Losing a relatively small amount of weight and increasing exercise can put the brakes on the progression of prediabetes into full-blown Type 2 diabetes. People with prediabetes have blood sugar or glucose levels that rise above normal but that have not climbed high enough to qualify as diabetes.

Shedding as little as 5 percent to 7 percent of body weight can help stop the disease in its tracks. That means someone who weighs 200 pound would have to lose between 10 and 14 pounds. “I stress to my patients that we’re not talking about a huge amount of weight,” said Dr. Rhonda Bentley-Lewis, an assistant professor of medicine at Harvard Medical School.

Lifestyle changes proved important for thousands of people suffering from prediabetes who took part in the Diabetes Prevention Program. Losing a little weight, cutting fat and calories out of their diets and increasing physical activity helped 58 percent of study participants prevent progression of their prediabetes.

That finding is significant for people who would rather try to control the disease with diet and exercise, and most patients prefer that strategy over medication, said Dr. Bentley-Lewis.

A recent English study indicated a radical diet change can even reverse diabetes in some people. When 30 people who had lived with Type 2 diabetes for up to 23 years undertook an eight-week low-calorie-milkshake diet, almost half experienced a remission that lasted six months after they completed the stringent diet and returned to normal eating.

The small English clinical trial offers hope to millions who are living with Type 2 diabetes. Many experts have believed the intractable disease is incurable and only grows worse over time.

“This is a radical change in our understanding of type 2 diabetes,” said Dr. Roy Taylor, a professor at Newcastle University in England and the study’s senior author. “If we can get across the message that ‘Yes, this is a reversible disease—that you will have no more diabetes medications, no more sitting in doctors’ rooms, no more excess health charges—that is enormously motivating.”

Doctors usually diagnose prediabetes by performing one of three tests. Two of the tests require fasting, while the third does not. That test, the A1C, measures average blood glucose levels over two to three months.

Read more on the three tests for prediabetes at How Much Weight Do I Have to Lose to Prevent Diabetes?