Heart disease is still the nation's No. 1 killer. Exactly what keeps your heart healthy is still a bit controversial, but what we do know is that being physically active, eating fruits and vegetables, reducing certain types of saturated fats and increasing "good" fats all help. Here are a few swaps that could help you have a healthier heart.

Snack on pistachios instead of potato chips.

Research in the Journal of the American College of Nutrition has shown that a four-week pistachio diet containing moderate amounts of heart-healthy fat decreases risk factors for heart disease with no weight gain. Another study, done at Penn State, compared two groups, one eating a cholesterol-lowering diet and another that added pistachios to the same diet. Researchers concluded that eating either 1.5 or 3 ounces of pistachios daily reduced the risk of cardiovascular disease by significantly reducing LDL (bad) cholesterol levels. In addition, the higher daily dose reduced lipoprotein ratios.

While pistachios are packed with fiber, vitamins and potassium, a mere half-ounce of pistachios (24 nuts) has approximately 85 calories. So eat them sparingly, account for them in your daily caloric budget or use them to replace high-calorie, high-fat foods like chips, which have about 150 calories per ounce.

Use 100 percent whole-grain bread instead of white bread.

A diet high in whole-grain foods is associated with a significantly lower risk of cardiovascular disease, including heart disease and stroke, according to an analysis by researchers at Wake Forest University School of Medicine. (Read more about whole grains at: www.dietdetective.com/content/view/1141/2.)

Consuming 2.5 servings of whole grains daily is associated with a 21 percent lower risk of cardiovascular disease, compared with consuming 0.2 servings. These results were published in the journal Nutrition, Metabolism & Cardiovascular Diseases. Make sure to look for "100 percent whole grain" on labels or for specific types of whole-grain flour, such as "whole wheat," as the first ingredient.

Cook vegetables in microwave bags instead of using oil and a regular pan.

Use Glad SimplyCooking Microwave Steaming Bags: Put your washed vegetables into the bag, seal it, place in the microwave, and minutes later you have steamed vegetables without adding water or oil. Vegetables are high in fiber, and a diet rich in fiber can help lower blood cholesterol and reduce your risk of heart disease.

Use skim milk instead of whole milk.

You don't have to switch all at once. Go from whole milk to 2 percent, then 1 percent, and before you know it, you'll be a skim milk aficionado. One cup of whole milk has almost 5 grams of saturated fat, whereas skim milk has only 0.125 grams, not to mention the calorie savings (146 calories per cup for whole milk vs. 83 calories for skim).

Use margarine spray instead of butter.

If you're looking to save calories and saturated fat, using a margarine spray such as I Can't Believe It's Not Butter or Smart Balance is a good way to start (10 calories per 10 sprays). Butter has 100 calories per tablespoon and contains more than 7 grams of saturated fat.

Use garlic instead of salt.

People who significantly cut back on salt could reduce their chances of developing cardiovascular disease by 25 percent, according to a report in the British Medical Journal. Furthermore, researchers found that lower salt intake could cut the risk of death from cardiovascular disease by up to 20 percent.

By using garlic instead of salt, you not only get the benefit of lower blood pressure, you also get the health perks of garlic, such as fighting cancer and possibly reducing the risk of cardiovascular disease by lowering total LDL (bad) cholesterol without affecting HDL (good) cholesterol.

Read a heart health guide instead of a "trashy" romance novel.

"The Healthy Heart Handbook for Women," published by the National Heart, Lung, and Blood Institute, includes statistics, quizzes and charts. It's free and a great resource. www.nhlbi.nih.gov/health/public/heart/other/hhw/hdbk_wmn.pdf.

Go for wild salmon instead of steak.

Instead of that big, thick steak, which has saturated fat and lots of calories, try wild salmon, which has high concentrations of omega-3s. One of the key benefits of omega-3 fatty acids is that they significantly reduce the risk for sudden death from cardiac arrhythmias, and deaths from many causes in patients with coronary heart disease.

Deliver your messages in person instead of e-mail or the phone.

Instead of sending an e-mail, calling or IMing your officemate or neighbor, try walking. Yes. Even a little exercise helps lower blood pressure.

A study in the Journal of Epidemiology and Community Health suggests that even low levels of weekly exercise drive down blood pressure and boost overall fitness. And while current recommendations are to get 30 minutes of moderately strenuous exercise on at least five days of the week, even a few minutes a day is better than nothing.

Use olive oil cooking spray or a cooking spray mister (www.misto.com) instead of regular cooking oil.

Avoiding certain saturated fats can be one of the keys to heart health (being a healthy weight and eating "right" also matter), so switching your current oil (e.g., palm or corn oil) to olive oil, which has some "good" fat, can help. The Food and Drug Administration actually lets olive oil manufacturers make a health claim stating that 2 tablespoons of olive oil daily "may reduce the risk of coronary heart disease."

However, just because olive oil is heart-healthy doesn't mean you can use it with impunity — it still has 120 calories per tablespoon. So use it to replace existing fat in your diet. And use it sparingly, or try a cooking mister or spray.

Charles Stuart Platkin is a nutrition and public-health advocate, and author of "Breaking the FAT Pattern" (Plume, 2006). Sign up for the free Diet Detective newsletter at www.dietdetective.com.