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    Jamie Whitmore, 43, isn't used to slowing down. The professional athlete who became a gold medalist of Olympics for the disabled has never met a challenge she couldn't overcome, whether it was a mountain bike race-or cancer.

    One morning in 2007, Whitmore found her leg muscles were tight when trying for a jog. Thinking she'd pushed herself too hard in the last race, she ignored the pain. Later at a sports camp in Arizona, she realized something was wrong. "Once I got on my bike I was so painful that it was hard to pick my legs up. I flew back home to go to a hospital." What doctors found shocked them all: Whitmore had a soft tissue tumor (肿瘤)that started in the bone, and the tumor was wrapped around her nerve of waist, touching several vital organs.

    After the surgery, Whitmore had to learn to walk again with the help of a physical doctor. She also started radiation treatment, but four months later, doctors had worse news: A scan had shown the cancer was back. "This time it was more aggressive. Doctors took the rest of my nerve in the waist, and removed some cancer from my tail bone. " Whitmore developed sepsis(败血症) from the surgery and endured a two-month recovery. "My scans were coming back clear of cancer, but now I had all of these other complications(并发症)."

    Today, Whitmore is a mother and cancer-free. She has won a gold medal in the Paralympics, and has set two world records. Whitmore has some advice for others with limitations: Never let anyone tell you what you can and cannot do. You have to find out yourself. Some doctors told me I would never ride anything more than a stationary bike. And yet I rode my mountain bike 104 miles climbing from 9,000 feet to 14,000 feet. You just can't give up."

    The best movies for teenagers are listed here. You can pick one for your teen to watch it with you or their best friends.

    ⒈Eighth Grade

    Kayla is a shy, socially anxious girl trying to get by the last few weeks of middle school. She earns the "most quiet" girl title in school, but at home, she posts online self-help and motivational videos that not many people watch. Kayla is raised by her single father Mark, who tries to disconnect Kayla from the social media.

    ⒉Dead Poets Society

    Mr. Keating, an English teacher, introduces his students, all set to become doctors and lawyers, to poetry and free-thinking. Each of his students deals with several issues. He encourages them to form the Dead Poets Society where they read and write poetry.

    ⒊The Hunger Games

    Based on a book by Suzanne Collins, the story is set in a country called Panem, which was once the ruins of North America. Every year, young boys and girls from the 12 districts of Panem fight in the Hunger Games, a televised competition in which the contestants (参赛者) compete against death.

    ⒋The Break fast Club

    It begins with five students at the Shermer High School, Claire, a princess, John a criminal, Andrew, an athlete, Brian, a bookworm and Allison, an unfortunate person, who are forced to spend 9 hours together on a Saturday. In spite of their differences, they find that their social problems are more similar than they think. The film tries to encourage breaking social boundaries for positive self-identification in the world.

    Have you ever thought, if all ice in Antarctica(南极洲) and the arctic(北极) melts due to the global warming, what will happen? But one thing is sure with 100% certainty, penguins in Antarctic and the arctic will be in big trouble.

    Rising temperatures in coming years would lead to less sea ice in the Southern Ocean that surrounds Antarctica and fewer habitats and feeding grounds for penguins, says the World Wildlife Fund (WWF) in its report 2 Degrees is Too Much.

    Antarctica and the Arctic are the most threatened regions from climate change. In the Antarctica, the temperature has risen 2.5 degrees in the past 50 years. This speed is nearly five times faster than that before the Industrial Revolution. It is mainly caused by burning fossil fuels. Unless nations reduce carbon dioxide emission, the world will warm by an average of 2 degrees in less than 40 years. Rich nations should agree to reduce greenhouse gas emission. Temperatures near the Poles have risen much faster, which has led glaciers on the Antarctic Peninsula to melt quickly.

    The situation is quite critical, because in the past 50 years the number of emperor penguins(帝企鹅) has decreased by 50 percent across the whole Antarctica. On the northwest coast of the Antarctic Peninsula, the number of Adelie penguins(阿德利企鹅) has dropped surprisingly over the past 25 years.

    Fifty percent of the habitats of the emperor penguin and 75 percent of the habitats of the Adelie penguin face a rapid reduction, or even disappearance, if the global temperature rises 2 degrees above pre-industrial levels.

    With a 2-degree increase in global temperature and the decrease in sea ice thickness, emperor penguins will find it difficult to find new areas to live. With less sea ice, penguins could be pushed further south, but this could prevent them from hunting for food during the dark winters, because they need at least a few hours of daylight to find their food.

    There are various ways in which to read body language so that you can understand how someone is feeling. Reading emotional clues （线索）is one of them.

    Crying is considered to be caused by an explosion of emotion in most cultures. Often times crying is considered a sign of sadness, but crying can also be an expression of happiness. Crying can also come about through laughter and humor. Thus, when judging crying, you'll need to look for other signs to determine the meaning of the crying. Crying can also be forced in order to gain sympathy or to cheat others. This practice is known as " crocodile tears" , an expression that draws on the wrong idea that crocodiles" cry" when catching prey（猎物）.

    Signs of threat include v-shaped eye brows wide eyes, and an open or down-turned mouth. In a similar way, arm tightly crossed over the other is a common sign that the person is angry and is closing himself off to you.

    When people show anxiety, they display increased facial movements, and their mouth made into a thin line. Individuals who are anxious may also play with their hands, unable keep them in one spot. Anxiety can also or have nervous legs. It can be conveyed when people seemingly unconsciously（无意识 地）tap their feet or have nervous legs.

    Embarrassment can be expressed by turning the eyes or shifting them away. If someone looks down at the floor a lot, they are probably shy, afraid, or embarrassed. People also tend to look down when they are upset, or trying to hide something emotional. People are often thinking and feeling unpleasant emotions when they are in the process of staring at the ground.

    There are also some signs of pride. People show pride by displaying a small smile, holding their head backward, and putting their hands on their hips.

    Many people don't have a home because of an illness or because they lost their jobs. They have bad health and can't start working, and because of that, they can't pay for a doctor, so it's a never-ending circle. Homeless people don't have anywhere to go, so they have to sleep on the streets, covering themselves with newspapers and looking through the rubbish cans to find some food or warmer clothes.

    Seeing these horrible living conditions, the Australian charity Beddown decided to help these people in need. They came up with an amazing idea to make shelters in places that are vacant at night-like parking lots! The organization asked one of the largest car park-opera tors, Secure Parking, and they agreed upon it.

    “It was great to start with a group of our volunteers to help us and set up some beds. Although as expected we had a few challenges to overcome, it was good to start bringing Bed down to life. Beddown will provide an immediate response for those who can not sleep well to access safe, find shelter-and access to a real bed and a great night's sleep. We will work with our other partners to provide long-term solutions to providing our guests with accommoda-tion, education and employment opportunities.” The founders of Beddown said in one of their Instagram posts.

    The charity also provided other services to the guests, like doctors, nurses, dentists, hairdressers. They gave them new clothing, a place to clean themselves and helped provide social services. “After spending the week here, having a good sleep at night, it reminded me of life and I want to begin my life again,” one homeless man said.

    Cities usually have a good reason for being where they are, like a nearby port or river. People settle in these places because they are easy to get to and naturally suited to communications and trade. New York City, for example, is near a large harbour at the mouth of the Hudson River. Over 300 years its population grew gradually from 800 people to 8 million. But not all cities develop slowly over a long period of time. Boom towns grow from nothing almost overnight. In 1896, Dawson, Canada, was unmapped wilderness (荒野) . But gold was discovered there in 1897, and two years later, it was one of the largest cities in the West, with a population of 30,000.

    Dawson did not have any of the natural conveniences of cities like London or Paris. People went there for gold. They travelled over snow-covered mountains and sailed hundreds of miles up icy rivers. The path to Dawson was covered with thirty feet of wet snow that could fall without warning. An avalanche (雪崩) once closed the path, killing 63 people. For many who made it to Dawson, however, the rewards were worth the difficult trip. Of the first 20,000 people who dug for gold, 4,000 got rich. About 100 of these stayed rich men for the rest of their lives.

    But no matter how rich they were, Dawson was never comfortable. Necessities like food and wood were very expensive. But soon, the gold that Dawson depended on had all been found. The city was crowded with disappointed people with no interest in settling down, and when they heard there were new gold discoveries in Alaska, they left Dawson City as quickly as they had come. Today, people still come and go—to see where the Canadian gold rush happened. Tourism is now the chief industry of Dawson City—its present population is 762.

This weekly four­day physical activity schedule will get your kids excited about being active.

Tuesday

When the kids get home from school, don't let them go straight to the TV and get settled in. Encourage them to get moving and get off the sofa by giving them a pedometer(计步器). Pedometers are the most fun when parents also use one because that turns stepping, walking and running into a game to see who can get the most steps.

Thursday

The kids have done a great job so far this week, but now they long for a little more TV time. Instead of turning on cartoons, let them watch fitness movies made just for kids. These movies encourage watchers to get up and dance along to kid­friendly music.

Saturday

Get the whole family out of the house together and over to a park. Bring lots of sports equipment, pack a healthy picnic and have a family competitive sports day. Kids and adults get into groups and play against each other in tennis, basketball or soccer. After everyone has played hard for a couple of hours, stop for a picnic and then if your family isn't too tired, go back and play some more.

Sunday

Every child loves to play video games and there is no better time to allow kids to play them than on Sunday when no homework is due. But don't let them play a game that forces them to sit down for hours. Dance games with a floor mat(垫子) to help kids follow the dance moves are popular to kids.

My father died when I was nine, and I remember doing the household chores to help my mother. I hated changing the vacuum cleaner (真空吸尘器) bag and picking up things the machine did not suck up.

Twenty years later, in 1978, I was doing chores at home alongside my wife. One day the vacuum cleaner was screaming away, and I had to empty the bag because I could not find a replacement for it. With this lifelong hatred of the way the machine worked, I decided to make a bagless vacuum cleaner.

Easier said than done, of course. I didn't realize that I would spend the next five years perfecting my design, a process that resulted in 5,127 different prototypes (设计原型). By the time I made my 15th prototype, my third child was born. By 2,627, my wife and I were really counting our pennies. By 3,727, my wife was giving art lessons for some extra cash, and we were getting further and further into debt. These were tough times, but each failure brought me closer to solving the problem.

I just had a passion for the vacuum cleaner as a product, but I never thought of going into a business with it. In the early 1980s, I started trying to get licensing agreements (许可协议) for my technology. The reality was very different, however. The major vacuum makers had built a business model based on the profits from bags and filters (滤网). No one would license my idea, not because it was a bad one, but because it was bad for business.

That gave me the courage to keep going, but soon after, the companies that I had talked with started making machines like mine. I had to fight legal battles on both sides of the Atlantic to protect the patents on my vacuum cleaner. However, I was still in financial difficulties until 1993, when my bank manager personally persuaded Lloyds Bank to lend me $1 million. Then I was able to go into production. Within two years, the Dyson vacuum cleaner became a best-seller in Britain.

Today, I still embrace risk and the potential for failure as part of the process. Nothing beats the excitement of invention. Go out and brainstorm your ideas. You are not bound to any rules — in fact, the stranger and riskier your idea, the better.

Physical activity is important in preventing cardiovascular(心血管的) disease in young people so long as they don't undertake very intense activity on days when air pollution levels are high, according to a recently released study.

Until now, little has been known about the relationships between the health benefits of physical activity taking place outdoors and the potentially harmful effects of air pollution. Previous research by the authors of the current study had investigated the question in middle-aged people at a single point in time, but this is the first time that it has been investigated in young adults aged between 20—30 years over a period of several years. In addition, the researchers wanted to see what happens when people increase or decrease their physical activity over time.

At each health check-up, the participants completed a questionnaire asking about their physical activity in the past seven days and this information was changed into units of metabolic equivalent task(MET, 代谢当量任务) minutes per week(MET-mins/week). The participants were divided into four groups: 0, 1—499, 500—999 and 1000 or more MET-mins/week. People are recommended to do 500—999 MET-mins/week and this can be achieved by; for example, running, cycling or hiking for 15—30 minutes five times a week, or brisk walking, doubles tennis or slow cycling for 30—60 minutes five times a week.

The researchers used data to calculate annual average levels of air pollution, in particular the levels of small particulate matter that are less than or equal to 10 or 2. 5 microns in diameter, known a PM10 and PM25.

Overall, the results show that physical activity is associated with a lower risk of developing cardiovascular disease among young adults. However, when air pollution levels are high, exercising beyond the recommended amount may offset or even reverse the beneficial effects. The study cannot show that air pollution causes the increased cardiovascular risk, only that it is associated with it.

Check out some fun weekend activities from our friends at Arizona Parenting.

Walk in the Wild: Walk or run for wildlife at the Phoenix Zoo's Walk in the Wild 2016. Put on your favorite animal dress and take part in the one mile or 5K, enjoying the sights and sounds of the Zoo. Walk in the Wild includes a morning full of unique activities you won't find at any other valley walk, including all day zoo admission and a lakeside after party.

Register online. 6-10 am. Phoenix Zoo, 455 North Galvin Parkway, Phoenix. 602-286-3800.

Free Museum Day: It is hosted by Sesame Street and HBO at the Children's Museum of Phoenix.  Kids can participate in activities, enjoy a performance by the Sesame Street Muppets and get to join the Everyday Heroes Club. An act of kindness is all it takes to become a member. Performances and activities will take place at 10:30-11:30 am and 1:30-2:30 pm.

9 am－4 pm. Children's Museum of Phoenix, 215 N. 7th Street, Phoenix. 602－253－0501.

Sunday A'Fair: Sunday A'Fair features free outdoor concerts in Scottsdale Civic Center Park by top Arizona musicians, along with an artsandcrafts market, fun activities for children and families, guided tours of the sculptures in the park and free admission to Scottsdale Museum of Contemporary Art (SMoCA). Guests are invited to bring blankets, lawn chairs or picnic baskets, and enjoy a relaxing afternoon of great entertainment. Delicious foods, snacks, beer, wine and soft drinks are also available for purchase.

12-4 pm. Scottsdale Center for the Performing Arts, 7380 E. 2nd St. , Scottsdale. 480-994-ARTS

Take a view, the Landscape（风景）Photographer of the Year Award, was the idea of Charlie Waite, one of today's most respected landscape photographers.Each year, the high standard of entries has shown that the Awards are the perfect platform to showcase the very best photography of the British landscape.Take a view is a desirable annual competition for photographers from all comers of the UK and beyond.

Forty-nine years ago, on April 22, 1970, twenty million Americans took to the streets to voice their concern about the deteriorating environment. The movement led to Earth Day.

Unfortunately, our planet is in worse shape now than it was when Earth Day was first celebrated. The good news is that it's still not too late to reverse (转变) climate change if we all do our part. This Earth Day, take the first step towards helping our planet by participating in one of these fun activities.

NASA is putting our planet up for adoption so you and your friend can apply for a portion (份额) of the planet as your own. The space agency has divided the globe into 64,000 sections, each about 55 miles wide. All you have to do is type your name into NASA's "Adopt the Planet" site and you will be offered the location of your "slice of paradise (天堂) "complete with details of its environment and climate. NASA hopes that this activity will inspire interest and care about our planet.

Search giant Google is also trying to engage the public with an updated Google Earth focused on Earth Day events. Through a new Voyager feature, users will be able to discover stories from around the world, learn about new places by reading "Knowledge Cards" and send postcards.

If you happen to be anywhere near the nation's capital on April 22, join the millions that are expected to participate in the Earth Day March at the National Mail. The mission of the event that will feature guest speakers and musical performances is to mobilize (动员) citizens into taking action by promoting this year's Earth Day theme; climate and environmental science literacy.

While participating in the above-mentioned activities is a great idea, it is just the beginning. All that is required are small lifestyle changes. Planting a tree or two, going meatless just one day a week, or switching your plastic water bottle for a reusable one will go a long way to help reverse the damage we have caused.

"I have slept on the Embankment (路堤), " wrote George Orwell in 1933, adding that, despite the noise and the wet and the cold, it was "much better than not sleeping at all". Nine decades on and Charing Cross and the Embankment are once again full of rough sleepers, even during the coldest days of December. It is a pattern found in much of the rich world.

However, it does not have to be this way. In post-war America, there was little rough sleeping, and homelessness was falling so fast that sociologists predicted it would soon disappear. Even today, some rich, successful cities, including Tokyo and Munich, have few people living on the streets.

These places offer lessons on how to reduce homelessness. One is that tough love can sometimes work. Conservatives argue that softer policing policies in the 1970s, including careless attitudes to public drunkenness, were in part responsible for the rise in homelessness. The world could learn something from Greece, where strong family networks ensure that those down on their luck find someone to take them in. Many experts argue that it is counterproductive (事与愿违的) to give money to someone begging on the street. Better, they say, to donate to a charity.

Yet, most people believe tougher policies will ultimately do little if housing costs remain high. This is the underlying reason for rising homelessness. So, the state can do something to help. For example, more generous rent allowance might actually save governments money in the medium term—after all, demands on health-care services and the police would decline. Another option is for the state to build more housing itself. In Singapore, a place where there is practically no homelessness, 80% of residents live in government-built flats which they buy at knock-down prices.

The most effective reform, however, would be to make building more homes easier. The problem of rough sleeping in Germany and Switzerland, two countries with minimal real-house-price growth in recent decades, is less acute. Japan has used its fair share of strong-arm policies to deal with the homeless, but then it introduced a big urban reform in the early 2000s.

Did you know that Albert Einstein could not speak until he was four years old, and could not read until he was seven? His parents and teachers worried about his mental ability.

Beethoven's music teacher said about him, "As a composer (作曲家) he is hopeless." What if this young boy had believed it?

When Thomas Edison was a young boy, his teachers said he was so stupid that he could never learn anything. He once said, "I remember I used to never be able to get along at school. I was always at the foot of my class …My father thought I was stupid, and I almost decided that I was a stupid person." What if young Thomas had believed what they said about him?

When the sculptor Auguste Rodin was young, he had difficulty learning to read and write. Today, we may say he had a learning disability. His father said of him, "I have an idiot (白痴) for a son." His uncle agreed. " He's uneducable ， " he said. What if Rodin had doubted his ability?

Walt Disney was once fired by a newspaper editor because he was thought to have no "good ideas". Enrico Caruso was told by one music teacher, "You can't sing. You have no voice at all." And an editor told Louisa May Alcott that she was unable to write anything that would have popular attention.

What if these people had listened and become discouraged? Where would our world be without the music of Beethoven, the art of Rodin or the ideas of Albert Einstein and Walt Disney? As Oscar Levant once said, "It's not what you are but what you don't become that hurts."

You have great potential (潜能). When you believe in all you can be, rather than all you cannot become, you will find your place on earth.

Drug development is a risky and costly business. Many possibly effective drugs fail to cut the mustard during the experiments. One reason is that drugs which work on lab animals may not work quite so well in human tests. Being able to pick winners and losers as early as possible would save money, and the One Health Company thinks it may have found a way. It is offering to help medical groups test their cancer drugs on sick pets. 

There are several benefits. By treating animals with existing cancers, it hopes to avoid a problem with modern animal research, which is that the "model" animals and diseases that are used to test drugs are not always good stand-ins (替身) for the natural illness. For example, mice used to test cancer drugs may have had their tumours (肿瘤) placed into their bodies, or their immune systems weakened with drugs.

Another plus is that pet owners tend to be great caretakers who are very knowledgeable about their four-legged friends and are likely to report even small changes in behaviors. Lab animals are checked far less often. 

Perhaps the most useful aspect of using pets for drug experiments, however, is that there is no law on animals' medical records. One Health has been able to get 98% of records on animals from hospitals—a number that is impossible for humans. That allows the company to find the right animals for a drug experiment.

Based on the benefits above, the company hopes that pets will prove useful in other diseases in addition to cancers. Horses, for example, seem to be good stand-ins for humans when it comes to arthritis (关节炎). Cats, meanwhile, may prove instructive in breast cancer research.

Forgiveness is important in children and adults for restoring relationships and limiting future conflicts. A recent study suggests that teaching children to understand other people's perspectives could make it easier for them to learn how to forgive other people. The study also found that teaching children to make sincere apologies can help them receive forgiveness from others.

Mulvey, an associate professor of psychology at North Carolina State University, led the study. Her team enlisted 185 children, aged between 5 and 14 , in the study. Researchers conducted in an interview with each child that collected background information and assessed the child's "theory of mind" skills. Theory of mind is your ability to understand that someone else's beliefs, intentions and desires are different from your own.

Researchers then led each child through a series of scenarios (设想情况) involving other children who are "in group" and "out group." Specifically, each participant was told they were part of a group, such as the green team. During interviews, researchers described some children as also being on the green team (making them in-group), while other children were on the yellow team (making them out-group). In each scenario, interviewers asked study participants whether they were willing to forgive a group that left them out of a game or activity.

There were three main findings. First, children are more likely to forgive someone if he / she has apologized. Second, children are more likely to forgive people who are "in group." Third, the more advanced a child's theory of mind skills are, the more likely they are to forgive others.

The researchers identified two things that parents and teachers may want to focus on related to forgiveness. One is helping kids understand how important it is to apologize in a meaningful way. The second focus area is helping kids understand the perspectives of other people, even if they are different from you.

Mulvey says, "One of the biggest implications of our study is that teachers and parents need to actively help children cultivate theory of mind skills, which will aid them in navigating a diverse and complex world in the future."

Twenty-three states require high schoolers to take the subject, and more could join them in an effort to boost the next generation's financial literacy(理财素养). The number of states requiring high schoolers to learn about personal money matters continued to tick higher in 2021, and another state—Florida—is ready to join the group shortly. In Florida, a law has been passed to require students to take a course in personal finance before graduating.

"Financial concerns have been heightened by the Covid-19 pandemic(大流行病), and rising inflation(通货膨胀) is tightening household budgets. Those factors, combined with continual worries about burdensome student debt levels and shaky retirement security, have created a stronger case for making personal money skills a priority for high schoolers, who are soon to make decisions about college loans or finding a job," an advocate for financial literacy said.

Financial literacy—a knowledge of concepts like saving, credit, interest rates, investing and risk assessment—is generally low among American young adults, according to a recent report from the Teachers Insurance and Annuity Association of America Institute. Two-thirds of Generation Z, members born between 1997 and 2012, for example, couldn't correctly answer more than half the financial questions in the survey, which compared financial literacy across five generations.

"The pandemic has shown a critical need for the average American to have these skills," said Tim Ranzetta, co-founder of Next Gen Personal Finance. "State-level surveys conducted for Next Gen have found strong support for high school personal finance requirements," Mr. Ranzetta said, "and dozens of proposals have been presented to the law-making bodies in the government. It's uncertain how many will become law, but a requirement in a large state like Florida is likely to propel other states' efforts." He also said," There will be a FOMO(Fear of Missing Out) effect."

Life can bring us down from time to time. At some point, you may find yourself in what you will consider as your darkest hour. As you try to find your way out of that bad situation, you should try to remind yourself that there will always be a reason to be grateful.

If you look at your situation now and compare it with someone else who is in much deeper trouble than you, I am sure that you'll find something to be thankful for. We all have our share of problems, but complaining about them so much only makes us blind to the fact that there are the miracles (奇迹) which happen around us each day.

When all your needs are provided, then you should be content and happy. If you have a roof over your head, some proper clothes to wear, enough food on the table, a comfortable place to sleeping, clean water to drink and you are free to make your own choices, then you should be happy and grateful. Many people all around the world especially those who are at war or those in very poor countries, would give anything to be in your shoes.

Even if you lose all your money or possessions and your heart is broken for some reason, as long as you are still alive, then everything you have lost can be regained. If you have a few good friends who will be there to support or help you, then you will be glad because true friends are hard to find. As long as you have someone to love and someone to love you back, then you are a very fortunate person. Remember to be patient and trust that things will get better.

Visitors to Rome can now see one of the most important private collections of ancient Greek and Roman marble sculptures. The 90 works from the Torlonia Collection opened this week in the newly rebuilt Palazzo Caffarelli, overlooking the Roman Forum. Among the works is a marble fountain that was made in ancient Greece. Experts on ancient Rome believe the fountain once stood in the garden of the general and statesman Julius Caesar. At the time, it was already hundreds of years old.

The 620-piece Torlonia collection is believed to be the greatest private collection of classical art in the world. It was started more than a century ago by Prince Alessandro Torlonia. He found many of the pieces on the grounds of his family's Roman properties. Wealthy from a business relationship with the Vatican, the family purchased other well-known sculpture collections. In 1884, the Prince built his own museum to show off his collection. When the museum closed in 1976, the pieces went into storage.

"The reappearance of such a collection is a very important event, said art historian Salvatore Settis. "When I saw them for the first time, it was very emotional, because I knew most of those pieces from books, but I had never seen them." The Torlonia family chose Settis to help with the difficult job of deciding which works should be shown to the public.

Do you love food? Whether you're a foodie or someone who just likes eating, there is so much to choose from. We know that too much of the wrong kind of food can be bad for our health, but for some people having a food allergy means eating certain things can actually be harmful — and now, it seems, this is affecting more and more of us.

An allergy is caused by the immune system fighting substances in the environment, known as allergens(过敏原), which should be seen as harmless. Food allergies can cause life-threatening reactions, which means people have to spend their lives following strict dietary restrictions and worrying about the ingredients of everything they consume. Allergy specialist Dr Adam Fox says, "If you look back over, say, 30 or 40 years… there are much more allergic problems around now than there were."

We often hear about people having allergies to dairy products and to peanuts. Last year a young girl died after suffering a deadly allergic reaction from eating a baguette containing sesame seeds. This led to a call for better food-labelling laws.

Research has found that this problem is particularly affecting children. More and more of them are having allergic reactions to certain foodstuffs. Dr Alexandra Santos from King's College London says "food allergy now affects about 7 percent of children in the UK and 9 percent of those in Australia. Across Europe, 2 percent of adults have food allergies".

So what might be the cause? Dr Santos says the increase in allergies is not simply the effect of society becoming more aware of them and better at diagnosing them; it seems to be more environmental. She says possible factors are "pollution, dietary changes and less exposure to microbes (微生物), which change how our immune systems respond".

A lot of work is being done to try and find a cure, but that's not easy. So for now allergy sufferers must watch what they eat and they must rely on clear and accurate labelling.