphenols but isn't linked to increased inflammation the way moderate-to-heavy coffee drinking is.
Typical Choice: Cheeseburger with fries and a 20-ounce soda
Better Choice: Turkey sandwich with 3 ounces of meat, 100 percent whole wheat bread, red leaf lettuce, tomato, and 1 teaspoon mayonnaise; 6 ounces of 100 percent fruit juice.
Why: The sandwich has 10 to 15 fewer grams of saturated fat than a cheeseburger and fries, while the tomato, lettuce, and whole-grain bread contain antioxidants lycopene, anthocyanins, and lignans, respectively. Fruit juice provides antioxidants as well, unlike sugary soft drinks, which some research links with markers of inflammation in women. And the small amount of omega-6 in mayo's soybean oil is okay if the rest of your diet is healthy.
Typical Choice: Three chocolate chip cookies
Better Choice: Two tablespoons mixed nuts and 3/4 cup grapes
Why: Nuts are rich in monounsaturated fat; grapes contain anthocyanins.
Typical Choice: Six-ounce steak, packaged white-rice side dish with powdered cheese and seasonings, and green-bean casserole
Better Choice: Three ounces of baked wild salmon sprinkled with oregano; 1/2 cup brown rice; steamed asparagus spears drizzled with olive oil; salad with 1 1/2 cups spinach leaves tossed with sliced red peppers, red onion, 2 tablespoons avocado cubes and dressing made with 1/2 tablespoon olive oil and 1 teaspoon vinegar; 6 ounces red wine.
Why: Salmon is a top source of omega-3. Oregano, asparagus, red peppers, and onions all contain various antioxidants. Spinach does too, along with a small amount of omega-3. Brown rice is high in lignans, unlike packaged white rice, and that powdered sauce also contains omega-6. Avocado is a source of monounsaturated fat, as is olive oil, which may have additional unique anti-inflammatory properties. Wine contains polyphenols and has been linked to lower rates of inflammation.
Typical Choice: One cup of chocolate ice cream
Better Choice: One cup of sliced fresh peaches sprinkled with cinnamon
Why: Peaches contain carotenoids and flavonoids instead of the saturated fat found in ice cream; cinnamon packs polyphenols.
Typical American Diet: 2,583
Anti-Inflammation Diet: 1,543