Public schools across the country have been on a health look since 2010. Thanks to a new law, students said goodbye to unhealthy food and hello to better eating habits in school. They also have been exercising more during the school day.

It's up to schools to decide how they follow the law. Many places require schools to provide healthy choices for lunch. In Tennessee, most schools removed（移除）sugary snacks and soft drinks from vending machines（自动贩卖机）. Instead of them, there are more nutritious（有营养的）choices, such as granola bars, nuts, water, and juice.

In Florida, Missouri, and Texas, some schools have rules that ban（禁止）desserts such as cupcakes and lollipops from parties. Instead, school officials encourage teachers and parents to provide more nutritious food.

To get kids to exercise more, the northwestern Minnesota district of Perham Dent added more physical activity to the school day. Many schools also make sure that kids have break every day.

The goals of the law are to improve good health and to reduce obesity（肥胖）. Obesity is the condition of being very overweight. Being obese can lead to serious health problems later in life. Experts say the number of children aged 6-11 years old who were obese more than doubled from 1980 to 2012, and the number of obese young people aged 12-19 years old have increased 4 times in the same time period.

“We know that adults who are very overweight get sick more often and lose time at work.” Julia Lear, the director of the Center for Health and Health Care in Schools, told WR News. “The best thing to do is to get kids in the habit of getting lots of exercise and eating healthy meals.”

Life is full of rules including communication, traffic, health and so on. There are five rules for a healthy life that may help you a lot.

【小题1】

Sure, it is comfortable to sit on the sofa and watch TV. But doctors say you should get off the sofa. To keep fit, you have to walk at least 10,000 steps every day. And if you sit all day, you will become fat and it will influence your health.

【小题2】

It is important for you to eat food that is fresh and natural, for example, fruit and vegetables. As we know, fast food is unhealthy. So you should only have it once in a while. Eating too much of the wrong food will do harm to your health.

【小题3】

It is very important for teenagers to get enough sleep. At weekends, you have gotten more time, so use it not just for playing games, but for rest too. If you really want to be happy, calm and relaxed, you must have a good sleep.

【小题4】

Many people believe that happiness is important for our health. If you are worried about something, talk to your parents or your teachers. You should forget the trouble and find out something that makes you happy. To be happy all the time, do not dwell (纠结) on one thing, it is not a big deal, our happiness is the most important.

【小题5】

Smoking isn’t cool. It is dangerous. Think about how your family and friends will feel, and think about what it will do to your health. Smoking can cause lots of diseases, the most serious can cause cancer even death.

You might think that drinking fruit juice is healthy. But that’s not quite true. A study (研究) shows that drinking too much juice—even 100% fruit juice—will do great harm to your health and can even make you die early.

This is because these drinks have a lot of sugar. Scientists said drinking too much fruit juice is just like drinking too much soda (汽水) —they both have a lot of sugar. Eating too much sweet food can cause many health problems, such as getting fat and heart disease. Fruit juice has vitamins (维生素), but there are very few vitamins in it.

In the study, both soda and 100% fruit juice are “sweet drinks”. Scientists found that if people get 10% or more of their energy from sweet drinks every day, they may die from heart disease or other diseases. Jean Welsh, one of the scientists in the study, told CNN, “People should drink less sweet drinks, whether soda or fruit juice.”

Does this mean that eating fruit is also unhealthy? Fruit is still fine. When you eat 100g of fruit, you’re getting less sugar than if you drink 100g of juice, because the fruit has lots of fiber (纤维). This fiber is also good for our health. It’s better to eat the whole fruit instead of fruit juice.