2 . Taking between 9,000 and 10,000 steps per day appears to reduce the risk of an early death or heart-related event, adding reason to an idea that has been considered as unscientific.

The exact origin of the commonly held belief that people should aim for 10,000 steps a day is unclear, but it has been linked to a marketing plan promoting pedometers (计步器) in Japan. Now, a study by Matthew Ahmadi at the University of Sydney, Australia, and his colleagues suggests the figure could hold some truth.

The team studied more than 72,000 participants, with an average age of 61, in the UK Biobank study as they wore a movement-tracking accelerometer (加速度计) on their wrists for one week. “We were able to know their daily steps,” says Ahmadi. The participants were then tracked for an average of just under seven years.

During that time period, 1,633 people died and 6,190 heart-related events occurred. After adjusting other factors that could influence the risk of illness or death over that period—such as diet quality, smoking and doing other forms of exercise, the researchers found out that the best number of steps per day appears to be between 9,000-and 10,000, with the benefits then starting to tail off. Doing so was linked to a 39% lower risk of dying during the follow-up period and a 21% lower risk of a heart-related event. “It does appear to support the belief that the originally non-evidence based 10,000 steps target may indeed be about right,” says Dale Esliger at Loughborough University in the UK.

However, while the study was “extremely well designed” with “careful methods and statistical analysis”, Esliger says wrist-worn accelerometers aren’t always the best indicator of step count. The researchers also didn’t consider the number of steps taken per minute. “It’s possible that around 6,000 steps performed at a higher pace may be just as health protective as 10,000 slower steps,” says Esliger.

3 . What is sleep, and why do we need it?

When we sleep, we enter a specific state that lies somewhere between consciousness (清醒状态) and unconsciousness. During sleep, the body is at rest, but the brain remains highly ________ and hard at work. Sleep is vital for our survival, and a whole range of biological functions can be ________ only while we are in this state. Scientists are ________ to know more all the time, but the main functions of ________ seem to be: redirecting energy into clearing harmful things from the brain and body, building up learning and memory, ________ the immune (免疫的) system, balancing our emotional states, and repairing and restoring cells in the body. These ________ are essential for us to function properly, and when we sleep well, our mental and physical health are dramatically ________ .

Although many of the functions of sleep remain ________ , what is becoming increasingly clear is that sleep is ________ to our well-being and that in order to live well. we must take it as ________ as we take eating and exercise. The more science ________ , the more we understand that good sleep holds the keys to ________ and happiness.

________ its biological function, consistent good sleep, quite simply, feels great. By ________ sleep’s importance and how to improve it, it’s possible to ________ worrying about it, get into bed, and slowly fall asleep.

7 . For most, the first thing that likely comes to mind when thinking about vitamin C is either an image of orange fruits or its ability to keep your immune system healthy.     1    . Here are the primary benefits of vitamin C when applied topically to the skin.

It protects skin cells from environmental damage. Vitamin C’s main function in skin is that of a powerful antioxidant, protecting us from cell damage caused by free radicals (自由基). “    2    ,” Dr. Mack explains, and they are highly reactive. Vitamin C destroys these free radicals by donating electrons, preventing them from damaging skin.

    3    . Vitamin C is also one of the gold standards for evening skin tone and boosting radiance. “Vitamin C is a well-known skin brightener, preventing melanin production and eventually fading dark spots, resulting in a better skin tone,” Dr. Mack explains.

It firms skin and promotes collagen (胶原蛋白) production. Our skin is made of collagen and elastin, which are proteins that give it structure and flexibility.     4    . “Daily application of vitamin C helps to maintain the completeness of the collagen that we have, prevents rapid breakdown with age and promotes collagen production,” Dr. Mack says.

It works with other antioxidants for enhancing UV (紫外线) protection.     5    . A study in the Journal of Investigative Dermatology showed that the combination of vitamin C and E not only offered improved stability of vitamins C and E, but also improved skin’s UV protection.

How Your Nose Beats Bacteria

Scientists have discovered an incredible defence system in the human nose. Your nose is a powerful weapon     1     harmful bacteria entering your body. When you breathe in through your nose, you breathe in hundreds of different     2    (type) of bacteria, some of     3     can make you ill. Cells     4    (line) the inside of your nose produce a sticky mucus (黏液) that traps these tiny microbugs, and small hairs move the mucus out of your nose or to the back of your throat.

    5     scientists from Massachusetts Eye and Ear, a specialist teaching hospital in the US, have found is that your nose cells not only produce mucus, but also tiny sacs (囊) called exosomes. These exosomes are filled with antibacterial substances that kill bacteria directly. They     6    (release) in their billions at the first sign of     7    (infect). They also get a boost from the system that gets mucus     8    (move) out of your nose. The transport system of tiny hairs sweeps exosomes backwards, alerting the cells at the back of the nose to the incoming danger and arming them with antibacterial proteins     9    (fight) off the bugs.

Scientists had thought that the immune system only worked inside the body, but this shows that it protects you outside your body, too. “We have demonstrated in     10     live patient that the immune system reaches outside of the body, and actually goes and attacks pathogens (病原体) before they get into the body,” says Benjamin Bleier.

9 . Some Winter Activities

Winter activities are underestimated (低估). The days may be shorter, but the list of fun activities isn’t. Don’t let the winter blues take over.     1    

Finding your favourite.     2     Nobody likes cardio (有氧运动) for a long time, but signing up for an adult sports team, or taking a yoga class on the weekend can be a fun way to break up the boredom of going to the gym. Recreational (娱乐的) sports are also a great way to meet new people.

Walking on snow.     3     Walking with snowshoes is friendly to beginners, and suitable for kids and seniors alike. You can buy a set for under $100 or rent some for the afternoon. Take a friend or walk alone to enjoy the peacefulness of the outdoors in winter.

Skiing. Those that love it really love it. Hitting the ski hills is an old wintertime tradition. It gets you outside, boosts your mood, and serves as a core workout. You don’t need the latest gear (设备) to be able to have fun.     4     If you’re feeling tired of too much indoor time, get your heart pumping at a nearby ski hill.

    5     Taking an online class, or picking up an instrument for the first time, can be incredibly rewarding. Expanding your professional skill can do wonders for your future job prospects. It may take a little planning, but consider learning something new this season.

10 . Living a healthy life is all about choosing to make healthy choices each day. We’ve put together some good tips for starting a healthy life.

Create specific health goals

When you have specific goals you want to achieve, you’ll be more encouraged to make changes in your life.     1    . And then you can set smart goals that are specific and measurable to better achieve your success.

    2    

It’s no secret that eating health y food is one of the keys to achieving a healthy life. When you follow a healthy diet, you reduce the risk for heart disease, high blood pressure, and other diseases. More than that, healthy eating can relax you and make you happy.

Drink plenty of water

Just like tasty food, water is necessary to keep your body healthy. Water helps you digest(消化)food, keeps you hydrated(补水), and protects your body.     3    . This amount can change depending on your age, weight, and physical activity level.

Exercise regularly

Find a type of physical activity that’s enjoyable for you.     4    . Being active helps you lose weight, improves your cognitive function(认知能力), and lifts your spirits. Experts suggest that adults get at least 150 minutes of exercise each week.

Get enough sleep

A good night’s sleep can help you avoid getting sick, keep a healthy weight, and start a good day. Most adults need at least 7 hours of quality sleep each night.     5    .