While many people aren't getting enough calcium, new research cautions that some people may have the opposite problem: They could be getting too much. Americans spend more than $1 billion a year on calcium supplements in hopes of delaying osteoporosis the brittle bone disease that cripples many elderly women and some men. Yet recent studies link calcium supplements to a higher risk of heart attacks. Last month, the U.S. Preventive Services Task Force issued a draft recommendation against taking calcium and vitamin D, saying there wasn't enough evidence of benefit to justify the risk.
For generations of Americans who grew up encouraged to drink milk to maintain strong bones, the reports raised troubling questions: Is calcium not so important after all?! Are the supplements unsafe? And how much is too much? “It's gotten very confusing but it doesn't need to be,” says Ethel Siris, director of the Toni Stabile Osteoporosis Center in New York. How much calcium people need varies by age and gender.“Adults generally need 1,000 mg daily, rising to 1,200 mg for women over 50 and men over 70, according to guidelines issued in 2010. Children need 1,300 mg daily during the peak growing years of 9 to 18.”
People also need sufficient levels of vitamin D to absorb the calcium. The IOM recommends 600 interactional units a day for most adults, and 800 daily after age 70, although many physicians recommend more. It is difficult to take in that much vitamin D from food sources, so experts say many people should take vitamin D in supplement form.
Getting adequate calcium from food is easier. For example, 8 ounces of milk or 6 ounces of yogurt has 300 mg of calcium, and one cup of spinach has 270 mg.
But studies linking calcium supplements to heart attack have made experts more cautious of excess calcium than before. A study of 24,000 Germans published in the journal Heart last month, found that those who got their calcium exclusively from supplements were more than twice as likely to have a heart attack as those who took no supplements.
Exactly how calcium supplements might contribute to heart attacks baffles cardiologists. “Nobody has associated the calcium in your bloodstream with calcification in your arteries," says Nieca Goldberg, medical director of the Joan H. Tisch Center. Still, she says she now urges patients get their recommended calcium from food than from supplements to avoid possible problems.
Osteoporosis experts also urge patients not to take more than the recommended amount of calcium. “People should definitely stop taking two big calcium supplements a day,” says Dr. Dawson-Hughes. Even if the risks remain unclear, taking more than the body can absorb doesn't benefit bones, “so it's not worth any risk.” She adds.
1. According to the new studies, taking much calcium might ________.| A．delay aging | B．build muscles |
| C．cause heart problems | D．cure bone diseases |
| A．Taking calcium supplements is unsafe. |
| B．Adults need more calcium than children. |
| C．Age and gender determine how much calcium is needed. |
| D．It is safer to take calcium from food than from supplements. |
| A．Interest | B．Amaze |
| C．Frighten | D．Puzzle |
| A．Taking two calcium supplements a day is good for health. |
| B．It might be wiser to take recommended calcium from food. |
| C．It is easy for people to obtain enough Vitamin D from food. |
| D．The benefits of taking calcium supplements outweigh its risks. |
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【推荐1】Light-to-moderate alcohol consumption may offer some protective benefits for patients with heart disease, a new study suggests. The research pulled data from a combined sample field of 48,423 patients, thousands of whom had history of heart-related diseases.
The researchers noted that lifestyle and dietary habits play a major role in secondary prevention of cardiovascular disease (CVD), but that the impact of alcohol consumption on patients’ prognosis remains unclear. “While light-to-moderate alcohol consumption is associated with a lower risk of developing multiple cardiovascular outcomes in general population groups, it’s difficult to extend the supposed cardio-protective effects to CVD patients because of their typically older age and compromised vasculature as well as the medications they take to prevent secondary events,” researchers wrote.
Among the patient sample, former drinkers were separated from current drinkers, with the latter being broken into three groups of low-level drinkers, medium-level drinkers and high-level drinkers. Patients were followed until either their death or first detected heart-related diseases.
An analysis of three major cohorts together with those from 12 published studies found J-curve relationships between alcohol consumption and mortality in those with cardiovascular disease. The greatest reduction in all-cause mortality was found among patients with light alcohol consumption. “In summary, our study shows an alcohol intake up to about 105g a week is associated with lower risks of both mortality and subsequent cardiovascular events among CVD patients,” the team wrote.
The research team warned that the study had limitations and that current drinkers may not need to stop drinking for secondary prevention of cardiovascular disease, but rather be informed that lower levels of consumption may be associated with reduced risks. Patients who are non-drinkers, however, should not be encouraged to take up light drinking.
1. Why does the author mention the figure in paragraph 1?| A．To emphasize the number of patients. | B．To show the reliability of the research. |
| C．To stress the importance of the sample. | D．To prove the risk of alcohol consumption. |
| A．They published twelve relevant papers. |
| B．They conducted the study by categorizing. |
| C．They followed the CVD patients until they died. |
| D．They applied their findings to the CVD patients. |
| A．Doubtful | B．Objective | C．Positive | D．Critical |
| A．Alcohol drinking contributes to heart diseases. |
| B．Heart disease patients need popular dietary habits. |
| C．Proper alcohol intake may benefit CVD patients. |
| D．Alcohol helps reduce the risks of heaving diseases. |
【推荐2】Feel tired lately? Has a doctor said he can’t find anything wrong with you? Perhaps he sends you to a hospital, but all the advanced equipment there shows there is nothing wrong with you.
Then, consider this: you might be in a state of sub-health.
Sub-health, also called the third state or gray state, is explained as borderline state between health and disease.
According to the investigation by the National Organization, over 45 percent of sub-health people are middle-aged or elderly. The percentage is even higher among people who work in management positions as well as students around exam-week.
Symptoms include a lack of energy, depression, slow reactions, insomnia, agitation, and poor memory. Other symptoms include shortness of breath, sweating and aching in the waist and legs.
The key to preventing and recovering from sub-health, according to some medical experts, is to form good living habits, alternate work and rest, exercise regularly, and take part in open air activities.
As for meals, people are advised to eat less salt and sugar. They should also eat more fresh vegetables, fruits, fish because they are rich in nutritional elements—vitamins and trace elements—that are important to the body.
Nutrition experts point out that it is not good to eat too much at one meal because it may cause unhealthy changes in the digestive tract. They also say that a balanced diet is very helpful in avoiding sub-health.
1. When you are in a state of sub-health, you should ________.| A．stay home and keep silent | B．go to a doctor and buy some medicine |
| C．not consider it very serious | D．find out the reasons and relax yourself |
| A．they have used up their energy | B．they have lost their living hopes |
| C．they have more pressure in life and work | D．they have changed their way of life |
| A．keep on working regularly | B．go to sleep a bit earlier |
| C．form good living habits | D．take medicine if necessary |
| A．arrange by turns | B．cause to take place |
| C．make up for | D．keep away from |
【推荐3】With a rapidly increasing global population and the life expectancy of people increasing as well, the need to boost our immunity (免疫系统) has also increased simultaneously.
Maintaining a healthy sleep schedule
Today’s generation strives on binge-watching their favorite shows on various platforms.
Minimizing stress
There are numerous factors that lead to stress and scientists have come to appreciate the link between the mind and the body. Stress can cause a plethora of physical illnesses as well.
Regular exercise doesn’t necessarily mean you need to become a fitness freak. Exercise in a moderated amount on a daily or frequent basis will help improve your immunity. How? According to the U.S. National Library of Medicine, exercise flushes the bacteria out of our lungs. Regular exercise also increases the rapid circulation of white blood cells.
Maintaining a healthy diet.
A good diet is also vital in order to boost immunity. Different foods that have a good amount of natural nutrition should be consumed on a regular basis. There are plenty of foods and other sources of nutrition like tea, which can help strengthen the immune system. Similarly, easily available other sources of natural nutrients are ginger, honey, lemon, honey etc.
| A．Taking more exercise. |
| B．Keeping regular exercise. |
| C．But how can you boost you immune system? |
| D．Therefore, it is important to try to minimize stress. |
| E．Here are several simple ways to enhance your immune system. |
| F．All of these put together with help in maintaining a healthier body. |
| G．This may lead to a lack of sleep as they may be hooked on their screens. |
【推荐1】Hong Kong has recently witnessed the return of live concerts and large-scale events, attracting visitors from around the world. Are you also planning a trip? It’s time to dig out your Octopus card for convenient payment of transport fares and much more.
No Octopus card, no problem! The options for transport payment in Hong Kong have become more diverse and convenient in recent years. People can now pay for public transport using WeChat Pay, Alipay, bank cards or credit cards. And the Octopus card, which has a wide variety of uses, can now be put into the electronic mobile wallet and can be used even if your phone is out of battery.
Are you figuring out the best way to get to the city center from the airport? The Airport Express takes only 24 minutes to travel from the airport to downtown. If you want to get off the plane and go straight to Central district, the fast and comfortable Airport Express is the best choice.
The Airport Express platform is connected with the airport’s arrival hall and has multiple entrances. It takes as little as a minute for passengers to enter the platform from the arrival hall. The trains provide large luggage storage areas, as well as high-speed Wi-Fi and charging facility. More importantly, the Airport Express connects you with other MTR lines. Whether for business travel or sightseeing, the Airport Express can save you a lot of time.
In addition to the MTR and buses, Hong Kong’s public transportation system also includes the historic Star Ferry, Hong Kong Tramways and the Peak Tram. They have been around for many years, but their functionality and overall experience are as good as that of the new transport modes. In fact, they enhance the experience of tourists and are also popular with locals going to work, shopping or out on a date. To improve passengers’ experience, the Peak Tram has recently undergone a major renovation.
It’s been a while and now it’s time to say “Hello Hong Kong” again!
1. What can be learned about transport payment in Hong Kong?| A．Octopus card is a must to travelers. |
| B．Transport payment has greatly improved. |
| C．Travelers can not choose to pay online or not. |
| D．Travelers can still pay when their phones are power off. |
| A．Complex and time-consuming. | B．Confusing and costly. |
| C．User-friendly and highly-effective. | D．Complicated and outdated. |
| A．Octopus card can do nothing more than paying transport fares. |
| B．The Airport Express enables passengers to enter the platform quickly. |
| C．The Peak Tram is too old to compete with new transport modes. |
| D．Old transport modes have lost their edges despite their renovation. |
| A．To introduce Hong Kong’s public transport. |
| B．To illustrate the popularity of Hong Kong. |
| C．To advertise for Hong Kong’s public transport. |
| D．To recommend Hong Kong as a great tourist attraction. |
【推荐2】High-quality customer service is preached(宣扬)by many,but actually keeping customers happy is easier said than done.
Shoppers seldom complain to the manager or owner of a retail store,but instead will alert their friends,relatives,co-workers,strangers-and anyone who will listen.
Store managers are often the last to hear complaints,and often find out only when their regular customers decide to frequent their competitors,according to a study jointly conducted by Verde Group and Wharton School.
“Storytelling hurts retailers and entertains customers,” said Paula Courtney,President of the Verde Group. “The store loses the customers,but the shopper must also find a replacement.”
On average,every unhappy customer will complain to at-least four others,and will no longer visit the specific store. For every dissatisfied customer,a store will lose up to three more due to negative reviews. The resulting “snowball effect” can be disastrous to retailers.
According to the research,shoppers who purchased clothing encountered the most problems. Ranked second and third were grocery and electronics customers.
The most common complaints include filled parking lots,cluttered(塞满了的)shelves,overloaded racks,out-of-stock items,long check-out lines,and rude salespeople.
During peak shopping hours,some retailers solved the parking problems by getting moonlighting(业余兼职的)local police to work as parking attendants. Some hired flag wavers to direct customers to empty parking spaces. This guidance eliminated the need for customers to circle the parking lot endlessly,and avoided confrontation between those eyeing the same parking space.
Retailers can relieve the headaches by redesigning store layouts,pre-stocking sales items,hiring speedy and experienced cashiers,and having sales representatives on hand to answer questions.
Most importantly,salespeople should be diplomatic and polite with angry customers.
“Retailers who're responsive and friendly are more likely to smooth over issues than those who aren't so friendly,” said Professor Stephen Hoch. “Maybe something as simple as a greeter at the store entrance would help.”
Customers can also improve future shopping experiences by filing complaints to the retailer,instead of complaining to the rest of the world. Retailers are hard-pressed to improve when they have no idea what is wrong.
1. Why are store managers often the last to hear complaints？| A．Most customers won't bother to complain even if they have had unpleasant experiences. |
| B．Customers would rather relate their unhappy experiences to people around them. |
| C．Few customers believe the service will be improved. |
| D．Customers have no easy access to store managers. |
| A．can stay longer browsing in the store |
| B．won't have trouble parking their cars |
| C．won't have any worries about security |
| D．can find their cars easily after shopping |
| A．Manners of the salespeople. |
| B．Hiring of efficient employees. |
| C．Huge supply of goods for sale. |
| D．Design of the store layout. |
| A．exert pressure on stores to improve their service |
| B．settle their disputes with stores in a diplomatic way |
| C．voice their dissatisfaction to store managers directly |
| D．shop around and make comparisons between stores |
【推荐3】When we talk about famous UK writer Agatha Christie, it seems that her famous detectives Hercule Poirot and Miss Marple are must-reads. So, of course, are her best-selling novels Murder on the Orient Express (1934) and Death on the Nile (1937).
But when the readers around the world were asked to name their favorite Christie novel to mark her 125th birthday on Sept 15, And Then There Were None (1939) topped the list, reported The Guardian.
It may surprise you to learn that it is a crime novel without a detective. What it does have is suspense (n.悬念) and a very sinister (adj.邪恶的) atmosphere. It is “on a knife edge”, as Mathew Prichard, Christie’s grandson, told the newspaper.
Ten people get an invitation to come to a house on a small island near Devon in South West England. Nobody refuses these invitations since each one promises something the person wants: a job, a holiday, a chance to meet up again with an old friend .
These people are all responsible for deaths. Some are directly responsible, others are responsible because of what they did not do. Anthony James Marston, for instance, killed two children while driving dangerously. He did not feel guilty and actually complained when he was banned from driving. Another, Emily Caroline Brent, is a harsh person who threw out a young servant for becoming pregnant while unmarried. The servant later killed herself.
When they arrive at the house they are played a recording. The voice gives details of the wrongdoing of each of the guests. Starting with Marston, each is killed in a way that fits their crime. The series of deaths is completed with a hanging, “and then there were none”, as the title suggests.
Christie can be quite a predictable writer. Some of her stories are a little unoriginal. But this book is full of clever writing. Look it up to find out what this hugely successful mystery writer, the “Queen of Crime” as she was called, could do at her best.
1. All of the following are Agatha Christie’s works EXCEPT ______.| A．Queen of Crime |
| B．Death on the Nile |
| C．And Then There Were None |
| D．Murder on the Orient Express |
| A．The unique theme offered by Agatha Christie. |
| B．The criminal plot without a detective. |
| C．The attractive place shown in the novel. |
| D．The varied characters created by Agatha Christie. |
| A．no guests survive in the end |
| B．no detectives appear in the novel |
| C．there are no mysteries in the novel |
| D．nobody is to blame for the deaths of the guests |
| A．All the people in the novel have killed someone before. |
| B．Ten innocent people are killed on a small island. |
| C．The people in the novel accept the invitations because of something they are offered. |
| D．A detective finds out who is responsible for the people’s deaths in the end. |
