DEAR DOCTOR K: I know lots of foods raise cholesterol levels. But are there any foods that lower cholesterol?

DEAR READER: Indeed there are. But before talking about them, it's worth saying a few words about foods that raise your cholesterol.

Except for a very few people who inherit genes that cause them to have high cholesterol, most of us who have had a "cholesterol problem" (which includes me) do it to ourselves by the foods we eat.

Foods with lots of cholesterol raise our blood cholesterol levels. But foods with lots of saturated fats and trans fats (the "bad fats") are even worse. They cause your liver to make lots of cholesterol.

Foods rich in saturated fats include whole milk, butter, cheese, ice cream, red meat and coconut products. Foods rich in trans fats include hard margarines, partially hydrogenated vegetable oils, many deep-fried fast foods and most commercial baked goods.

These are the foods you want to eat less of, to avoid raising your cholesterol. What about foods to eat more of, to lower your cholesterol? Some cholesterol-lowering foods have a lot of soluble fiber, which sticks to cholesterol in the gut. When that happens, the cholesterol is not easily digested, so it passes out of your body in a bowel movement instead of entering your blood. The same thing happens with foods rich in plant sterols and stanols. Other cholesterol-lowering foods are rich in the "good fats" (monounsaturated and polyunsaturated fats) that directly lower LDL (bad) cholesterol.

Here are five foods you can start with to get your cholesterol-busting under way:

- OATS. Choose oatmeal or a cold oat-based cereal such as Cheerios for breakfast. It gives you 1 to 2 grams of soluble fiber. Add a banana or some strawberries for another half-gram.

- BEANS. Beans are especially rich in soluble fiber. They also take a while for the body to digest, meaning you feel full longer after a meal. With so many choices - from navy and kidney beans to lentils, garbanzos, black-eyed peas and beyond - and so many ways to prepare them, beans are a very versatile food.

- NUTS. Eating almonds, walnuts, peanuts and other nuts is good for the heart. Eating 2 ounces of nuts a day can slightly lower LDL. And nuts have additional nutrients that protect the heart in other ways.

- FOODS FORTIFIED WITH STEROLS AND STANOLS. Companies are adding sterols and stanols to foods ranging from granola bars to orange juice and chocolate. They're also available as supplements.

- FATTY FISH. Eating fish two or three times a week can lower LDL in two ways: by replacing meat, which has LDL-boosting saturated fats, and by delivering LDL-lowering omega-3 fats. Omega-3s also reduce triglycerides, a type of fat in the bloodstream.

If you're buying packaged food at the market, check the Nutrition Facts label to see how much of each kind of good fat and bad fat, and how much fiber, are present. It's much easier to eat healthy today.

Dr. Komaroff is a physician and professor at Harvard Medical School. To send questions, go to AskDoctorK.com, or write: Ask Doctor K, 10 Shattuck St., Second Floor, Boston, MA 02115.