The best strategy for quitting smoking isn't the same for everyone – it depends on how quickly the body breaks down nicotine.
When nicotine has been processed, the amount circulating in the bloodstream drops and the smoker craves a cigarette. Therefore, it is believed that the faster the breakdown speed, the more intense and frequent a person's cravings will be.
In the biggest smoking addiction study ever carried out, a group of scientists in the US took blood samples from 1,240 smokers and analysed them to determine their rates of nicotine metabolism.
They then put each person on one of three quitting programmes – a nicotine patch, a drug called varenicline or a placebo pill – and analysed their success rates.
The results, published in the Lancet journal, revealed how people with a normal nicotine breakdown rate were twice as likely to quit when they used varenicline rather than nicotine replacement patches.
A different pattern was observed in fast metabolisers, who had similar success rates irrespective of the method they used. Nicotine patches were more favourable, however, since they had fewer side effects.
What this means, in terms of choosing a quitting method, is that if a person is aware of their nicotine metabolism speed, they are much more likely to choose a strategy that actually works. This would prove extremely beneficial - currently, around 60 per cent of quitters start smoking again within the first week of abstaining.
Smoking is also a huge cost to the global economy, with around around six million people dying from smoking-related diseases each year and $200bn being spent on healthcare costs annually.
Blood tests are already used to check for nicotine breakdown speed in research, but scientists believe they could be developed for wider use.
“If these tests are used, people could have a sizeable chance of success,” said Professor Caryn Lerman, one of the lead researchers in the study.
"For some people, with normal metabolism of nicotine, the chance of success might be low on the patches but could double if they take the pill, while for a third of the population with slower breakdown, cheaper patches might be best."
THE WORLD'S BIGGEST SMOKERS
Nearly 20 per cent of the world’s adult population smokes cigarettes, according to Tobacco Atlas. The latest data released by the research group shows how the biggest smokers are concentrated in Eastern Europe.
Serbia tops the list, getting through an average of 2,861 cigarettes per person per year. Following closely are Bulgaria, Greece and Russia.