阅读基础如滴水穿石，连载考研英语阅读篇章，希望大家能保持阅读好习惯。
考研英语阅读篇章: 怎么吃才能保持身体健康
British nutritionists threw down the gauntlet to dietary guidelines in April by declaring seven daily portions of fresh fruit and vegetables, rather than the recommended five, were the key to health.
英国营养学家在四月份向既定的食谱指南发起挑战，宣称保持身体健康的关键是每日七种蔬果搭配而不是以往推荐的五种蔬果。
But a new foray(突袭，侵略) into the arena of sound eating says the famous five-a-day recommendation made by the UN's World Health Organisation in 2003 should be fine.
Researchers in China and the United States trawled through 16 published investigations into diet and health involving more than 830,000 participants, who were followed for periods ranging from four and a half years to 26 years.
Every additional daily serving of fruit and vegetables reduced the average risk of premature death from all causes by five percent, the scientists found.
Over the period of the studies, 56,000 of the participants died, researchers said.
In the case of death from a heart attack or a stroke, each additional serving curbed risk by four percent.
But there was no evidence of an additional fall in risk beyond five portions, according to the review, published online Tuesday by the British Medical Journal (BMJ).
"We found a threshold of around five servings a day of fruit and vegetables, after which the risk of death did not reduce further," said the investigators, led by Frank Hu of the Harvard School of Public Health in Boston, Massachusetts.
High consumption of fruit and veg did not translate into a significant reduction in the risk of death from cancer, the study also found.
In addition to advising patients about the virtues of healthy eating, doctors should also push home the message about risks from obesity, inactivity, smoking and excessive drinking, said the paper.