Drinking less alcohol, eating more vegetables and exercising can prevent or delay the onset of diabetes, researchers said on Friday in a study showing that lifestyle changes can make a big difference.

Diet and exercise reduced the incidence of diabetes by about 43 percent over 20 years among 577 high-risk Chinese adults, the researchers reported in the journal Lancet.

At the end of the 20 years, 80 percent of those who changed what they ate and exercised more had diabetes, compared with 93 percent who made no changes, said Guangwei Li of the China-Japan Friendship Hospital in Beijing and Ping Zhang at the U.S. Centres for Disease Control and Prevention.

The findings came as part of a series of studies addressing new research about diabetes, which affects 246 million adults worldwide, and accounts for 6 percent of all global deaths.

"The challenge is to translate research findings into substantial clinical improvements for patients. Although prospects are hopeful, they are not assured," the Lancet wrote in a commentary.

Type 2 diabetes accounts for about 90 percent of all diabetes cases and is closely linked to obesity and physical inactivity. Type 1 diabetes is an auto-immune disease often diagnosed at an early age.

The International Diabetes Federation estimates more than 380 million people will have a form of diabetes by 2025 as more developing nations adopt a Western lifestyle.

The researchers followed 577 Chinese adults at risk of diabetes over a 20-year period to see how prodding people to change their lifestyles could affect their health.

The volunteers were assigned to either a control group or one of three groups that included an improved diet, better exercise or a combination of both.

The researchers did not say what specific foods or amount of exercise contributed to the health improvements but said the findings provide an effective strategy to deal with a disease that kills about 3 million people worldwide each year.

"This study has shown that ... group-based interventions targeting lifestyle changes such as diet and exercise produce a durable and long-lasting reduction in incidence of type 2 diabetes," the researchers wrote.

Another team reported that insulin infusions or multiple daily injections given early to people with newly diagnosed type 2 diabetes helped the body's insulin-producing cells and restored blood sugar control faster than standard pills.

Too much glucose, or blood sugar, in the blood - a hallmark of diabetes - can damage the eyes and kidneys, and also leads to heart disease, stroke and limb amputations.