A new saliva test that determines smoking history for the last three days in just five minutes will make life difficult for smokers to lie or hide their habits.

The 'Saliva SmokeScreen test' designed by the University of Birmingham researchers can be employed in hospitals and health insurance companies. The test works by detecting cotinine, a metabolite (broken down product) of nicotine, in saliva. Cotinine is normally used as a marker of nicotine exposure.

The test cannot reveal the number of cigarettes a person has consumed or what kinds of them have been used. However, it accurately shows the nicotine levels consumed over the last three days.

The test will be positive for people who are also using nicotine replacement products.

 "Smoking is an important risk factor for many chronic diseases, such as respiratory diseases, cardiovascular disease and diabetes. It also causes blood pressure to rise and is linked with high cholesterol levels," Dr Graham Cope, honorary senior research fellow, said in a statement.

Previous studies showed that smoking leads to sleep deprivation, depression and anxiety, cognitive decline and mood disorders.

Dr. Prabhat Jha, director of the Centre for Global Health Research of St. Michael's Hospital, and his team of researchers, argue that the only way of reducing the increasing number of smokers and deaths (lung cancer and other related diseases) worldwide is by tripling tobacco taxes.

The strategy that has already been implemented in France has shown remarkable results. The tobacco use reduced by half from 1990 to 2005 due to the increase in tax rates, which rose above inflation.

"Death and taxes are inevitable, but they don't need to be in that order," Jha said in a press release. "A higher tax on tobacco is the single most effective intervention to lower smoking rates and to deter future smokers."

Researchers claim that tobacco tax can help lower smokers' population by one-third and prevent nearly 200 million premature deaths.

"..... tobacco taxes are a hugely powerful lever and potentially a triple win - reducing the numbers of people who smoke and who die from their addiction, reducing premature deaths from smoking and yet, at the same time, increasing government income," Sir Richard Peto, of the University of Oxford and the study co-author, said.