The benefits of quitting smoking—reduced risk of cancer and many other health problems—are known. But for millions of smokers, the【D1】 1effect of a cigarette can be reason enough to start up again.
Studies have found, however, that in reality, lighting up has the【D2】 2effect, causing long-term stress levels to rise, not fall. For those dependent on smoking, the only stress it【D3】 3is the withdrawal between cigarettes.
In a recent study【D4】 4at the London School of Medicine and Dentistry, researchers looked at 469 people who tried to quit after being【D5】 5for heart disease. At the start, the subjects had similar levels of stress and generally believed that smoking helped them to cope. A year later, 41% had managed to stay abstinent(节制的). After controlling for many a【D6】 6, the scientists found that the abstainers had "a【D7】 7larger decrease in perceived stress," roughly a 20% drop, compared with the continuing smokers, who showed little change.
The scientists'【D8】 8was that the continuing smokers were dealing with uncomfortable cravings(渴望)between cigarettes multiple times a day, while the abstainers, after facing some initial withdrawal, had greater freedom from nicotine cravings and thus had【D9】 9a frequent and significant source of stress. Other studies have also found that smokers experience higher levels of stress and【D10】 10between cigarettes and lower levels over all when they quit.
A)relieves F)suffered K)conducted
B)summary G)factor L)hypothesis
C)calming H)eliminated M)negative
D)tension I)opposite N)hospitalized
E)significantly J)causes O)dominantly 【D1】