Obesity(肥胖) in children and adolescents is rising at an alarming rate. Currently over 15% of young people over 6 years old are obese, and obesity is also increasing among children aged 5 and younger. Children are considered to be overweight if the BMI(Body Mass Index) is over 85% of the weight group in their age and categories. If it is 95% and over, they are considered to be obese. Adolescents are generally judged according to criteria(标准) for obesity, although there are other considerations in this population, for many factors will affect the result of these measurements. Causes and Risk Factors for Obesity in Children Lifestyle Factors. Without educational or parental guidance, children are extremely greatly exposed to the cultural pressures that are largely responsible for growth of the obesity. Neither the media nor the educational system has strong programs that encourage healthy way of life, including exercise and healthy foods. The following are some specific problems created by the culture: ﹡Too much television watching plays an important role in obesity in children. Not only is it a passive activity, but television also offers countless temptations(诱惑) with its advertisements for fast foods, sugar cereals, and unhealthy snacks. In one study obesity rate were lowest in children who watched television one hour or less a day and highest in those who watched four or more hours. ﹡Sugar, particularly from soda, other sweet drinks, and fruit juice, may be major contributors to childhood obesity. One study reported that drinking soda regularly increases a child’s risk for obesity by 60%. ﹡Less physical exercise and greater sitting activities play another significant role in obesity in children. A high level of physical activity – not just using up energy – is important for weight control in young people. Family History. Parental obesity more than doubles the risk that a young child, whether thin or overweight, will become obese as an . In older children and agers, obesity in parents starts to affect less as a predictor(预言) for body weight than their own weight. The risk may be due to environmental or genetic factors, or both. Ethnic and Socioeconomic Factors. As in populations, children from lower socioeconomic groups and minority populations are at higher risk for obesity. For example, among young Mexican Americans and African Americans, there has been an increase in overweight trend of about 13% to over 23%. 69.What’s the main idea of the passage? ______________. A. The trend of obesity B. Causes of obesity C. Fight against obesity D. Obesity in children 70.How many main factors leading to obesity in children are mentioned? A. 2 B. 3 C. 4 D. 5 71.According to the passage, which of the following children is most likely to be obese? A. A 5-year-old child whose parents are overweight. B. A 16-year-old ager whose parents are obese. C. A child who watches TV one hour per day. D. A child who take regular exercise. 72.Which of the following is NOT true? A. Parents should give some guidance on healthy lifestyles. B. Watching TV four hours a day will surely lead to obesity in children. C. Children from minority populations are more likely to be obese. D. Children should take more physical exercises.