Diabetes is a common problem in the UK, however those with type 1 make up just ten per cent of sufferers.
One of them is James Norton who was diagnosed with the condition ten years ago.
The 32-year-old actor, best known for his roles in Granchester and the BBC’s adaptation of War and Peace – and who is rumoured to be the next James Bond – recently spoke about how the diagnosis has affected his career and lifestyle.
He told the Daily Telegraph: “It’s interesting being on stage or on set because your body is full of adrenaline and that screws up your sugar.
“Especially when I’m on stage for a full hour and a half.
“I have to anticipate it at the beginning of the show and make sure my sugar levels are going up or are at least stable.”
Type 1 diabetes affects sugar levels by causing them to rise too high in the bloodstream.
It is usually spotted at a young age, but Norton revealed he was 22 when he was told he had it.
Type 1 usually runs in families, and both Norton’s mother and sister have the condition too.
As well as injecting insulin several times a day to help move sugar from the blood into other body tissues, he ensures he has quick access to sugar during a play should he need.
“In period plays, I’ve had to stitch little pockets in my costume for sugar tablets,” he said.
Norton revealed that he was once given a fizzy drink in a teacup in the middle of a play because a co-star thought he was falling into diabetic shock.
Diabetic shock – or hypoglycaemia – happens when there is too much insulin in the body.
If left untreated it could lead to a diabetic coma, brain damage or death.
Symptoms of type 1 include feeling very thirsty, tired, losing a lot of weight and passing urine more often than usual.
According to the NHS, they usually develop very quickly in young people over a few days or weeks.
However, in adults they make take several months to develop.