Dieters have long sworn that grapefruit helps them lose weight. The Grapefruit Diet, also called the Hollywood Diet, dates back to the 1930s and has a host of celebrity fans including singer Kylie Minogue. It involves having grapefruit or grapefruit juice with every meal while cutting back on calories.
Now, scientists are beginning to believe them.
A study has found that drinking grapefruit juice when eating fatty food lowers the amount of weight put on by up to a fifth.
The research also suggested that grapefruit could be as good as prescription drugs at keeping blood sugar levels under control—a key part of managing diabetes.
The experiments were conducted on mice—but researchers say the results are true for humans. Professor Joseph Napoli, of the University of California, Berkeley, said, “We see all sorts of tricks about nutrition. But these results, based on controlled experiments, make it necessary to study the potential health-promoting properties of grapefruit juice further.”
The researchers found that when the mice were fed fatty food for three months, those given grapefruit juice to drink gained up to 18 percent less weight than those given water.
They also had lower blood sugar and insulin levels—despite eating the same number of calories and doing the same amount of exercise as the mice who drank water. In fact, grapefruit juice was as good at controlling insulin as the widely used diabetes drugs, the journal PLOS ONE reports.
However, the fruit juice only had an effect on weight when the animals ate fatty food. The researchers said they did not know how grapefruit stops the pounds from piling on.
Spokesman Mariette Abrahams, a dietician, said until then it is too early for people to try grapefruit diets. “Grapefruit should be part of a healthy balanced diet, but it shouldn’t be the focus of the diet.” she said.
1. What can be known about the Hollywood Diet?| A．It’s the origin of the Grapefruit Diet. |
| B．It was more popular in the 1930s than any time. |
| C．It may appeal to fat people. |
| D．Scientists may think it is nonsense. |
| A．They should have been conducted on humans. |
| B．The results apply to humans too. |
| C．Grapefruit could cure diabetes. |
| D．Mice prefer grapefruit juice to water. |
| A．The mice with high blood sugar. |
| B．The mice doing a lot of exercise. |
| C．The mice on a fatty diet. |
| D．The mice taking prescription drugs. |
| A．Nutrition of Grapefruit |
| B．Experiment on Grapefruit |
| C．Grapefruit Makes a Hit |
| D．Grapefruit Helps Keep Fit |
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【推荐1】Drinking more water is an excellent goal for your health. Water is also a calorie-free choice, so drinking more water can help you to lose weight or keep a healthy weight.
Always having water on hand makes it easier to remember to drink it. It’s important to drink more water any time you’ve been sweating, such as when you’re exercising or after spending time in a hot environment.
Drinking water before your meals and while you eat can help to reduce your appetite since thirst is often confused with hunger.
Tracking the amount of water you drink each day also works. This will help you to determine how much water you’re drinking and figure out if you might need to increase your intake. Remember to set a goal for how much water you want to drink each day.
| A．After meals, drinking water is a good choice. |
| B．The more water you drink, the healthier you are. |
| C．Here are some tips that can help you drink more water. |
| D．There’s no “right” amount of water for everyone to drink. |
| E．Replace your typical drink before and during meals with water. |
| F．Adding flavor to your water is a simple way to make it more tasty. |
| G．Always keep a water bottle into your bag or car and refill it regularly. |
【推荐2】The aging affects the human body in many ways. One of them is muscle loss (肌肉松弛) as we age. Scientists may not know exactly when muscles loss starts.
Equipment (设备) strength training
Equipment strength training is the best way to slowdown the process (过程) of muscle loss. Many gyms and health clubs have such muscle-building equipments as weights or running machines.
Also listen to your body. If an exercise causes pain, stop immediately. After the pain goes away you can try the exercise again, but with a lower weight or speed.
No equipment strength training
You do not have to use special exercise equipment or go to a gym to do strength training. You can just use your own body weight. Such excises include push-ups, side jumps, jumping jacks or deep knee bends.
Exercises that use body weight are usually safer for beginners. They can also be easier on the body, and you can do them anywhere.
Warm up
Give your muscles time to recover. Experts say it is better to rest one full day between exercising each specific muscle group.
| A．Have a break |
| B．The aging process can be stopped in many ways |
| C．They are great exercises to slow down muscle loss |
| D．Working with these equipments can be dangerous |
| E．Experts suggest warming up before strength training |
| F．You can slowly increase the weight as you get stronger |
| G．But what they do know is that it can be greatly slowed down |
【推荐3】Exercise can change how crucial portions of our brain communicate as we age, improving aspects of thinking and remembering, according to a new study of aging brains and workouts.
Experiments show exercise increases neurons of the brain essential for memory creation and storage, while also improving thinking skills. In older people, regular physical activity helps slow the usual loss of brain volume, which may help to prevent age-related memory loss and possibly lower the risk of dementia.
In a 2016 M. R. I. study, research about student runners suggested that running and fitness might have contributed to sharper minds. But little was known about whether and how exercise might change the communication systems of older brains.
So, for the new study, Mark Gluck, a professor in Newark, New Jersey, and his colleagues decided to see what happened inside the brains of older people if they began to work out. In particular, he wondered about their memory center. Unfortunately, its inner workings often begin to decline in thinking and memory. But Dr. Gluck suspected that exercise might change that.
Luckily, he and his colleagues previously had recruited older African-Americans from the area. The volunteers, most in their 60s, visited Dr. Gluck’s lab for physical checks. They agreed to have their brain activity scanned.
Some then started working out, while others chose to be a sedentary control group. All shared similar fitness and memory function at the start. The exercise group attended hour-long dance classes twice a week at a community center for 20 weeks. Then the scientists noticed subtle differences in how the exercisers’ brains operated, indicating a kind of youthful flexibility in the brain, in a way that the sedentary group’s brains couldn’t.
This study involved older African-Americans, though, a group that may not be representative of all aging people. Still, it seems that neural flexibility gained by exercising a few times a week “leads directly to memory flexibility,” Dr. Gluck says.
1. What remained unknown in the 2016 study?| A．How the function of our mind declined at old age. |
| B．Whether exercise could affect the brain of old people. |
| C．Whether regular workout could cure age-related diseases. |
| D．How young people sharpened their minds through exercise. |
| A．He had recruited some old people for regular check. |
| B．He always worked out with some local old patients. |
| C．He was well known in the area for his medical skills. |
| D．He got financial support from the state for his research. |
| A．They had frequently checked into hospital. | B．Their brains were as active as the other group. |
| C．They showed a youthful flexibility at thinking. | D．Their brains showed a normal aging tendency. |
| A．It is perfect without including other age groups. |
| B．Older African-Americans benefit most from exercise. |
| C．Sedentary people will suffer old-aged memory loss early. |
| D．Exercising a few times a week improves old-aged memory. |
【推荐1】Silkworms(蚕)were first brought from Asia to the ancient city of Byzantium around A. D. 550. It was two men who presented some silkworm eggs from China to Byzantine Emperor Justinian I in Constantinople, where he created a fruitful silk industry. Silkworms reached Italy through Sicily in the 12th century, and by the 13th century, silkworm farming had moved north to the Po River Valley. By the 16th century, silkworm farming had been introduced to the Como area.
Since silkworms require a constant, mild temperature, entire sections of farmhouses were turned over to them and whole families would often join in the work, adding fuel round the clock to fires to maintain the proper warmth. “Some even gave the worms the house and slept outside with the animals, ”says Ester Geraci, an official at Como’s Educational Silk Museum.
The process began with the 10-to 14-day incubation(孵化)of silkworm eggs. According to the museum, keeping the tiny, delicate eggs at just the right temperature was the task of the women. Once hatched, the worms, only about one millimeter long, had to be fed night and day. From a birth weight of only half a milligram, they would grow 10, 000-fold to a final weight of around five grams and a length of 8 to 9 centimeters in just 30 days. Then, in the final three days of their youth stage, the worms would start to make their cocoons (茧) out of one continuous thin silk-up to 1, 200 meters long-which they produced from near their mouths. After about a week, the cocoons were placed briefly in a hot, dry place to kill the adult insects inside. These cocoons were then put in hot water to facilitate the difficult and boring task of obtaining the silk. The minute end of the cocoon’s silk had to be located and placed onto a round object, which then unwound it from the water-warmed cocoon. The silk was then cleaned and made into fabric.
1. Which can best describe silkworm farming outside China?| A．It was a short-term investment. |
| B．It benefitted fruit growers. |
| C．It upset local emperors. |
| D．It was a success story. |
| A．Raising silkworms was a backbreaking job. |
| B．Silkworms like living in a cool environment. |
| C．Raising silkworms in farmhouses was common. |
| D．Silkworms living with other insects grow healthy. |
| A．They produce silk 3 days after being hatched. |
| B．They gain weight quickly in about a month. |
| C．They grow to 8 to 9 centimeters in two weeks. |
| D．They need one week to come out of their eggs. |
| A．To explain how silkworms reached Italy. |
| B．To encourage people to raise silkworms. |
| C．To introduce the farming of silkworms. |
| D．To show the life cycle of silkworms. |
【推荐2】Vitamin B could help lessen the effects of the most dangerous type of air pollution，according to a new study published recently. In the first study of its kind，a team of international researchers looked at the damage caused by one of the pollutants that has the most severe impact on health: PM2.5.
Particulate matter，or PM，is a type of air pollutant consisting of small particles of different sizes. PM2.5 has a diameter of fewer than 2.5 micrometers，about 30 times smaller than a human hair. These particles are so small that they can go into our respiratory system (呼吸系统), resulting in lung and systemic inflammation (炎症) and stress.
The team found that something as simple as a daily vitamin B supplement could potentially reduce the impact of the tiny particles on the human body，although they stressed that the research was in its early stages and the sample size was small.
For this study，10 volunteers were initially exposed to clean air and given a placebo (安慰剂) to check their responses. The group then took another placebo for four weeks before being exposed to heavily polluted air from downtown Toronto，where an estimated 1，000 cars pass every hour. The bad air was delivered to the volunteers through an “oxygen－type” face mask. The experiment was then repeated，with each volunteer taking a vitamin B supplement daily made up of 2.5 mg of folic acid，50 mg of vitamin B6，and 1 mg of vitamin B12. B6 can be found in liver，chicken and nuts，and B12 in fish，meat，eggs，milk and some cereals.
The researchers found that four weeks of vitamin B supplements reduced the damage of PM2.5 exposure by 28%－76%. The results highlight how prevention at an individual level could be used to fight the harmful effects of PM2.5.
1. Why is PM2.5 harmful to our health?| A．It pollutes and poisons the air. | B．It is too much to be got rid of. |
| C．It carries viruses and diseases. | D．It is easily breathed in and damages our body. |
| A．The process of the research was not scientific. |
| B．This kind of research has been done many times. |
| C．Further studies are needed to confirm their findings. |
| D．Vitamin B is hard to obtain in people’s daily life. |
| A．International researchers have a new finding. |
| B．Vitamin B could reduce the damage of PM2.5. |
| C．Particulate matter does great harm to our health. |
| D．Emission control and regulation are badly needed. |
| A．in a science journal | B．on a government website |
| C．in a fashion magazine | D．in a medical textbook |
【推荐3】The brain, like any other body part, gets old. However, not all brains age the same way. For example, women's brains may age more slowly than men's. That is the finding of a U.S. study from Washington University School of Medicine in St. Louis, Missouri.
Researchers there wanted to find out how the brain uses sugar. To do that, they studied just over 200 brains of men and women aged 20 to 80. They used PET scans to look at the flow of oxygen and sugar in the brains. The researchers found that the brains of women looked nearly four years younger than the brains of men who were bomb in the same year. Their findings suggest that the brains of men and women may use sugar differently as they age. But the researchers do not know why. Some scientists suggest that hormones（荷尔蒙）could play a part. And how the brain uses fuel, might help us understand some of the differences we see between men and women as they age.
On its website, the National Institute on Aging describes an aging brain. Parts of the brain get smaller, "especially those important to learning and other complex mental activities." Communication between neutrons（神经元）may decrease. Blood flow may lessen and inflammation（炎症）may increase. All these changes slow our recognitive abilities. We have trouble remembering things, finishing complex tasks or paying attention, just as Alzheimer's patients. It slowly destroys memory, thinking skills and, eventually, the ability to carry out the simplest tasks.
Considering what scientists already know about aging, the recent study about sex differences in the brain has raised some questions. For one, if women's brains age more slowly than men's, why do more women get Alzheimer's disease? Alzheimer's does not have a cure. However, doctors say that between 50 to 60 percent of Alzheimer's cases can be prevented by simple lifestyle changes. Whether you are a man or a woman, there are always some things you can do to keep your brain young and healthy.
1. What's the purpose of the research performed by the U.S. scientists?| A．To know why women live longer. |
| B．To figure out how the brain uses sugar. |
| C．To study the structure of the brain. |
| D．To find out the cause of Alzheimer's disease. |
| A．Women cat more sugar than men. |
| B．The flow of oxygen in their brains differs. |
| C．Women's brains use sugar differently. |
| D．The amount of sugar in women's brains is larger. |
| A．What happens as the brain ages. |
| B．Why a person suffers from Alzheimer's disease. |
| C．What makes Alzheimer' disease incurable. |
| D．How the changes improve the recognitive abilities. |
| A．Some other incurable diseases. | B．The ways to keep your brain young. |
| C．The research on Alzheimer's. | D．The other parts of the body. |
【推荐1】We all know that drinking too much is bad for us, but what about moderate (适度的) drinking?
We’ve known about the association between moderate drinking and good health for quite some time. Researchers have identified that people who drink a moderate amount are at a lower risk of things like heart disease and obesity than both people who drink a lot and people who never drink. It’s fairly well-established that,if you look at society at large,people who drink a moderate amount are the healthiest in a number of ways.
The problem is that moderate drinking isn’t an isolated (孤立的) behaviour .You can’t easily separate moderate drinking from the people who drink moderately, which means that you can’t easily identify whether it’s actually the alcohol that’s improving people’s health or something more complex.
The issue is pretty obvious when you look at the people who drink moderately in all of these studies.They tend to be wealthier,more educated,smoke less and in general are better off than both people who drink a lot and those who never drink. People who don’t drink alcohol are also different in a lot of ways, mostly bad — for example, illness, poverty, and previous alcoholism.
Recent studies in Israel and New Zealand show that there probably aren’t any significant health benefits to moderate drinking. Once you get rid of the effects of society, even a small amount of drink is associated with worse health.
It seems that moderate drinking probably isn’t good for our health after all. While there may be some minor heart health benefits, alcohol is addictive and causes damage to many other organs.
I’m going to keep drinking, but not for my health. Wine is delicious and beer is just wonderful. Drink for the taste,drink to socialise, but don’t drink because you think it’s going to cure your depression or heal your heart. But if possible, try to drink less.
1. What is the common belief about drinking alcohol?| A．Drinking has little to do with health. |
| B．Moderate drinking benefits our health. |
| C．Drinking reduces the risk of heart disease. |
| D．The healthier you are, the more you can drink. |
| A．A rich man. | B．A sick man. |
| C．A former alcoholic. | D．A poorly-educated man. |
| A．It’s an isolated behaviour. |
| B．It’s a good way to keep fit. |
| C．It’s more of a social activity. |
| D．It should be banned for health reasons. |
| A．Is Alcohol Suitable for You? | B．What Is Moderate Drinking? |
| C．Do You Know How to Drink? | D．Is Moderate Drinking Healthy? |
In England, people can also have summer in winter, or have winter in summer. So in winter they can swim sometimes, and in summer sometimes they should take warm clothes.
umbrella (伞)or a raincoat with them in the sunny morning, but you should not laugh at them.If you don't take an umbrella or a raincoat, you will regret (后悔) later in the day.
1. Why do people in England often talk about the weather?
| A．Because they may have several seasons in one day |
| B．Because they often have very good weather |
| C．Because the weather is warm just like in spring |
| D．Because the sky is sunny all day |
| A．sunshine and snow | B．black clouds |
| C．summer and winter | D．spring and autumn |
| A．their friends ask them to do so | B．it often rains in England |
| C．they are going to sell them | D．they are their favourite things |
| A．Bad Seasons | B．Summer or Winter |
| C．The Weather in England | D．Strange English People |
【推荐3】Many of us think of sharks as powerful, mysterious, and lonely as they move through the deep. And nowonder the fish have long been portrayed in popular media as lone predators, appearing out of nowhere to attack. But that image has come under inspection in recent years, as shark researchers around the world have discovered the fish gathering in large numbers and interacting with others of their own species in ways that are obviously friendly.
Yannis Papastamatiou, a marine scientist at Florida International University, and his team used acoustic transmitters to record the interactions over four years of about 40 reef sharks around Hawaii. Their study found that reef sharks return to the same communities year after year, forming clear preferences for sharks with some friendships that endured throughout the study. In his 2016 study, he found that individual sharks tagged with recording devices had thousands of interactions with their peers, with some pairs spending up to four straight days together. The study also found certain sharks were unmistakably companions. “These weren’t random associations,” he says.
Finding out why sharks socialize — and how much of their behavior is cooperative — is a challenge, but there are some clues, such as food availability and warmer waters. Great white sharks, are showing up in record numbers along southern California beaches as the population has doubled since 1994. While great white sharks typically maintain distances of about 30 feet from each other and don’t seem too close, they are clearly drawn together by a preference for the area. In some cases, there may not be an obvious purpose for shark’s friendship. At the Bimini Shark Lab, Smukall and his colleagues found that young lemon sharks sought out companionship of other sharks for no clear reason. There’s growing evidence that lemon sharks have their own personalities, which may influence whether they spend time with other sharks, he adds.
More would be known about the intimate lives of sharks if the field weren’t so new, due in part to a lack of funding and sharks’ negative reputation. “We’ve only had about 20 years to really start studying sharks,” says Smukall.
1. Why do the reef sharks return to the same groups every year?| A．To move to other places together. | B．To find a better place to lay eggs. |
| C．To change the food chain of the sea. | D．To search for the company of other fish. |
| A．Global Warming. | B．Preference for an area. |
| C．Sharks’ personalities. | D．Food availability. |
| A．Sharks usually spend four days with their peers. |
| B．The relationship between some sharks is steady. |
| C．All the sharks were attached to recording devices. |
| D．Sharks have thousands of interactions every day. |
| A．Sharks always have a bad reputation. |
| B．Scientist will begin studying sharks in 20 years. |
| C．There will be a long way to go before knowing sharks completely. |
| D．It is unnecessary to put money into the research of the sharks. |
【推荐1】A new pastor(牧师) named John reopened a church that had been abandoned in a suburb. He found it broken, and in need of a lot of repair work. His goal was to have everything done in time for his first service on Christmas Eve.
He worked hard. However, when John went to the church on Dec. 21, his heart sank: a large area of plaster (石膏) had fallen off the front wall due to a terrible storm the night before. John headed home, and on the way he stopped at a market selling items for charity.
One of the items was an exquisite( 精致的)handmade tablecloth. It was just the right size to cover up the hole in the front wall. He bought it and headed back to the church. It started to snow. An old woman had missed her bus, and he invited her to wait in the warm church for the next one. As John put up the tablecloth the woman asked him to check the corner for the initials(手写字母). They were her initials: she had made this tablecloth 35 years before. Then the war broke out, and forced her to part with her husband.
John wanted to give her the tablecloth. but she asked him to keep it for the church. John insisted on driving her home which he thought was the least he could do.
What a wonderful service he had on Christmas Eve! John noticed one old man staring at the tablecloth on the front wall. The man said it was similar to one that his wife had made many years before.
John brought the old man to the house where he had taken the woman three days earlier. He helped him climb the three flights of stairs to her apartment, and saw the greatest Christmas reunion he could ever have imagined.
1. According to Paragraph one, we learn that John decided to_______.| A．help people affected by a terrible storm |
| B．buy goods for charity in the neighborhood |
| C．repair the abandoned church before his first service |
| D．do some work for the local people |
| A．The woman’s husband had to leave her because of a war |
| B．Johns service on Christmas Eve was disappointing |
| C．Everyone was surprised by the beauty of the tablecloth. |
| D．John drove the old man home because he was lost. |
| A．he loved its colors | B．he had seen it in a church |
| C．It was like one his wife had made | D．it looked strange hanging on a wall |
| A．A kind pastor who had difficulty repairing an ancient church |
| B．A new pastor who gave his first service with a couples help |
| C．A tablecloth made 35 years ago being discovered by a pastor |
| D．An old couple being reunited on Christmas Eve through a tablecloth |
【推荐2】During summer holidays my mother and I used to escape to one of the lakes north of Prince Albert. In its magic surroundings we spent the long summer days in the open air, swimming and boating or just lying dreaming in the sun.
The last summer was particularly wonderful. For one thing, I was in love for the first time. My boy friend Don worked in Saskatoon, but the lake was his place-the beautiful wilderness attracted him deeply, so I thought it was not to see me that he got on his motorcycle as many Fridays as he possibly could, and drove three hundred miles along the rough roads to spend the week-ends at our place. Sometimes Don couldn't come, because he was hard up(生活拮据), and sometimes worked overtime.
One Friday night a storm broke out. I lay in bed and listened to the thunder and the rain beating on the roof. I tried not to expect Don. Yet I couldn't help imagining him fighting the storm. His motorbike, which had always looked to me so heavy, seemed fragile enough to be blown onto its side by the first strong wind.
I tried to close my throat against the tears. But when my mother, driven by the deep sympathy and understanding between us, came in to me. she kissed my cheek and found it wet.
“Don't get upset, Jane”, she said softly. “He may still come.”
It was hours later that I suddenly heard the sound of the roaring(轰鸣的) engine. The storm was dying. I lay still, relief and pain fighting for ascendancy(支配地位)within me as I heard Don's heavy tired footsteps on the wooden stairs.
1. Why was the last summer especially great for Jane?| A．She fell in love for the first time. | B．She had a lot of fun in the open air. |
| C．Her boyfriend bought a motorcycle. | D．Her boyfriend found a beautiful place. |
| A．He lived a poor life. | B．He didn't love Jane so much. |
| C．He worked in a remote village. | D．He didn't like traveling in bad weather. |
| A．She knew Jane was afraid of the thunder. | B．She knew Jane was worried about Don. |
| C．She heard Jane arguing with Don. | D．She heard Jane crying. |
| A．Excited | B．Anxious | C．Doubtful | D．Complicated (复杂的) |
【推荐3】So many things can keep you from seeing your loved ones in person, from busy schedules to long distances to a rather unexpected COVID-19 virus. Fortunately, thanks to modern technology, the people we miss are often only a phone call or text message away. But if you’re someone who prefers to type out messages. you may want io reconsider. A new study, published in the Journal of Experimental Psychology, found that communication that included voice, like a phone call or video chat, created stronger social relationships than communication through typing, like text messaging or email.
In the study, researchers used various experiments to measure relationships. In one, they asked 200 people what it would be like to reconnect with an old friend by email or by phone and then asked them to do one or the other. Although people anticipated that a phone call would be more awkward, hearing someone’s voice actually made the experience better.
“People reported they did form a stronger relationship with their old friend on the phone compared with email, and they did not feel more awkward,” said Amit Kumar, an assistant professor of marketing at the McCombs School of Business.
In another experiment, the researchers had strangers connected by either texting, talking over video chat, or talking using only audio. They found that both forms of voice communication — whether video or audio only — made the strangers feel significantly more connected than when they communicated by text.
Sabrina Romanoff, a Harvard psychologist, says people tend to text or email instead of calling because of convenience, as they see it as a controlled form of communication where they can “communicate information exactly in the way they want without unexpected additions by the other person.”
Romanoff says that in reality, texting can make it hard to determine the true meaning behind a conversation. “A phone call is actually more convenient when considering the pet effects of the message,” she explains. “Each party is more present, and therefore, able to understand the meaning behind the content without thinking about the endless possible meanings behind words.”
1. What does the passage mainly tell us?| A．Texting does harm lo social relationships. |
| B．Voice communication brings people closer. |
| C．A phone call does more good than a text message. |
| D．People prefer a text message rather than a phone call. |
| A．By comparing. | B．By reasoning. | C．By imagining. | D．By discussing. |
| A．Ensured. | B．Refused. | C．Expected. | D．Disagreed. |
| A．texting makes them feel more connected |
| B．they feel awkward when making a phone call |
| C．texting helps communicate their information exactly |
| D．calling helps determine the true meaning behind the conversation |
