The Newcastle team noted that, typically, the function of insulin-producing beta cells declines with time, such that more than half of people with Type 2 diabetes require insulin therapy after 10 years. However, they conducted a study to find out how a low-calorie diet would impact beta cell failure and insulin resistance.
The study involved 11 people with Type 2 diabetes, who were tested after one, four and eight weeks on a 600-calorie a day diet. After just one week, fasting plasma glucose and hepatic insulin sensitivity normalized, while fat in the liver decreased by 30%. Over the eight-week period, beta cell function increased toward normal and fat in the pancreas decreased. In short, the researchers explained:
"Normalization of both beta cell function and hepatic insulin sensitivity in type 2 diabetes was achieved by dietary energy restriction alone. This was associated with decreased pancreatic and liver triacylglycerol stores. The abnormalities underlying type 2 diabetes are reversible by reducing dietary energy intake."
Beta cells, meanwhile, are also capable of regeneration. Gamma aminobutyric acid (GABA), an amino acid, has both protective and regenerative effects on islet beta cells, such that it may even reverse diabetes.
Black cumin (Nigella sativa L.) is another compound that has led to partial regeneration of beta cells in animal studies, while the following may also be helpful: vitamin D, curcumin, arginine, bitter melon, avocado seed extract, chard extract.