heart and blood vessel disorders
Overview of Coronary Artery Disease (CAD)
Prevention of CAD
Modifying risk factors of atherosclerosis can help prevent coronary artery disease. Some of these factors are interrelated, so that modifying one also modifies another. Smoking Cessation is most important. People who quit smoking decrease their risk of developing coronary artery disease by half compared with those who continue to smoke. How long people smoked before quitting does not matter. Quitting also decreases the risk of death after coronary artery bypass surgery or after a heart attack. Avoiding secondhand smoke is also important. Several changes are beneficial: Less saturated fat No trans fats More fruits and vegetables More fiber Moderate (if any) alcohol Less simple carbohydrates (such as, sugar, white bread, and white flour) Limiting the amount of fat to no more than 25 to 35% of daily calories is recommended to promote good health. However, some experts believe that fat must be limited to 10% of daily calories to reduce the risk of coronary artery disease. A low-fat diet also helps lower high total and LDL (the bad) cholesterol levels, another risk factor for coronary artery disease. The type of fat consumed is as important as the amount of fat. Thus, eating oily fish, such as salmon, which are high in omega-3 fats (good fats), regularly and strictly avoiding the more harmful trans fats are recommended. Trans fats are being removed from ingredients in many packaged food products, fast food sites, and restaurants. Eating at least five servings of fruits and vegetables daily can decrease the risk of coronary artery disease. Such foods contain many phytochemicals. Whether the phytochemicals are responsible for the risk reduction is unclear because people who consume such diets also tend to eat less fat, more fiber, and more foods containing vitamins C, D, and E. People who eat foods rich in a group of phytochemicals called flavonoids (found in red and purple grapes, red wine, and black teas) appear to have a lower risk of coronary artery disease. However, there is no clear cause-and-effect relationship. Some other factor in their life may account for the apparent lower risk. levels. Thus, soluble fiber may help people with Diabetes Mellitus (DM) reduce their risk of coronary artery disease. Insoluble fiber (which does not dissolve in liquid) is found in most grains and grain products and in fruits and vegetables such as apple skin, cabbage, beets, carrots, Brussels sprouts, turnips, and cauliflower. It also helps with digestive function. However, eating too much fiber can interfere with the absorption of certain vitamins and minerals. The diet should contain the recommended daily requirements of vitamins and minerals. Vitamin supplements are not considered an acceptable substitute for a healthy diet. The role of supplements in reducing the risk of coronary artery disease is somewhat controversial. Taking supplements ofvitamin Eor vitamin C does not seem to prevent coronary artery disease. Taking folate or vitamins B6 and B12 may lower homocysteine levels, but studies have not shown that taking these supplements decreases the risk of coronary artery disease. Limiting the amount of simple sugar carbohydrates (such as refined white flour, white rice, processed foods) and increasing the amount of whole grains may help reduce the risk of coronary artery disease because it reduces the risk of obesity and possibly of diabetes, which are also risk factors for coronary artery disease. Overall, people should maintain a healthy weight and eat a variety of foods. Several specific diets have been proposed to reduce the risk of heart disease or stroke. The Mediterranean diet appears to reduce the risk of coronary artery disease as well as the risk of further heart attacks in those who already have heart disease. According to theAmerican Heart Association, the Mediterranean diet consists of plenty of fruits, vegetables, nuts, seeds, bread and other grains, potatoes, beans, and olive oil. Dairy products, eggs, fish and poultry are eaten in low to moderate amounts. Fish and poultry are more common than red meat in this diet. It also centers on minimally processed, plant-based foods with fruit as a common dessert instead of sweets. Wine may be consumed in low to moderate amounts, usually with meals. There are three types of fat: Saturated Monounsaturated Polyunsaturated “Saturated” refers to the number of hydrogen atoms in a molecule of fat. Saturated fatscontain as many hydrogen atoms as they can. They are usually solid at room temperature. Saturated fats are present in meats, dairy products, and artificially hydrogenated vegetable oils. The more solid the product, the higher is the proportion of saturated fats. A diet high in saturated fats promotes coronary artery disease. Unsaturated fats(monounsaturated and polyunsaturated) do not contain as many hydrogen atoms as they could. Monounsaturated fats could contain one more hydrogen atom. They are usually liquid at room temperature but start to solidify in the refrigerator. Olive oil and canola oil are examples. Polyunsaturated fats could contain more than one additional hydrogen atom. These fats are usually liquid at room and refrigerator temperatures. They tend to become rancid at room temperature. Corn oil is an example. Other polyunsaturated fats include omega-3 fats, contained in deep-sea fatty fish (such as mackerel, salmon, and tuna), and omega-6 fats, contained in vegetable oils. Trans fatsare produced in a process called hydrogenation, in which hydrogen atoms are artificially added to polyunsaturated oils (“Trans” refers to where the hydrogen atoms are added to the fat molecule.). Oils containing trans fats may be used to make food products that do not become rancid and to make solid fat products, such as margarine. Trans fats are particularly common in commercial baked and fried foods, such as cookies, crackers, doughnuts, french fries, and other similar foods. Trans fats increase low-density lipoprotein (LDL—the bad) cholesterol levels and decrease high-density lipoprotein (HDL—the good) cholesterol levels, and these effects appear to increase the risk of coronary artery disease. Avoiding products that contain trans fats is wise. Trans fats are now listed on food labels. Also, if hydrogenated fat or partially hydrogenated fat is the first fat on the list of ingredients, the product contains trans fats. Some restaurants also provide information on which menu items contain trans fats. Some cities in the United States have barred restaurants from using trans fats in their food, and more cities are likely to follow this trend. The federal Food and Drug Administration has told manufacturers that they should remove trans fats from their products. The appearance of a margarine or oil can also help identify foods containing these fats—the softer or more liquid, the lower the trans fat content. For example, the trans fat content of tub margarines is lower than that of stick margarines. Some margarine products contain a plant sterol or stanol, which can lower total and LDL cholesterol levels. Plant sterols and stanols may have this effect because they are not absorbed well in the digestive tract and they interfere with the absorption of cholesterol. These margarine products have been approved as heart healthy foods when they are used as part of a healthy diet. These products are made from unsaturated fat, contain less saturated fat than butter, and do not contain trans fats. However, they are expensive. The ideal combination of types of fats is unknown. However, a diet high in monounsaturated or omega-3 fats and low in trans fats is probably desirable. People who are physically active are less likely to develop coronary artery disease and High Blood Pressure . Modifying the diet and engaging in physical activity can help control Obesity . Decreasing alcohol consumption can also help because alcohol is high in calories. A loss of even 10 to 20 pounds (4½ to 9 kilograms) can reduce the risk of coronary artery disease. High total and LDL (the bad) cholesterol levels can be lowered by exercising and by quitting smoking as well as by reducing the amount of fat in the diet. Drugs that lower levels of total and LDL cholesterol in the blood ( Lipid-lowering drugs ) may be used. The benefits of lowering cholesterol levels are greatest in people with other risk factors, such as smoking, high blood pressure, obesity, and physical inactivity. Increasing the level of HDL (the good) cholesterol also helps reduce the risk of coronary artery disease. The same lifestyle changes that lower total and LDL cholesterol levels can help increase HDL cholesterol levels. Certain drugs can also increase HDL levels, but it is not clear whether using drugs to increase HDL levels is helpful. For people who are overweight, losing weight can also help. Lowering High Blood Pressure reduces the risk of coronary artery disease. Treatment of high blood pressure begins with lifestyle changes: eating a healthy diet that is low in salt and, if needed, losing weight and increasing physical activity. Good control of Diabetes Mellitus (DM) reduces the risk of some complications of diabetes, but the effects of such control on the development of coronary artery disease are less clear. Good control of diabetes may also reduce the risk of complications of coronary artery disease. Aspirin, sometimes recommended in the past for people who have never had coronary artery disease, is not currently recommended for such people. 