Clean Your Filters

A few times each year, you swing your car into a repair shop for service. Inevitably, the mechanic trots over with your air filter to show you how filthy it is. "See," he'll say, acting as bummed as you are. "Better replace it."

You don't have that luxury with your body, but your lungs breathe in the same stuff your engine does, and your liver and kidneys can become as gummed up as any oil filter. These organs, along with your gastrointestinal tract and lymphatic system, cleanse your blood and sift out waste. Ignoring them can lead to everything from hypertension to asthma. But while you can't do much for your lymphatic system — it's self-cleaning — you can take steps to keep the other four clear. After all, replacements are very hard to come by.

Filter 1: Liver
Your multifunctional marvel

Think your liver is just there for you to abuse at happy hour? Well go easy on it, because in addition to processing booze, this 3 ½-pound gland — the largest in your body — has at least 250 functions. Primarily, it filters bacteria and pollutants from your blood. It also produces bile, a viscous goo that breaks down fat for digestion and absorption. "These functions begin to suffer when alcohol injures your liver or a poor diet causes extra fat to build up in your liver," says Paul Martin, M.D., the chief of hepatology at the University of Miami. When fatty liver occurs in people who don't drink heavily, it's associated with the same risk factors as those of metabolic syndrome: obesity, diabetes, and high triglyceride levels.

Keep it clear: Hitting the gym for an extra 10 minutes a day helps ensure that your liver stays on top of its responsibilities. In a 2009 study in Hepatology, people with nonalcoholic fatty liver disease who increased their exercise by 60 minutes a week for 3 months reduced their levels of four enzymes that indicate liver problems. "Exercise removes fat from the liver," says study author Jacob George, M.D., a professor of gastroenterology and hepatic medicine at the University of Sydney.

But you can easily undo your gains if you drink too much. While the occasional beer is fine — especially if it's one of the best beers in America — avoid binges of five or more drinks on a single occasion. And be careful about what you consider to be "a drink." One standard drink contains 0.6 ounces of alcohol, but a 2008 study from the Alcohol Research Group of the Public Health Institute found that in bars, the average glass of wine contains 43 percent more alcohol than that 0.6 ounces. The average draft beer has 22 percent more, and mixed drinks contain 32 percent more. So even if you limit the number of drinks, you could still be imbibing more alcohol than you intended to.

Filter 2: Kidneys
The blood balancers

Your kidneys are tireless. Every day they remove 2 quarts of waste and extra water from your blood. This process helps regulate blood pressure by extracting matter from your blood, which lowers your blood volume and, in turn, keeps the stress on your blood vessels and heart in check. The kidneys also balance the electrolytes in your body. Too much sodium, for instance, can lead to hypertension, and high potassium can cause abnormal heart rhythms, says Bryan Becker, M.D., a professor of internal medicine at the University of Wisconsin. Signs your kidneys may not be operating at peak performance include pinkish urine, foot or hand swelling, and persistent lower-back pain.

Keep them clear: Coming up short in the H2O department can lead to cell damage as the kidneys struggle to balance out the fluids in your body. Drink at least 3 quarts of water each day. A steady influx of water also helps to keep kidney stones from forming. These hard masses develop when calcium combines with either oxalate, phosphate, or other chemicals to form small crystals. If the crystals bind together, they can restrict the flow of fluids through your kidneys and cause severe — make that excruciating — pain. In addition to your 3-quart quota, add a glass of orange juice to your daily fluid intake. "Orange juice boosts citrate levels in your urine, reducing the crystallization and lowering the calcium available for binding," says Clarita Odvina, M.D., an associate professor of internal medicine at the University of Texas Southwestern Medical Center. Learn why you should have your OJ with oatmeal and discover 12 other health-boosting food pairings.

Filter 3: Lungs
Bad-air battlers

Here's a scary thought: Your lungs are the only internal organs that are continuously exposed to the external environment. Every breath you take brings in whatever debris happens to be floating in front of your face.

To deal with that floating junk, your lungs are lined with hairlike cilia, which sweep out the pollutants, bacteria, and viruses that you breathe in. Your lungs also perform the most essential task of extracting oxygen from the air and swapping it for carbon dioxide. Continued exposure to airborne gunk, however, can interfere with these processes, causing inflammation that may trigger bronchitis and asthmalike symptoms.

Keep them clear: Pick some apples. People who ate the most apples were 33 percent less likely to have a chronic phlegmy cough than those who ate the least, according to a National Institutes of Health study. The pectin and antioxidants in the peels can reduce inflammation in your lungs. Click here to read about 15 more powerfoods that cure. Also, stay inside when ozone levels are high. This pollutant causes inflammation that can narrow your airways. "If you're unusually winded after a run, you could be sensitive to ozone," says Norman Edelman, M.D., the chief medical officer of the American Lung Association. Check out daily ozone levels at airnow.gov, and work out indoors when the Air Quality Index is moderate or higher.

Filter 4: Gastrointestinal tract
The food processor

You may not know how to deal with that pizza-and-cake dinner you downed, but your body does. Your GI tract runs from your esophagus down into your stomach, small intestine, and colon, and separates what you need — protein, carbohydrates, fat, vitamins, and minerals — from what you don't. Any problems with absorption, obstruction, or movement can prevent your body from soaking up nutrients, says Brett Neustater, M.D., a gastroenterologist with the GI Group of South Florida. These problems can also cause serious discomfort. Look out for heartburn, bloating, and abdominal pain.

Keep it clear: While occasional flare-ups are usually harmless, frequent bouts of heartburn (more than twice a week) can scar your esophagus, causing food to stick on the way down. Taking antacids may help with the pain, but they won't prevent the attacks. If you're dealing with chronic heartburn, assess your diet. "Cut out trigger foods, and then reintroduce them after a week or so in smaller amounts," says Dr. Neustater. Common heartburn triggers include caffeine, onions, chocolate, citrus fruits, garlic, and tomatoes. If your symptoms persist, see your doctor to rule out a more serious problem.

Hernias can also sabotage your GI tract. They occur when part of an internal organ, most often the intestines, protrudes into and obstructs your abdominal muscles, sometimes as a result of excessive straining while lifting. "Before you lift, brace your stomach like you're about to be punched but are still able to breathe," says Pete McCall, M.S., C.S.C.S., an exercise physiologist with the American Council on Exercise. This supports and trains the muscles that line your abdominal wall. Plank exercises can also help strengthen your abs and could reduce the chances of a hernia. Use this plan to build a rock-solid core.
More Links:
6 Body Parts You Can Repair Yourself
Dr. Oz's 25 Greatest Health Tips
17 Problems You Can Fix Right Now
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