Type 2 diabetes can be reversed by going on a low calorie diet, new research shows.
Consuming just 600 calories a day for eight weeks can save the lives of millions of sufferers of the preventable condition.
Newcastle University scientists said that excess calories lead to a fatty liver, which causes the liver to produce too much glucose.
The excess fat is then passed to the pancreas, which causes the insulin-producing cells to fail and thus causing diabetes.
Losing less than one gram of fat from the pancreas can re-start insulin production, reversing type 2 diabetes, the researchers found.
Consuming just 600 calories a day for eight weeks can save the lives of millions of sufferers of type 2 diabetes, scientists claim
This reversal of diabetes remains possible for at least ten years after the onset of the condition, lead author Professor Roy Taylor said.
Such a diet helps bring about 15kg of weight loss on average. Weight loss has long been known to help reverse the condition.
It's down to the patients
Professor Taylor, who has spent almost four decades studying the condition, said: 'I think the real importance of this work is for the patients themselves.
'Many have described to me how embarking on the low calorie diet has been the only option to prevent what they thought - or had been told - was an inevitable decline into further medication and further ill health because of their diabetes.
'By studying the underlying mechanisms we have been able to demonstrate the simplicity of type 2 diabetes.'
What did the study find?
The study showed results within just a week of starting the diet. It caused a profound fall in insulin sensitivity.
Fasting blood sugar levels, of which diabetes patients have significantly higher, became normal within the same time frame.
Often thought of as harmless, type 2 diabetes is a hidden killer and can lead to heart failure, blindness, kidney disease and leg amputations.
Figures suggest there are 380 million sufferers worldwide. In Britain this has topped 3.8 million, an amount that continues to rise.
Professor Taylor said: 'The good news for people with type 2 diabetes is that our work shows that even if you have had the condition for 10 years, you are likely to be able to reverse it by moving that all important tiny amount of fat out of the pancreas.
'At present, this can only be done through substantial weight loss.
More than a third of type 2 diabetics aren't taking their life-saving drugs, a major new review found last week.
Experts said patients who are failing to take their medication, which can significantly reduce the risk of death, are at risk of 'dramatic consequences'.
The Leicester Diabetes Centre study was based on medical records of more than 318,000 sufferers of the preventable condition.
It suggested that many of the 380 million sufferers worldwide are confused about the sheer amount of drugs they have to take on a daily basis, including metformin which lowers blood sugar to prevent life-changing complications.
How does the diet work?
Professor Taylor added: 'Work in the lab has shown that the excess fat in the insulin producing cell causes loss of specialised function.
'The cells go into a survival mode, merely existing and not contributing to whole body wellbeing, but removal of the excess fat allows resumption of the specialised function of producing insulin.
'The observations of the clinical studies can now be fully explained, and surprisingly, it was observed that the diet devised as an experimental tool was actually liked by research participants.
'It was associated with no hunger and no tiredness in most people, but with rapidly increased wellbeing.’
What do the experts say?
Experts welcomed the 'great' findings, which were presented at the European Association For The Study Of Diabetes in Lisbon.
Professor Kamlesh Khunti, of the Leicester Diabetes Centre, said: 'This is great research and shows that low calorie diets can work in highly-motivated people, however, this would be difficult to implement widely for most people.'
Dr Elizabeth Robertson, Diabetes UK director of research, said: 'Evidence is building to suggest that Type 2 diabetes can be put into remission - a step forward that could be transformative for millions of people.
'But we don't yet have all of the answers we need, such as whether remission is achievable for everyone, or for the long-term, or how best to monitor those who do achieve remission.'
The 5:2 diet: aka The Fast Diet, the best known of the fasts and was made famous by Dr Michael Mosley.
Comprising of five days of regular eating and two ‘fast’ days of 800 calories, it has been associated with improved DNA repair and brain function.
An increase in fat loss was also demonstrated in a 2011 Manchester University study.
Dr Mosley lost 20lb in 12 weeks and saw his blood sugar and cholesterol levels return to normal after being pre-diabetic.
What is type 2 diabetes?
Type 2 diabetes is caused by having too much glucose in the blood because the body's way of turning it into energy is not working properly.
As the condition progresses, sufferers often need to maintain a healthy diet, exercise and a combination of medications to manage it.
Controlling blood sugar levels are also considered to be the key to reducing the risk of life-changing complications for those already diagnosed.
Someone's life expectancy with type 2 diabetes is likely to be reduced as a result of the condition, by up to 10 years, it is believed.