Cannabis ages lungs

Cannabis users in their 20s and 30s have lungs like those of 60-yearolds who have smoked cigarettes their whole lives.

The discovery has led to fears of a chronic lung disease epidemic among young adults who are smoking more of the drug - in more powerful doses - than ever before.

Poisons expert Prof John Henry established the link after treating patients with collapsed lungs.

'They were suffering from a type of emphysema you would not, in a million years, expect to see in someone in their 20s or 30s - even if they were a cigarette smoker,' he said. 'You would not expect to see lungs like these until a smoker was about 60.

'When I questioned them, they all admitted to having smoked cannabis for about eight to ten years. It was very disturbing.'

He added: 'Particularly worrying is that one or two said they smoked only a couple of times a week.'

Because healthy people can also suffer collapsed lungs for no obvious medical reason, Prof Henry thinks hundreds of cannabis-induced cases are being overlooked.

In a speech last night to the Royal Society of Medicine, he warned of the dangers of greater tolerance.

'It could lead to thousands of young adults being damaged for life before they are middle-aged,' said Prof Henry, based at St Mary's Hospital in Paddington, West London.

'People ought to be warned. With cannabis you can damage your lungs in about 25 per cent of the time it takes if you use tobacco.'