Tropical leaf extracts may boost pre-diabetic health measures: Clinical trial
Eight weeks of supplementation with leaf extracts from the botanicals were associated with improvements in blood glucose levels for Elaeis guineensis and blood lipid levels for Ficus deltoidea, according to findings published in Nutrition Journal.
African oil palm (Elaeis guineensis) is said to equal soybeans as a source of human vegetable oil consumption. The mistletoe fig (Ficus deltoidea) has traditionally been taken in Malaysia as tea.
Extracts from the leaves of both botanicals have been reported to be rich in phenolic compounds with potential hypoglycemic effects. The study was funded by Biotropics Malaysia, which also provided the extracts used in the study.
Lead author Douglas Kalman PhD, RD, Director, Nutrition & Applied Clinical Trials at Miami Research Associates, told NutraIngredients-USA that the study’s findings have “interesting implications”.
“These botanicals have prior data for having pharmacologic and physiologic activity as related to blood sugar control,” he explained. “Early pre-clinical work demonstrated an incretin effect. This study was the first human clinical trial in a population at risk for diabetes (meeting the definition of pre-diabetic).
“We were pleasantly surprised to observe an effect of the E Guineensis for glucose and insulin effects (lowering) as well as the F Deltoidea for reducing lipids. Hallmarks of metabolic syndrome include abnormal blood sugar control and elevated blood lipids.
“These two botanicals seemed to have interesting and clinically relevant effects for improving the health of pre-diabetics. Most certainly both botanical agents are deserving of further research,” added Dr Kalman.
As many as 79 million American adults are pre-diabetic, with many of them classed as overweight or obese, according to estimates from the US Centers for Disease Control and Prevention (CDC). This puts them at three times higher risk for developing type-2 diabetes than normal weight people.
Dr Kalman and his co-workers recruited 30 otherwise healthy adults with pre-diabetes with an average age of 45.6 and an average BMI of 32.1 kg/m2. Participants were randomly assigned to one of three groups: The first two groups received 500 or 1,000 milligrams per day of E. guineensis leaf extract, respectively, while the third group received 1,000 mg or F. deltoidea leaf extract for eight weeks.
Results showed that E. guineensis was associated with decreases in fasting plasma glucose and insulin levels, insulin resistance, and increases in insulin sensitivity.
On the other hand, F. deltoidea leaf extract was associated with significant reductions in total and LDL cholesterol concentrations, but no changes in glycemia variables, said the researchers.
Dr Kalman and his co-workers reported that they did not observed any serious adverse events during the study.
Commenting on the observations, the researchers noted that E. guineensis is rich in catechins and polyphenols, and earlier studies had indicated an effect in lab animals with diabetes.
“This suggests a potential benefit for the pre-diabetic and diabetic states,” they said.
The results for F. deltoidea, however, disagreed with earlier animal studies, which had indicated a glucose lowering effect.
“This study did, however, demonstrate a lipid lowering effect of great clinical interest,” wrote Dr Kalman and his co-workers.
“The decreases in total cholesterol and LDL observed are of statistical and clinical significance and are worthy of further exploration.”
Source: Nutrition Journal
“Efficacy and safety of Elaeis guineensis and Ficus deltoidea leaf extracts in adults with pre-diabetes”
Authors: D.S Kalman, H.I. Schwartz, S. Feldman, D.R. Krieger