Cholesterol is a type of fat that your body needs, among other things, to produce cell membranes and hormones. Your body is capable of producing all the cholesterol it needs. Additional cholesterol in our bodies comes from eating foods high in saturated fats, such as meat, high-fat dairy, and eggs. Also, some people have a genetic disposition to high cholesterol meaning food is not the issue but how their body manufacturers cholesterol.
Excess cholesterol builds up as fatty deposits or "plaque" in your arteries. Plaque buildup reduces blood flow through your veins, making your heart work harder and increasing your risk of heart disease and stroke.
There are a few approaches you can take to lowering your cholesterol. The American Heart Association recommends ways to lower your cholesterol by changes to your diet, by taking medication, being more physically active, and by making lifestyle changes. 
This food is a good source of polyunsaturated and monounsaturated fats, and has no cholesterol
Eating to lower your cholesterol. Most of the cholesterol you need is made by your body. However, food products from animals contain additional cholesterol as well. The foods include meats, poultry, shellfish, eggs, butter, cheese, and milk. Any type of food that contains saturated or trans fat causes your body to make more cholesterol.
The American Heart Association recommends that you keep your intake of fat between 25 and 35% of your daily calories. Also, limit your intake of cholesterol from food to less than 300 mg a day. If your cholesterol is high, the recommended amount is less than 200 mg per day. Lastly, be sure to get at least 25 to 30 grams of fiber each day. Whole grains, fruits, vegetables, and legumes are good sources of fiber.
The Mayo Clinic came up with a list of the top 5 foods to lower your cholesterol. 
Oatmeal and oat bran contain soluble fiber, which reduces your LDL cholesterol. Soluble fiber is also found in kidney beans, apples, pears, barley, and prunes. Soluble fiber also appears to reduce the absorption of cholesterol in your intestines.
Walnuts and almonds are rich in polyunsaturated fatty acids and have noted for keeping blood vessels healthy and elastic. Be careful not to eat too many nuts though. They are high in calories, so just one handful will be enough. As with any food, eating too much of it can make you overweight, and being overweight puts you at higher risk for heart disease. The key, just like with anything else, is to find a balance.
Fish and omega-3 fatty acid reduce blood pressure and the risk of blood clots. Doctors recommend having at least 2 servings of fish each week. The fish with the highest levels of omega-3 fatty acid are in mackerel, lake trout, herring, sardines, albacore tuna and salmon. To maintain the health benefits of fish, you’ll need to grill or bake the fish. If you don’t like fish, you can also get omega-3 fatty acids from foods like ground flaxseed or canola oil.
Olive oil contains antioxidants that can lower your LDL (“bad”) cholesterol without changing your HDL (“good”) cholesterol. The FDA recommends about 2 tablespoons, or 23 grams, of olive oil a day to benefit from its heart-healthy benefits. Some research suggests that the cholesterol-lowering effects of olive oil are even better if you choose extra-virgin olive oil.
Foods fortified with plant sterols or stanols, which are found in plants and help block the absorption of cholesterol, can help reduce LDL cholesterol by more than 10%.
Taking medication. Your doctor will judge if you should take medication. He or she may want you to try to make diet and lifestyle changes before going on medication. Depending on the level of your LDL (bad) cholesterol and your other risk factors for cardiovascular disease, your doctor may decide that you need to start taking medication at the same time you start making lifestyle changes.
Be more physically active. Physical inactivity is a major risk factor for heart disease. The American Heart Association recommends getting at least 30 minutes of physical activity more days that not. You can also break up the half hour into 10 or 15 minute sessions. For some people, regular exercise affects blood cholesterol level by increasing levels of HDL, which is linked to a lower risk of heart disease. Physical activity can also help control some of the other risks of heart disease, such as being over weight, diabetes, and high blood pressure.
Remember to eat a heart-healthy diet. This means a diet rich in vegetables, fruits, whole grains, high-fiber foods, leans meats and poultry, fish, and fat-free or low-fat dairy products. Moderation is key with foods that are high in saturated fat, such as meat and some dairy products.
Start exercising. When you exercise, your blood pumps faster and the HDL cholesterol in your blood carries away the LDL cholesterol from your arteries. Get moving for at least 30 minutes more days of the week than not. Do whatever kind of physical activity you enjoy – walking, biking, swimming, jogging, or dancing.
Stop smoking.Smoking reduces the amount of HDL cholesterol in your blood. Smoking also increases the tendencies for your blood to clot. If you smoke, your cholesterol level is more of a good reason to quit.
Remember that there is “good” and “bad” cholesterol. HDL (high-density lipoproteins) is the “good” cholesterol. HDL carries harmful plaque buildup out of the arteries. A high HDL level means healthy arteries; too low an HDL level is a risk factor for heart disease and stroke. LDL (low-density lipoproteins) is the “bad” cholesterol that causes heart attacks and strokes. A high level of LDL cholesterol in the blood signifies clogged arteries, the condition also known as arteriosclerosis. Clogged vessels can cause heart attacks if they block the flow of blood to the heart, and stroke if they block blood flow to the brain. 
It can be difficult to get and maintain the motivation to make these healthy changes. The Healthy Monday Campaign encourages people to use Monday as the day to commit to a healthier life. They encourage people to pick up a healthy habit or to drop an unhealthy one. That way, instead of waiting until New Years or your birthday, you have 52 chances each year, thereby increasing your chance of success!
Polyunsaturated and monounsaturated fats are the healthy fats that you should have. They actually can help lower the bad cholesterol.
Take care of high cholesterol as soon as possible. Not doing so could put you at greater risk of suffering from a heart attack, blood clots, or other heart problems.