A man who guzzled up to three litres of cola every day, drank himself to  death.

An inquest heard how 30-year-old Paul Inman, who had Asperger’s syndrome,  would walk to the shops more than once a day to buy his fizzy drinks.

The huge quantities of cola, other pop and water caused his lungs to swell to  four times their normal weight.

He died in his sleep at a care home in Haworth, West Yorkshire.

Pathologist Dr Deirdre McKenna put his death down to his excessive drinking,  which began when he was 10-years-old.

He was suffering from a massive pulmonary oedema which meant the large amount  of fluid in his lungs restricted his breathing.

This was caused by Mr Inman’s non-medical condition of polydipsia, which is  Greek for “much thirst”, which in turn was a result of his Asperger’s.

His mum Alison told the coroner yesterday: “I’m not a pathologist but I made  that decision two hours after he died.

“I’ve said the cause of it was he drank excessively. He had done since he was  10. We used to say he had a self-destruct button.”

The inquest also heard how Mr Inman never stayed still – he could wear out  two pairs of trainers in a week.

Care staff had to keep his cigarettes so he would not smoke 20 in one  hour.

When he was 17 Mr Inman was diagnosed with schizophrenia – but when his case  was reviewed in 2008 doctors diagnosed that he suffered from Asperger’s, a form  of autism.

Bradford coroner Dr Dominic Bell, recorded a verdict that Mr Inman died of  natural causes.