Grapefruit Juice For Help In Lowering Blood Glucose Levels

Grapefruit been known to boost weight-loss since the 1930s, with studies showing it contains a fat-burning enzyme that helps drinkers to shed pounds. But a new study by researchers at the University of California-Berkeley claims it can also combat diabetes by lowering blood glucose levels and improving insulin tolerance.

The study, which involved experiments on laboratory mice, found those fed a high-fat diet that also drank grapefruit juice gained 18 percent less weight than those on a high-fat and water diet. As well as greater weight loss, the grapefruit-drinking mice also had a 13-17 percent reduction in blood glucose levels and a three-fold reduction in insulin levels, Medical News Today reports.

Lead researchers Joseph Napoli and Andreas Stahl, both of the Department of Nutritional Sciences and Toxicology, noted few studies have examined the effects of grapefruit juice on metabolism. But their findings, published in the Public Library of Science journal PLOS ONE, suggest the juice may help control blood sugar as effectively as some diabetes medications.
 

For the study, the researchers tested the effects of clarified, pulp-free grapefruit juice diluted with water at different concentrations on five groups of mice fed either a high- or low-fat diet for 100 days. The grapefruit juice was sweetened with saccharin to make it less bitter. These effects were compared with another group mice, which were fed a high-fat diet but were given water to replace grapefruit juice.
 

The team also tested the effects of a compound found in grapefruit juice — naringin — on some mice fed a high-fat diet. A second group of mice fed a high-fat diet were given metformin — a drug used for lowering glucose levels in people with type 2 diabetes.

The results showed grapefruit juice had no effect on weight for mice fed a low-fat diet, although these mice did show a two-fold reduction in insulin levels. What’s more, the researchers found that naringin lowered blood glucose levels in the mice just as much as metformin.
 

"That means a natural fruit drink lowered glucose levels as effectively as a prescription drug," said Napoli.