Type 2 diabetes is caused by the body becoming resistant to the hormone insulin, resulting in a gradual rise in blood glucose levels. People who are overweight and not physically active are more at risk, particularly those with lots of fat around the abdomen. Longer term, the condition can lead to greater risk of heart attacks, kidney damage, blindness and damage to blood vessels in the legs and feet, which may even have to be amputated.
There are several drugs that boost insulin production - but when these stop working, patients have to inject themselves with the hormone itself. One of the leading proponents of the new dietary approach is Dr Fedon Lindberg, a Norwegian endocrinologist who has treated more than 18,000 diabetic patients in his four clinics in his home country.
"My experience with type 2 diabetic patients is that a balanced low-glycaemic diet coupled with a healthy lifestyle can reverse the disease," he says. "We have had many patients coming to us who were injecting high doses of insulin, as many as 200 units daily, who have managed to quit insulin and come off medications for blood pressure and other conditions." One of his patients, Hannermor Hultqvist, a retired nurse, weighed 19 stone and was injecting 150 units of insulin a day when she arrived at Dr Lindberg's Oslo clinic. "I'd had type 2 diabetes for ten years and I was following the official low fat diet advice," she says. "Within eight months of following Dr Lindberg's recommendations, I stopped taking insulin. Now I've lost seven stone and my blood sugar is normal. When I first told my doctor about the clinic and said I would probably be able to stop having insulin injections, he said he would eat his hat if that ever happened. He never has, even though I have given him several serving suggestions! "
Another doctor also claiming dramatic success using diet to treat diabetes is Dr Neal Barnard, an American expert whose book, Reversing Diabetes, just published in the UK. " We've run trials showing that a diet with zero animal fats can control blood sugar three times more effectively than the diet recommended by the American Diabetes Association," he says. He claims his zero fat approach makes the body more responsive to insulin, allowing patients to cut down their drugs or stop using them entirely.
The charity Diabetes UK makes the same criticism of both approaches. "The crux of all these diets is losing weight," says a spokesman. "If you do that, you make insulin work more effectively, and that may mean you can stop taking it. But that doesn't mean you are cured. Diabetes is a disorder people have for life. When people stop these diets - which they often do because sticking to them is hard - they will have to go back on the drugs." The charity recommends a "healthy, balanced diet".
"If you are on a non-conventional diet, the important thing is to be carefully monitored," says David Haslam. “ It is vital your blood sugar levels aren't allowed to get above the healthy level, because we know that the damage to the blood vessels that follows can happen quickly. But if you can keep a healthy level with diet, go for it. A low GL diet for diabetes obviously makes sense."
David Haslam is in favour of using drugs to control blood sugar if other means aren't working. But the drugs aren't risk-free either. Earlier this month, doubts were raised about the safety of one of the leading drugs, Avandia, after a report in the New England Journal of Medicine suggested it raised the risk of heart problems by 40 per cent. All the experts agree there is a need for more research. The difficulty is that funding for dietary approaches is tiny compared to money spent on testing drugs.
