There are 100,000 insulin-dependent people on the roads everyday, but they are not causing accidents

Stephen Fishwick, Diabetes UK

Speaking to BBC Radio Cornwall on Tuesday, Mr Clack said his taxi business is beginning to suffer.

"To see it (the business) slowly going down the drain is a bit disappointing," he said.

"We feel we provide a good service and we have built up a lot of satisfied customers in our town."

He said he is under no restrictions to drive when it comes to his own private car.

"I feel fine in myself, you know," he said. "Obviously the DVLA have got the same opinion because they haven't ask for my licence to be returned to them."

Dependence concern

However, Nick Hibbert, Restormel council's head of environmental services, said the public's safety must come first.

He said: "When it's insulin, the driver is effectively group two and that means he is similar to a lorry driver.

"And the requirement is that if you are injecting insulin, you are therefore insulin dependent and the recommendation is that you should not be driving a private hire vehicle or taxi."

Stephen Fishwick, Diabetes UK's national campaigns manager, said by operating a blanket ban an authority could be putting the public at more risk.

Warning signs

He said: "There are 100,000 people who are dependent on insulin and are on the roads everyday, but they are not falling asleep at the wheel and causing accidents.

"By operating bans like these, it's conceivable that many people won't reveal their condition to employers and that's much more worrying."

Mr Fishwick said as long as a diabetic is fully aware of their condition, they get warning signs like headaches and nausea, long before their driving is affected.

"We're hoping attitudes will change, because there is nothing to justify treating people like this," he said.