People with type 2 diabetes are just as likely to lose weight and control their blood glucose levels if they follow a 5:2 diet than an ongoing daily calorie-restricted diet, according to a world-first study by University of South Australia researchers.

In a paper published in JAMA, lead author UniSA PhD student Sharayah Carter says intermittent fasting could be a solution for people with diabetes who find it difficult to stick to a diet 7 days a week.

Her findings are based on a year-long clinical trial of 137 people with type 2 diabetes, half of whom followed a 5:2 diet and the others an ongoing restricted diet, consuming between 1,200 and 1,500 calories a day.

The study is the first long-term clinical trial comparing the different diets of people with type 2 diabetes.

Fasting on two non-consecutive days, consuming between 500-600 calories, and then eating normally for five other days each week not only results in weight loss but also improved blood glucose control.

While fasting is safe for people with diet-controlled type 2 diabetes, for those using insulin and other oral medications likely to cause hypoglycaemia, blood glucose levels need to be monitored and medication doses changed accordingly, the study authors caution.

Sharayah’s co-supervisor, UniSA Professor of Nutrition Peter Clifton, says health-care costs relating to diabetes are increasing, costing the world around US$673 billion each year and $14.6 billion per year in Australia alone.

“It is the 21st century’s health epidemic and the biggest challenge confronting Australia’s health system,” Professor Clifton says.

“Conventional weight loss diets with daily energy restrictions are difficult for people to adhere to so we must look for alternative solutions.”