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    Salt plays an important role in our daily diet. Even a small reduction(减少) in salt in the diet can be a big help to the heart. A new study used a computer model to predict -how just three grams less a day would affect heart disease in the United States.

    The result: Thirteen percent fewer heart attacks. Eight percent fewer strokes（中风）. Four percent fewer deaths. Eleven percent fewer new cases of heart disease. And two hundred forty billion dollars in health care savings. Researchers found it could prevent one hundred thousand heart attacks and ninety-two thousand deaths every year．

    The study is in the New England Journal of Medicine. Kirsten Bibbins-Domingo at the University of California San Francisco was the lead author. She says people would not even notice a difference in taste with three grams, or one-half teaspoon, less salt per day. The team also included researchers at Stanford and Columbia University.

    Each gram of salt contains four hundred milligrams of sodiu(钠), which is how foods may list their salt content．

    The government says the average American man eats ten grams of salt a day. The American Heart Association advises no more than three grams for healthy people. It says salt in the American diet has increased fifty percent since the nineteen seventies, while blood pressures have also risen. Less salt can mean a lower blood pressure.

    New York City Mayor Michael Bloomberg is leading an effort called the National Salt Reduction Initiative. The idea is to put pressure on food companies and restaurants. Critics call it government interference(干预).

    Mayor Bloomberg has already succeeded in other areas, like requiring fast food places in the city to list calorie information. Now a study by the Seattle Children's Research Institute shows that the calorie information on the menu can influence what parents order for their children. Ninety-nine parents of three to six year olds took part. Half had calories between the two groups for foods that the parents would have chosen for themselves. McDonald's menus clearly showing how many calories were in each food. Parents given the counts chose an average of one hundred two fewer calories when asked what they would order for their children. Yet there was no difference in calories between the two groups for foods that the parents would have chosen for themselves.

    Study leader Pooja Tandon says even small calorie reductions on a regular basis can prevent weight gain over time. The study was published in the journal Pediatrics.