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DNA testing won't guide dieters to the weight-loss regimen most likely to work for them, scientists reported on Tuesday. The most rigorous study so far found no difference in weight loss between overweight people on diets that “matched” their genotype and those on diets that didn't.
The results underline “how, for most people, knowing genetic risk information doesn't have a big impact,” said Timothy Caulfield, of the University of Alberta, a critic of quackery. “We know weight loss is tough and sustained weight loss is even tougher. Genetics are relevant…but it seems highly unlikely that providing genetic risk information is going to be the magical formula that is going to fix this complex problem.”
The study randomly assigned 609 overweight adults, aged 18 to 50, to either a healthy low-fat or healthy low-carb diet. The volunteers got 22-hour-long classes with dietitians on healthy low-fat diets or low-carb ones, as well as on the dangers of eating mindlessly. Both groups were instructed to eat lots of vegetables and very few foods with added sugars, trans fats, or refined flour. There was virtually no difference in weight loss between the two groups after 12 months: 11.7 pounds in the low-fat group and 13.2 in the low-carb one, a difference that was not statistically significant or meaningful in real life.
The researchers then analyzed weight loss among people whose DNA “matched” or clashed with their assigned diet. That was based on which variants of three genes—called PPARG, ADRB2, and FABP2, which are involved in processes such as fat and carbohydrate metabolism—they had. Earlier research suggested that these variants could predict who would successfully lose weight on which kind of diet.
Of the 244 people with the low-fat genotype, 130 happened to land in the low-fat diet group, meaning they were on the “right” diet for their DNA. That was the case for 97 of the 180 people with the low-carb genotype. The others were mismatched.
“There was no significant difference in weight change among participants matched vs mismatched to their diet assignment,” the researchers wrote. There was also no DNA/diet interaction for waist circumference, body mass index, or body fat percentage.
6. According to the first paragraph, overweight people with diet matched to their DNA ______.
[A] succeed in losing more weight
[B] fail to achieve any weight loss
[C] have tried many types of diets
[D] show no signs of better effect
7. Why the low-carb diets and low-fat ones are mentioned in Paragraph 3?
[A] To prove that the low-carb diet is more effective in weight loss.
[B] To demonstrate the dangers of unhealthy eating habits.
[C] To verify the causal relationship between genotype and diet.
[D] To show that genetics is overestimated as a fix to overweight.
8. According to Paragraph 4, variants of PPARG, ADRB2, and FABP2 were previously used to ______.
[A] estimate whether a diet could work for certain people
[B] predict fat and carbohydrate metabolism in weight loss
[C] provide a successful solution to weight loss
[D] function as an honest indicator of people's weight
9. It can be inferred from the last two paragraphs that ______.
[A] 97 of the 180 with the low-carb genotype were on the mismatched diet
[B] DNA/diet interaction could be found in many body indices
[C] participants with matched diet lost similar weight to those without
[D] the low-carb group came up with different results from the low-fat one
10. Which of the following is the best title for the text?
[A] Matching DNA to a Diet Does Not Work
[B] Overweight Adults Try to Lose Weight
[C] Low-Fat and Low-Carb Diet Take Effect
[D] Variants of Three Genes Call for Attention
“Overlawyered” is the name of a widely read blog on America's legal system, and many Americans feel that way. Yet one economist thinks the country is actually plagued by too few lawyers, not too many. Clifford Winston published a book last month arguing that barriers to entry have kept the number of lawyers artificially low for decades. This—combined with an economy over-regulated by lawyers who go on to politics—results in an unearned premium on legal wages.
Three supply barriers bulk largest. The American Bar Association accredits law schools, and in most states you must be a graduate of one of them to practise law. The author notes that Abraham Lincoln, who practised for decades, and Clarence Darrow, perhaps the most celebrated criminal defender in American history, did not graduate from law school.
The second hurdle for a would-be lawyer is the bar exam itself. Proponents say it acts as a useful quality control. Opponents say it is a gruelling but useless ritual. In 2005 the dean of Stanford University's law school, going into private practice, failed it on her first try. So did Benjamin Cardozo, a 1930s Supreme Court justice and prolific scholar, who today has a law school named after him. Today students pay thousands of dollars to study for their bar exams, even after they have finished law school. But even after they pass, the bosses of legal firms note that new hires still need to be taught nearly everything about actual practice on the job.
Finally, American states do not allow non-lawyers to manage or invest in law firms, nor can companies not run by lawyers practise law in any form. Mr. Winston thinks that—in a more sensible world—banks, consultancies, accountancies and others could hire lawyers and offer a full range of services, including legal ones. And those without the bar exam or law school under their belt could still, with training and experience, dispense routine guidance and offer legal services, such as drafting wills and arranging simple divorces, to poorer clients. Doing so today risks getting a false “lawyer” sent to prison.
Clifford Winston acknowledges that the most complex matters will still go to the best-educated and qualified lawyers. Quality control is always imperfect; the current qualification system, after all, lets both incompetent and unethical lawyers through. Mr. Winston says that oversight would be a much better method than restrictions on supply. Many clever people are bad at taking tests, or are not able to spend $150,000 on law school. The question is whether the tens of billions of dollars being wasted on the current system are an acceptable cost for keeping a few bad lawyers, alongside many decent ones, from offering their wares.
11. We can learn from Paragraph 1 that ______.
[A] Americans get to know their legal system by blogs
[B] there is serious corruption in the bar exam in America
[C] lawyers in America earn more because of their small quantity
[D] lawyers in America do not earn much on their legal cases they work on
12. Abraham Lincoln and Clarence Darrow are cited in Paragraph 2 to show that ______.
[A] the learning experience in law schools is useless
[B] practical experience makes a lawyer perfect
[C] law school study is not indispensable to lawyers
[D] able men are destined to achieve their goals
13. The author believes that the bar exam is ______.
[A] a mere formality and insignificant in practical work
[B] an effective way to select promising lawyers
[C] set for the purpose of making money with its high fees
[D] criticized by the bosses of law companies
14. The author tries to convey in Paragraph 4 that ______.
[A] it's illegal for non-lawyers to practise law in any case
[B] the legal system in America is very rigorous
[C] people should be careful of false lawyers
[D] qualified lawyers must go to law schools or take bar exams
15. It is suggested in the last paragraph that ______.
[A] it's better to control the number of lawyers than loosen restrictions
[B] people should check the qualification of lawyers before hiring them
[C] poor students should be charged less when taking bar exams
[D] the current qualification system should be improved urgently