VOA听力9篇文章.docx

1. Foods and HealthThis is the VOA Special English Health Report.Experts say the food people eat greatly affects their health. They say that some foods are especially good for preventing disease. Many foods contain substances that protect against tissue damage. One of these is tomatoes. The substance lycopene is released when tomatoes are cooked. Lycopene helps reduce the risk of developing cancer in the digestive system, which processes food.The dark green vegetable spinach contains folic acid that prevents problems in developing fetuses. It also lowers blood levels of homocysteine. High homocysteine levels have been linked to heart attacks and strokes. Another vegetable, broccoli, can help protect against cancers of the breast, colon and stomach.Oats help lower blood pressure and protect against heart disease. They also may improve the levels of sugar in the blood. This reduces the chance of developing the disease, diabetes.Fish that contain omega three fatty acids help prevent blockages in the arteries. Omega three also lowers bad cholesterol and may protect brain cells from diseases like Alzheimer's. Fish that provide a lot of omega three acids are salmon, herring, mackerel and bluefish.Garlic may help protect the heart by reducing cholesterol and making the blood less sticky. Health experts also suggest cooking with olive oil because it also has been shown to help prevent cancer and heart disease.Studies show that drinking green tea may help prevent cancer of the liver and stomach. Green tea also slows the growth of bacteria in the mouth. Blueberries have been shown to help protect against heart disease and cancer. They can also help prevent some infections by preventing the bacteria from attacking the bladder.Experts say the skins of red grapes contain substances that increase the good kind of cholesterol in the blood. To get this protection, you can drink red wine... but not more than a few glasses a week. Drinking too much alcohol can be dangerous!Eating too much chocolate can increase weight. But recent studies have shown that substances in chocolate can help prevent heart attacks and cancer. They have also shown that chocolate is not as bad for the teeth as had been thought. The experts say the best chocolate to eat is the dark kind because it contains the most healthful substances.This VOA Special English Health Report was written by Nancy Steinbach.2. Study of Cousins Who MarryThis is the VOA Special English Health Report.Sometimes people who are first cousins get married. Two people are first cousins if their mothers are sisters, or their fathers are brothers, or one's mother and the other's father are brother and sister. American researchers now say it is not as dangerous as had been thought for first cousins to have children. Graphic ImageA new study says that first cousins are only a little more likely than others to have a child with a serious physical or mental problem, or a genetic disease. It says the chance that a child of unrelated parents will be born with a serious problem is between three and four percent.The risk for first cousins is increased by between two and three percent, to as much as seven percent. One researcher says this means about ninety-three percent of the children of first cousins are normal.The small increase in risk exists because people in the same family may carry the same genes that cause disease. Scientists say at least five-thousand diseases are caused by these genes. If both parents have a harmful gene, it is more likely that the gene will be passed on to their child. People who are not related share fewer genes, so their chance of passing such a sickness on to their children is lower.A committee from the National Society of Genetic Counselors reported the results of their investigation in "The Journal of Genetic Counseling." The group examined six major studies done between Nineteen-Sixty-Five and Two-Thousand involving thousands of births. The group began the investigation after learning that some genetic counselors gave wrong information to people who wanted to know if first cousins could safely have children.The group said in its report that no genetic tests are needed before first cousins have a child. Their report also noted that Americans fear such marriages more than people in other parts of the world.Marriages between first cousins are illegal in at least twenty-four American states. However, no countries in Europe have such laws. And marriages between cousins are desirable in many parts of the Middle East, Africa and Asia. The researchers say their study shows that such laws in the United States should be changed.This VOA Special English Health Report was written by Nancy Steinbach.3. WalkingThis is the VOA Special English Health Report.Researchers agree that intense physical exercise is not the only way to gain better health. Studies show that walking several times a week can lower the risk o。