Most of us in the West are an unhealthy lot: we eat junk food, drink too much alcohol, exercise too little and generally ignore medical advice designed to help us live longer.
But there is one thing we are listening to our doctors about. Smoking rates have been slowly falling, year on year, in most Western countries for decades. This month saw the 10-year anniversary of England's ban on smoking in enclosed workplaces - including bars and restaurants - a change that once would have seemed inconceivable. The UK government is due to announce new tobacco control strategies for the next few years.
The decline of smoking is emboldening some public health officials to plan for what is sometimes called the tobacco endgame - stubbing out smoking completely. But several strategies to reach this goal have potential pitfalls, and some could even be counterproductive. So is a smoke-free future ever going to happen, and what could we do to bring it about?
Smoking was a minority pursuit until the late 19th century and the arrival of one of the deadliest inventions in history: industrially produced cigarettes. Their popularity soared during the first world war, as soldiers were given cigarettes with their rations. Celebrities, athletes and even doctors endorsed the habit. At its peak in the mid-20th century, around half of all adults in the UK and the US smoked.
But the evidence was building that smoking causes lung cancer, as well as heart attacks, strokes and other diseases. The risks were denied by tobacco companies for decades, but the tide of public opinion was turning. As governments brought in an increasing array of tobacco control measures, from health warnings on cigarette packs to advertising bans and restrictions on where people can light up, smoking rates have slowly declined.
A long-standing fear, however, has been that the fall would stop because of a hard core of smokers impervious to all health advice. "People always used to say you can never get below 25 per cent," says Martin Dockrell of Public Health England.
"In the UK, adult smoking rates are now down to about 16 per cent, in the US, 15 per cent"
But this hasn't happened. In the UK, adult smoking rates are now down to about 16 per cent, in the US, 15 per cent. So how long could this trend continue?
Some think there is practically no limit, including Stanton Glantz at the University of California, San Francisco, a long-time tobacco control crusader. He says that while smoking will never be completely wiped out, the habit could be eliminated "as a public health problem of substantial consequence" - in other words, smoking rates could be reduced to just a few per cent.
Some countries already have this goal in sight. New Zealand, which has long had some of the world's strictest tobacco control laws, aims to get adult smoking down to below 5 per cent by 2025. Finland is aiming for this by 2030, including the use of chewing tobacco and e-cigarettes.
A Plan To Ban
But is this goal enough? Despite all the health warnings, some argue that people assume cigarettes can't be that bad if you can still buy them everywhere. Perhaps a full ban is the only way to get the message across.
To date, only one country has dared go this far. In 2004, the Himalayan nation of Bhutan outlawed the sale of all cigarettes and chewing tobacco. People can buy them legally abroad, but there is a limit on what they can bring into the country.
Western nations probably shouldn't look to Bhutan's ban as a guide, though, as even before it came in, the country's smoking rate was estimated at just a few per cent. It is also very different culturally. The main religion is Tibetan Buddhism, which encourages people to keep a clear mind so they can meditate, says Michael Givel at the University of Oklahoma. "Tobacco hasn't been as big a cultural thing as elsewhere."
Aside from the question of whether it is ethical to stop people doing something they enjoy, this kind of ban may also backfire. History tells us that prohibition fuels criminal suppliers. This happened in the 1920s when alcohol sales were banned in the US, and still goes on today with illegal recreational drugs such as heroin.
"There are all sorts of scary unintended consequences that could come along with prohibition," says Dockrell. Use could even increase, he says, as illicit cigarettes would be much cheaper and lack health warnings.
"You're much more effective at regulating products if they're legal," says Deborah Arnott of UK anti-smoking group Action on Smoking and Health.
It's hard to know the effect of the ban in Bhutan as there is no reliable data, but seizures of smuggled tobacco in the country rose more than three-fold between 2005 and 2008. "If anyone claims they can get rid of smoking based on the Bhutan model, the evidence is fairly to the contrary," says Givel.
There are other strategies on the table. One sometimes floated is the introduction of a minimum age for buying cigarettes that rises each year. Existing smokers could carry on, but youngsters wouldn't legally be able to start.
Such a law has been debated in the Tasmanian parliament in Australia, although it has never been introduced anywhere, partly because it raises the same problem of fostering a black market for those under the age limit.
Others have suggested forcing the tobacco industry to alter the make-up of cigarettes, such as making them slightly more alkaline to deter deep inhalation. This would make them more like the harsh old-style "gaspers", as cigarettes used to be known in the UK. But again, milder, black-market cigarettes would win out.
"In 2004, the nation of Bhutan outlawed the sale of all cigarettes and chewing tobacco"
The best approach, says Glantz, is to continue raising taxes, and further restrict advertising and where people can smoke in public. The next target should be cutting out smoking in movies and other media, he says, perhaps by giving any films that contain smoking a high age rating. Studies show that the more that teenagers see smoking on screen, the more likely they are to take it up. "It's a bigger effect than conventional advertising," says Glantz.
And what about those who really don't want to give up smoking? They may be able to wean themselves off using e-cigarettes. Since they were first mooted, these devices, which vaporise nicotine without producing smoke, have divided public health experts. In most of the West, particularly the US and Australia, the mainstream view is that they are almost as dangerous as ordinary cigarettes.
In the UK, on the other hand, vaping is increasingly seen as a useful aid to help people quit smoking, like nicotine gum. Public Health England says e-cigarettes are 95 per cent safer than smoking, and that we should consider letting people vape in places where smoking is banned - sometimes even indoors.
"There's no evidence of harm to bystanders, and by prohibiting vaping you might undermine people's attempts to give up smoking," says Dockrell. He would even like to see doctors be able to prescribe e-cigarettes on the NHS.
One study illustrates how vaping has been shown to reduce carcinogens by almost 98 percent in former smokers who dropped their cigarette habit and switched to vaporizers.
The latest UK figures also seem to contradict the idea that e-cigarettes are a gateway to smoking. Vaping took off around 2010, and since that time the rate of decline in smoking has, if anything, slightly steepened. On the other hand, smoking rates are falling in the US and Australia, where vaping is more frowned on. Perhaps in a few years' time, we will know which approach is right.
Glantz predicts that as smoking continues to fall, it will become less socially acceptable to light up when among non-smokers or even just out in public. Studies suggest that smoking bans in indoor workplaces help people to keep their own houses smoke-free, even if they smoke themselves. "The current policies are working," he says. "We just need to do them more."