3 . One of the presents in my house this Christmas was a late 18th-century volume of the Encyclopaedia Britannica (大英百科全书). It is a window into the discoveries and thinking of the time. The encyclopaedia is an entertaining reminder of how _______ some of our current truths are bound to be. Certainties in areas we haven’t yet understood will look just as ridiculous as some of these in centuries to come. And one of those we are still remarkably _______ is the effect of food and exercise on our bodies. We’re surrounded by confident _______ on how to eat, how to avoid or reverse obesity (肥胖), and yet the advice seems pointless while the world gets fatter. Much of what we think we know is a pile of assumptions rather than _______ .

Our confusion is the theme of Spoon-Fed, a book by one of Britain’s leading nutrition researchers, Tim Spector of King’s College London. Its subtitle is: “Why almost everything we’ve been told about food is wrong.” It is a call for us to _______ more.

One by one Spector offers answers to recent food _______. Coffee can save our lives, he says. Three to four cups a day reduces the risk of heart disease and may cut the risk of death by 8 per cent. Butter does not damage our hearts, Spector argues, and salt is vital. Eggs have gone “from heroes to villains and back again”. Don’t say no to all red meat on _______ grounds; occasional small quantities of high-quality unprocessed meat provide important vitamins and iron and are “probably good for you“. Exercise is so good for longevity and happiness that it should be considered our No 1 drug, but the one thing for which it’s _______ useless is losing weight. Vitamin pills are a multibillion-pound industry with almost no proven _______ but which can cause real harm. Even vitamin D, which Spector used to study and believe in, he now _______.

Spector also offers more than a set of currently _______ tips. The science of nutrition has not been solved by him, as he would be the first to admit. His most _______ point is that there is no one size that fits all. Our bodies are complex, and our reactions are _______: yet nobody wants to pay for the research that might explain why.

Some combination of food choices, genes, environment and the chemical reactions generated by our microbiome — the unique microbe (微生物的) combinations in our body ― yes different _______ for each of us, leaving some lean and two thirds of us too fat. This is the territory Spector wants to explore further and which might just allow us to _______ the global trend to obesity, with all the risks we’ve witnessed this year.

4 . Do you like to exercise?     1     Do you prefer playing a team sport, like volleyball or baseball? Or do you like to run for miles and miles all by yourself? Maybe you would rather lift weights or do push-ups or sit-ups!

You know that exercise is good for your body. It helps you grow stronger. It can also help keep your heart and other important organs in excellent shape. But can it make you smarter?

Maybe! The work you do at school every day is like exercise for your brain. Learning and thinking can help you become smarter.     2    

Some researchers point out that exercise stimulates the body’s nervous system, causing it to release chemicals that make us feel happy and calm. This helps to explain why many people feel more alive and active after exercising.     3     On the whole, you can work or study at a higher level after exercise.

Others point to studies that show that exercise can stimulate the growth of new brain cells. As your brain gets bigger, the areas in connection with memory and learning get bigger and brain function improves.

    4     Experts believe that as little as 15-30 minutes per day three times a week may be enough to improve brain performance. Thirty to sixty minutes per day four to five times a week is even better.

Exercise is good for your body in so many ways, so include as much exercise as you can into your daily or weekly routine.     5    

5 . Are you sitting more than ever?     1     You’re probably sitting while reading this. Sometimes you sit when you are driving or attending a meeting. Other times you sit when you engage yourself in watching a movie or playing computer games. That’s undoubtedly a lot of sitting. The fact is, the amount of time spent sitting has increased over time.     2    

We know sitting too much is bad, and most of us naturally feel a little guilty after a long-time TV watching.     3     A study on nearly 8,000 adults suggests that there’s a direct relationship between the time spent sitting and our risk of early death of any cause. As the total sitting time increases, so does the risk of early death.

“Sit less, move more” is what the Heart Association encourages us to do.     4     It is like telling someone to just ”exercise“ without telling them how. Exercise guidelines are always more practical. For example, the Center for Disease Control recommends adults do exercise for two hours and 30 minutes every week, plus muscle strengthening activities two or more days a week. We need similar guidelines for sitting.

    5     “It would probably be like, for every 30 continuous minutes of sitting, stand up and move or walk for five minutes at a quick pace,” Diaz, the lead researcher said, adding that the study has put us a step closer to the satisfying guidelines. But more researches are needed to confirm their approach.

8 . It’s truly never too late to begin exercising, according to the researchers led by Pedro Saint-Maurice of the U.S. National Cancer Institute. Even for people who were “couch potatoes” in their youth, starting regular exercise in middle-age can still greatly cut the probability of death from any cause.

The study tracked the lifetime exercise patterns of more than 315,000 people. The investigators found that folks who’d exercised all their lives had a 36 percent lower risk of dying during the study period, compared to people who’d never exercised. But, perhaps surprisingly, people who’d been inactive in youth but decided to get more physical in their 40s and 50s saw almost the same decline—35 percent—in their probability of an early death.

The study also found that a mid-life start to physical activity seemed to cut the probability of death from the two major killers—heart disease and cancer. For people who began exercising in their 40s and 50s, rates of death from heart disease fell by 43 percent compared to people who’d never exercised, and the cancer death rate fell by 16 percent. Those declines were similar to those seen in people who’d exercised all their adult lives.

“This study, once again, indicates the importance of physical activity in relationship to one’s long-term mortality,” said Dr. Evelina Grayver. “Whether or not you start exercising when you are younger or older, the benefits will always be there. But starting exercising at a later age and still getting the same mortality benefit doesn’t mean that one should not exercise in younger years. Overall effects of continuous physical activity decrease the risk of an early death.”

The researchers also noted that while other research linking exercise to longevity has looked at physical activity at just one point in the lifetime, theirs is the first to examine the role of “participation in physical activity throughout the different stages of adulthood.” This new research demonstrates the crucial relationship between physical activity and the prevention of death at any age.