Go-karting champ turned body builder Jon Daltrey died after injecting himself with a diabetic drug bought over the web, believing it would help his training.

A CORONER has warned bodybuilders to avoid performance-enhancing drugs after a 25-year-old former British go-karting champion died from an insulin overdose.

Jon Daltrey, of Gorse Hill, was a fitness fanatic who died in his sleep on December 9 last year.

His death was a mystery because he did not smoke, take recreational drugs or suffer from any illness.

But Swindon Coroner's Court heard yesterday that the anabolic steroid nandrolone and insulin was found in his body, despite the fact Jon was not a diabetic.

The post mortem found he had died from an insulin overdose.

The inquest heard he had been using the drugs for months, but it was impossible for doctors to say exactly how long.

He had given up motor racing because his weight had increased, making him less competitive, and decided to concentrate on bodybuilding, visiting gyms four or five times a week. Insulin is taken by some bodybuilders before working out because it releases blood sugar and is highly effective at building muscle.

Swindon and Wiltshire deputy coroner William Bache warned bodybuilders that it was wrong to believe they could use such substances safely.

Recording a verdict of accidental death he said: "If any good is to come out of this it might be to serve as a warning to others who follow the same route.

"Those who make substances available to consumers on illegal markets do them no service whatsoever."

The inquest heard Jon was discovered on December 9 by his father Dave at the home they shared in Cricklade Road.

Vials of insulin, a syringe, a receipt for insulin bought over the internet from American firm Diabetics Express, and muscle-building protein powders were all found in his home.

In 1998 Jon won the British Go-karting Championship and raced against Jenson Button, who is now a Formula One driver.

He had worked as a precision toolmaker at Wilson Tool International in South Marston since leaving Dorcan School.

He left behind parents Sue and Dave, brother David and sister Sarah.

At the time of his death the Evening Advertiser reported he was a regular at gyms in the town including Club 2000 and Fitness First.

Speaking outside after the inquest his father said: "Jon was a fun-loving guy and he made a mistake.

"I would tell anyone thinking of using such drugs to be normal. God made you and you don't have to change yourself, it's not your looks it is what you are inside that matters.

"He was one of my greatest friends. He had too much to live for."

Jon's mother Sue, 46, from Covingham, who is separated her husband, said outside the court: "If only this can stop someone making the same mistake.

"It is not just Jon this has hurt, it has devastated the whole family.

"Someone told him this was a good thing to take. I wonder how people can get away with selling this to people who do not need it?"