2 . 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.