The research on periodic fasting has identified a biological process in the body that converts bad cholesterol in fat cells to energy, thus combating diabetes risk factors.
Researchers at the Intermountain Heart Institute at Intermountain Medical Center in Murray, Utah, noticed that after 10 to 12 hours of fasting, the body starts scavenging for other sources of energy throughout the body to sustain itself.
The body pulls LDL (bad) cholesterol from the fat cells and uses it as energy.
"Fasting has the potential to become an important diabetes intervention," said Benjamin Horne, director of cardiovascular and genetic epidemiology at the Intermountain Medical Center Heart Institute and lead researcher on the study.
"Though we've studied fasting and it's health benefits for years, we didn't know why fasting could provide the health benefits we observed related to the risk of diabetes," Horne said.
Prediabetes means the amount of glucose, also called sugar, in the blood is higher than normal but not high enough to be called diabetes.
Prior research done by Horne and his team in 2011 focused on healthy people during one day of fasting and showed that routine, water-only fasting was associated with lower glucose levels and weight loss.
"When we studied the effects of fasting in apparently healthy people, cholesterol levels increased during the one-time 24-hour fast," said Horne.
"The changes that were most interesting or unexpected were all related to metabolic health and diabetes risk.
"Together with our prior studies that showed decades of routine fasting was associated with a lower risk of diabetes and coronary artery disease, this led us to think that fasting is most impactful for reducing the risk of diabetes and related metabolic problems," Horne said.
Horne launched the new study to look at the effects of fasting in prediabetics over an extended period of time. The study participants were prediabetics, including men and women between the ages of 30 and 69 with a least three metabolic risk factors.
These risk factors include a large waistline, a high triglyceride level, a low HDL or "good" cholesterol level, high blood pressure and high fasting blood sugar.
"During actual fasting days, cholesterol went up slightly in this study, as it did in our prior study of healthy people, but we did notice that over a six-week period cholesterol levels decreased by about 12 per cent in addition to the weight loss," said Horne.
"Because we expect that the cholesterol was used for energy during the fasting episodes and likely came from fat cells, this leads us to believe fasting may be an effective diabetes intervention," Horne said.