Thanks to the men and women in white lab coats who've done countless hours of research, we now know that there are specific preventive measures we can take to lower our risk for many diseases as we age. Here are 10 key things you can start doing right away to help keep you healthy and feeling young.

Toss the smokes. Lung cancer, heart disease, stroke, high blood pressure, osteoporosis. The list of age related diseases that smokers are at higher risk for goes on and on. Not to mention the wrinkles and stained teeth that make you look far older than your years. If you don't smoke, raise your right hand and swear you never will. Then give yourself a pat on the back. If you do smoke stop. "Without a doubt, it's one of the best things you can do for your health," says Elizabeth Ross, M.D., a cardiologist at Washington Hospital Center in Washington, D.C.; spokesperson for the American Heart Association; and author of Healing the Female Heart. Within minutes of puffing your final cigarette, your blood pressure and pulse rate drop to normal. And after just 24 hours, your risk of having a heart attack decreases.

Add activity. Close to five minion American adults say they don't do anything physically active in their leisure time. Now that's a lot of couch potatoes. And it turns out that more women are inactive than men. Everyone knows exercise is good for you so why are so many women still stuck on the sofa? Perhaps you haven't found a fun activity that keeps you coming back for more. Or maybe you think you don't have the time. But it takes a lot less time than you probably realize.

"You don't have to go to a gym every day or become a marathon runner to get the benefits of exercise," Dr. Buring says. "The current recommendation for physical activity is something that virtually all of us can do." That's 30 minutes of accumulated moderate physical activity most days of the week. Walking the dog, gardening, housework they all count.

Need another reason to trade in your recliner for a treadmill? How about 250,000 reasons? That's how many deaths per year in this country can be attributed to a lack of regular physical activity. In fact, regular exercise helps prevent everything from heart disease and diabetes to breast cancer and osteoporosis.

Control your weight. It's no secret that we tend to put on pounds as we grow older. A growing middle may seem like a harmless, natural part of aging, but it's not. "In this country, we gain an average of 7 pounds a decade," Dr. Buring says.

That adds up fast. If you weighed 125 at age 20, that means you'll tip the scale at 160 by the time you're 70. That rate of weight gain puts you at risk for a number of diseases including diabetes, heart disease, arthritis, and even gallstones.

Losing weight isn't easy. So your best bet is not to gain it in the first place. "Focus on maintaining your weight rather than trying to lose the extra pounds after you've already gained them," Dr. Buring says.

If you've already put on some pounds, try losing just 10. Even small reductions can go a long way in helping improve your condition if you have a problem like arthritis or high blood pressure, Dr. Buring says.

Pile your plate with fruits and veggies. That's right. One key to living a long, diseasefree life can be found in the produce section of any grocery store. In fact, a study of 52 Italians aged 70 and older found that the healthy one , hundred and somethings ate more than twice as many vegetables as the younger folks.

That's not surprising since eating five servings of fruits and vegetables a day is associated with lower risks of several diseases, including cancer and stroke. And researchers have identified all sorts of healthy components in our produce. Not only are fruits and vegetables a natural source of antioxidants, vitamins, minerals, and fiber they also contain phytonutrients like quercetin, lycopene, flavonolds, and ellagic acid, which are potential heart protectors and cancer fighters.

Eat a low fat diet. Too much fat does a lot of nasty things to our bodies. First, it can clog up the arteries in our hearts and block blood vessels in our brains, putting us at risk for heart disease and stroke. Excess fat can also overstimulate our gallbladders and create the right conditions for painful gallstones. And of course, too much fat can make us, well, fat, which increases our risk for other diseases like cancer and diabetes.

Most experts agree that a low fat diet should get no more than 25 percent (and preferably less) of its calories from fat. But not all fats are bad. The main one to limit in your diet is saturated fat, found in foods like meat, butter, and dairy products. Researchers say that the best way to cut down on saturated fat is to Emit meat servings to 3 or 4 ounces a day, use little or no butter, switch to low fat dairy foods, and cook with corn, canola, or olive oil.

Other fats to be wary of include the trans fatty acids found mostly in margarine and prepackaged snacks. They may be just as unhealthy for our hearts as saturated fat. You can cut your trans fatty acids by using trans free margarine (partially hydrogenated oils are not listed as an ingredient) instead of regular margarine and by limiting the amount of snack foods you eat that contain partially hydrogenated oil.

Fill up on fiber. Eating a high fiber diet may lower your risk for several diseases, including heart disease, diabetes, high blood pressure, obesity, and diverticulosis. And several small studies suggest that filling up on fiber can lower your risk of colon cancer. How does fiber protect against such a variety of diseases? For one thing, it acts like a sponge as it passes through our bodies, soaking up potentially harmful substances like cholesterol and binding to extra estrogen in the digestive tract, then removing them in our stool. Fiber also fills us up so we eat less.

The problem is that most people only get 11 to 13 grams of fiber a day that's about half of the 25 to 35 grams experts recommend. To give your plate a fiber face-lift, add more foods like fruits, vegetables, beans, and whole-grain breads, cereals, rice, and pasta.