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Cholesterol and Heart Disease Do you know your cholesterol level Many people don’’t. A high level of cholesterol in the blood is an important risk factor for heart disease. Some people say that the danger of heart disease is exaggerated. However, heart disease is a main cause of death in developed countries. Every year more than one million Americans have heart attacks, and half of them die. People With heart disease suffer chest pains that make simple activities, such as walking, shaving, or taking a shower, difficult. Research has proven that cholesterol levels are Connected with heart disease. One project in Massachusetts has studied the same group of men and women since 1948. The researchers have found that the people who have high levels of cholesterol have more heart attacks. A natural substance in the blood, cholesterol comes from the liver. The amount of cholesterol is affected by diet and by physical qualities we inherit from our parents. One kind of cholesterol sticks fat to the walls of arteries, making them smaller and finally blocking them. It produces a condition called "hardening of the arteries," which causes heart attacks. With tiny cameras, doctors can see blood circulating through the heart valves. Angiograms (血管造影照片) are x-rays of the heart arteries. They show fat deposits and blockages caused by high cholesterol. Heart disease begins in children as young as 3 years old. It occurs earlier in boys than in girls. Nearly half of teenagers have some fat deposits on their artery walls. Heart disease develops faster if we have high cholesterol levels and also smoke. What is a safe level of cholesterol Adults have a high risk of heart attack if their cholesterol level is above 240 milligrams per deciliter (1/10 公升) of blood. Below 200 is better. In the Massachusetts study, no one with a cholesterol level below 150 has ever had a heart attack. However, about half of American adults have cholesterol levels above 200. To lower our cholesterol level, we must change our eating habits. Anything that comes from an animal is high in fat and high in cholesterol. The American Heart Association National Cholesterol Education Program says that fat should be no more than 30 percent of our diet. Blood cholesterol levels start to fall after 2 to 3 weeks of following a low-cholesterol, low-fat diet. Dietary changes alone can result in a 10 percent reduction of the average person’’s cholesterol level. Aerobic exercise helps, too. Artery blockage can be reduced by as much as 40 percent through changes in diet and amount of exercise. We must educate everyone, including children in elementary schools. We must teach them responsibility for their health through classes in nutrition and aerobic exercise. For example, the smart snack is fruit. Children must be served fruit in the school cafeteria, along with low-fat meals. Schools must send recipes home with the children. Parents must include children in planning and preparing meals and shopping for food. Adults, including persons over the age of sixty five, can lower their cholesterol by 30 or 40 percent. It is never too late to change. One man began his health program when he was seventy- three. By the time he was seventy-seven, he had lowered his arterial blockage from 50 percent to 13 percent and his cholesterol from 320 to 145 without drugs. He went on a vegetarian diet with only 10 percent fat, plus programs to reduce stress and get more exercise. A low-cholesterol diet that cuts out most animal products and high-fat vegetables may be unfamiliar to people. The Heart Association says to use no added fat of any kind. Don’t fry food in oil. Cook it in water, vinegar, or vegetable water. Learn about grains and vegetables. Avoid egg yolks (the yellow part of the egg). Eat potatoes, beans, low fat vegetables, and fruit. People often complain about low-fat diets before they have had time to get used to them. Food can taste good without cream, butter, and salt. You can use olive oil, mustard, fresh herbs, or yogurt instead. A new diet can cause general anxiety, when people feel worried and nervous about what is going to happen. They must learn to deal with the changes in their lives. Sometimes major changes in diet or lifestyle are easier than minor ones because the results are bigger and faster. Fast results encourage us. How can you control the amount of fat in your diet if you eat in restaurants Restaurants must provide healthy meals that are low in fat, salt, and cholesterol. A diet is a personal thing. Restaurant owners should not make customers feel embarrassed because they want to follow a diet that is good for them. Restaurant owners must learn to give equal service to customers on a healthy diet. Some restaurants have items on the menu marked with a heart to show that they are low in fat, cholesterol, salt, or sugar. A few restaurants serve only these recipes. Heart disease causes one out of every four deaths in East Harlem in New York City. The East Harlem Healthy Heart Program is an educational program. It has 2 goals: to get people to change their diets and to find volunteers to help run educational activities. One way it educates is by street shows. Actors wear costumes and carry big pieces of plastic fat. They entertain so people will listen. Groups of children perform songs and dances that educate people about heart disease and diet. Volunteers lead walking and exercise groups to show people how to begin exercising. Volunteers also stand in supermarkets to suggest healthy food choices to shoppers. The volunteers have shoppers taste two kinds of milk to see which tastes better. Most people are surprised that the low-fat milk tastes better than the whole milk. Shoppers are encouraged to buy low-fat milk instead of whole milk. Education costs money, but it also brings results. In 1983, only 35 percent of the American public knew their cholesterol levels. By 1990, 65 percent of the people had had theirs checked. People feel better if they lower their cholesterol through diet. Healthy people are more confident. They are more attractive to themselves, as well as to others. Their friends stare at them because they look so healthy. We can prevent heart disease by living a healthful lifestyle and eating the right kind of diet. If people don’’t do this, two out of three men and women in America will eventually get heart disease. More than twice as many people had their blood cholesterol levels checked in 1990 as in 1983 .