There is not enough evidence to conclude that e-cigarettes helps smokers quit tobacco, a US government report said Thursday, as the vaping industry faces increased regulatory pressures. The advice is contrary to that provided by the British government, which classes e-cigarettes as a nicotine replacement therapy that makes smoking cessation attempts more likely to succeed. “E-cigarettes, a continually changing and diverse group of products, are used in a variety of ways,” said the report on Smoking Cessation issued by the Surgeon General, the first on the topic since 1990. “Therefore, it is difficult to make generalizations about efficacy for cessation based on clinical trials involving a particular e-cigarette. There is presently inadequate evidence to conclude that e-cigarettes, in general, increase smoking cessation.” The report did say, however, that cessation medications approved by the Food and Drug Administration, such as nicotine patches and lozenges, as well as counseling, “increase the likelihood of successfully quitting smoking, particularly when used in combination.” The advice comes weeks after the US government announced it was banning most flavored e-cigarettes in a bid to curb the rising tide of youth vaping, but under industry pressure it stopped short of the full ban promised in September by the White House. The FDA said cartridge-based e-cigarettes in flavors other than tobacco or menthol would be illegal unless specifically authorized by the government. The change will take effect in early February, outlawing cartridges with fruit, mint and candy flavors, which are particularly popular with young people. Juul, the e-cigarette industry leader, had anticipated the decision and withdrew those flavors from sale in the US, leaving only tobacco and menthol. The ban will exempt large, tank-based rechargeable vaping devices, however, which are primarily sold in vape shops that cater to adults. The report found that although cigarette smoking among American adults is at an all-time low (14 percent), it remains the leading cause of preventable disease, disability and death in the United States. Approximately 34 million American adults currently smoke cigarettes.