in Britain, the National Health Service spends 10 billion pounds per year treating it,

that's almost 10% of the entire National Health budget.

By 2040, it's estimated that one in 10 people around the world will have the disease,

three decades of healthy lifestyle advice have failed to make an impact.

Could surgery be the answer?

Been a fisherman all my life.

I can't tell you how much I miss the sea,

I love my wife and children obviously,

but fishing is a passion, it isn't just a job.

Peter Hansell is 68.

A few years ago, he was diagnosed with type two diabetes.

When I was diagnosed, I didn't think it would have the restrictions it had on my life,

it just wasn't safe for me to be at sea,

so diabetes has stopped me working, which upsets me greatly.

Type two diabetes is a serious condition in which the body can't use insulin properly,

90% of people with diabetes have type two,

type one is much rarer and usually develops in childhood.

The prognosis is that parts of my body will deteriorate over time, my kidneys, my heart.

I've always had tons of get up and go,

but I'm afraid the get up and go has got up and gone.

Globally the number of people with type two diabetes has quadrupled in the past four decades,

it's been branded as a lifestyle illness brought on by poor diet and lack of exercise.

Obesity is a major risk factor,

but one doctor is convinced that the disease is misunderstood.

If it were as simple as telling people to eat less and exercising more,

we have been giving this message for the past 30 years

and as a result, we haven't seen any change and the epidemic has continued to grow.

Professor Francesco Rubino specializes in weight loss surgery,

he's performed hundreds of gastric bypass operations on obese patients, but Rubino has discovered that gastric surgery has a profound and unexpected side effect.

I found that many of the patients, who have bariatric operations would experience a complete remission of diabetes almost overnight,

to me, that was too much to be explained by weight loss alone and I thought what if there is something else?

Dr. Rubino is now going to operate on Peter,

not because he's obese, but to treat his diabetes by changing the anatomy of his gut.

Rubino believes that a section of the small intestine doesn't work properly in people with diabetes.

Peter's stomach will be divided and rerouted,

so that food no longer passes through the faulty section.

Something happens in the duodenum,

which contributes to the mechanism of diabetes and by bypassing that segment, we're bypassing what could be the source of the problem.

When food moves through the small intestine,

a complex hormone signaling system tells the brain to stop eating and stimulates the pancreas to produce insulin.

A fault in this signaling system would make it extremely difficult for the patient to control their eating

and could explain why the body can't regulate insulin properly.

Peter stands a very good chance of having a complete remission of diabetes

and this is an effect that was not even conceived as possible just until a few years ago.

The effect is so striking, that in 2016,

international medical guidelines were changed to include surgery as a main treatment option for some diabetes patients, but very few have come forward.

Despite the evidence, suggesting that these interventions are so effective and in many cases, they're lifesaving,

there are probably .1 to 1% of individuals, who meet the criteria for surgery who actually have access to it.

Type two diabetes is widely viewed as a lifestyle disease, that patients can control on their own without the need for surgery,

but Rubino believes this is a misconception.

Having an operation is not an experience that everybody would be prepared to have,

however the evidence we have so far has shown time and again,

or once you have very severe obesity,

changing your lifestyle alone is not going to bring the benefits that are needed.

In clinical trials,

Rubino is testing other ways to prevent food from interacting with the faulty section of the intestine,

such as plastic tubing or eradicating cells from the gut wall.

The hope is that in the future, patients like Peter won't need to have invasive surgery.

Seven weeks after the operation and Peter's health has taken a dramatic turn.

I just feel good, I can just do what I want, I've got a life again.

I can't thank Professor Rubino and his team enough for what they did for me,

I haven't took any insulin since.

For now at least, Peter's diabetes is in remission.

Surgery alone can't halt the epidemic,

diabetes rates are rising in almost every country,

but only a few have the resources for surgery.

Prevention through better diet and lifestyle is vital,

but if surgery can uncover the cause of diabetes, perhaps a cure will follow.