http://newpaper.asia1.com.sg/news/story/0,4136,137566,00.html?DOES this man in this photo realise the damage he is causing to himself?
Probably not. He has just lit a joint.
He may be under the impression that he risks only the injuries smoking can normally cause.
But he is inviting a bigger danger because he is smoking cannabis.
A new study commissioned by the British government has found that a single joint raises the risk of mental illness by 41 per cent.
In Singapore, from today, first and second-time abusers of cannabis and cocaine will get a shot at rehabilitation.
This is so that don't have to bear the stigma of a criminal record.
These abusers had better read this report.
The British study also found that taking the drug regularly more than doubles the risk of serious mental illness.
Overall, cannabis could be to blame for one in seven cases of schizophrenia and other life-shattering mental illness, the journal Lancet reported.
The authors of the study, commissioned by the British Department of Health, said: 'Policy-makers need to provide the public with advice about this widely-used drug.
'We believe there is now enough evidence to inform people that using cannabis could increase their risk of developing a psychotic illness later in life.'
The researchers, from four British universities, analysed the results of 35 studies into cannabis use from around the world. This suggested that trying cannabis only once was enough to raise the risk of schizophrenia by 41 per cent.
At greatest risk, however, were heavy users, with those who took cannabis over 100 times having more than double the risk of those who never touched the drug.
With up to 40 per cent of teenagers and young adults in the UK believed to have tried cannabis, the researchers estimate that the drug could be behind 14 per cent of cases of schizophrenia and other psychotic illnesses.
Cardiff University researcher DrStanley Zammit told the Daily Mail: 'Even if cannabis does cause an increased risk of developing psychosis, most people who use cannabis will not develop such an illness.
'Nevertheless, we would still advise people to avoid or limit their use of this drug, especially if they start to develop any mental health symptoms, or if they have relatives with psychotic illnesses.'
In another study, by a team from the Medical Research Institute of New Zealand, it was found that a single joint of cannabis can damage the lungs as badly as smoking five cigarettes in one go.
Those who smoked cannabis damaged both the lungs' small fine airways, used for transporting oxygen, and the large airways, which blocked air flow, the researchers said.
A study of 339 adults up to the age of 70 found cannabis smokers complained of wheeze, cough, chest tightness and phlegm.