It’s hard to turn down junk food. However, eating too much is bad for your body, especially if you’re between the ages of 10 and 19. “Junk food shapes teenage brains in ways that make their ability to think, learn and remember weaker. It can also make it harder to control bad behaviors. It may even up a teen’s risk of mental (精神上的) problems,” said Amy Reichelt, a scientist at Western University, Canada.

Reichelt and two other researchers reviewed more than 100 studies about how poor food choices can make a big difference to teenage brains. They found teenagers are more sensitive (敏感的) than any other age group to foods with a lot of fat and sugar, as their brains are not yet fully formed.

Teenage brains are still developing the ability to notice risks and control actions. The prefrontal cortex (前额皮质) is the part of the brain tells us we shouldn’t eat chips all the time and helps us control ourselves. However, this part doesn’t fully develop until we are in our early 20s. At the same time, teen brains get more excited from prizes. The parts of the brain that make us feel good when we do something happy—like eating tasty foods—are fully developed by the teen years.

As a result, the teen brain has two hits against it when it comes to refusing junk food. Reichelt and her team did an experiment using mice, whose brains develop much like our own. They discovered that “teenage” mice that had high-fat foods performed worse on memory tests than those eating normal foods.

So, what’s the best way to say no to junk food? The answer is exercise. When we exercise, the brain becomes less sensitive to food, besides this, it also helps our brains grow and become better able to make wise decisions.

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You can see all these things at the Beijing Winter Olympics. Some technologies make the Games stand out and help people stay safe during COVID-19.

Driverless helpers

Walking inside Shougang Industrial Park, you can see different kinds of driverless cars. When you feel tired, you can get in a driverless minibus. When you feel hungry, you can buy food from a “driverless car store”. Some driverless cars can even send things to you just like a delivery man (快递员).

Body temperature check

People can wear a thermometer (体温计) on their skin. It looks like a bandage (创可贴). One charge (充电) can work for about ten days. Users can check their body temperature through an app on their smart phones. If someone gets a fever, the thermometer will report it.

Remote interview

Usually after each event, reporters will interview players face to face. To stay safe, the Beijing Winter Olympics will do remote interviews. The reporters can’t meet the players. But they can talk with each other by video.