Patients who consumed only 600 calories a day for two months were able to reverse their Type 2 diabetes, according to a groundbreaking British study. The research, involving just 11 patients, suggests a very low-calorie diet can remove fat that clogs the pancreas, allowing normal insulin secretion to be restored, according to Newcastle University.

Seven of the 11 patients remained free of diabetes three months after the study, researchers said.

Type 2 diabetes, also known as adult-onset diabetes, has been thought to be a progressive, irreversible condition. Once diagnosed, some patients can control their diabetes with tablets, but many eventually require insulin injections.

Type 2 diabetes occurs when the pancreas is unable to produce sufficient insulin to regulate fat metabolism and sugars in the blood, or when the body is unable to react to the insulin. It’s different than Type 1, or juvenile diabetes, an autoimmune disorder in which the immune system destroys the beta cells that produce insulin.

The study was announced Friday at an American Diabetes Association conference, according to Newcastle University. It is being published in the journal Diabetologia.

The study enrolled 11 patients who had developed Type 2 diabetes later in life, and restricted them to a super-low-calorie diet consisting of diet drinks and non-starchy vegetables. Over eight weeks, researchers monitored the fat content in the liver and the insulin production from the pancreas, comparing the results to a control group of non-diabetics.