The bean extract – marketed under name Beanblock – was also associated with a suppression of levels of the hunger hormone, ghrelin, while levels in the placebo group rebounded several hours after the meal.
“Although these findings are preliminary and limited by the small experimental sample, they encourage further studies to test the effects of [the bean extract] supplemented in acute and chronic administration to obese, glucose-intolerant and diabetic subjects in order to evaluate the applicability and potential advantages of this product in these kinds of patients,” wrote the researchers in the British Journal of Nutrition.
The randomized, double-blind, placebo-controlled study was performed by researchers from the Universita degli Studi di Milano and Indena S.p.A. The Italian botanical extract supplier also funded the study.
The ingredient seems well placed from a market-size perspective. A study released recently stated that currently, more than 25 million Americans suffer from type 2 diabetes. It goes on to state that if the obesity epidemic continues unchecked, the number of new cases of type 2 diabetes, coronary heart disease and stroke, hypertension and arthritis could increase 10 times between 2010 and 2020—and double again by 2030.
The researchers recruited 12 healthy people aged between 20 and 26 to participate in their study. The BMI of the volunteers ranged from 19.7 to 23.5 kg/m2. Participants were randomly assigned to receive either a tablet containing Beanblock (100 mg) or placebo just before consuming a test meal.
Results showed that the bean extract was associated with lower increases in glucose and insulin 30 minutes after the meal, compared with the placebo, with rises of 15.4% in the bean group, compared with 26.1% in placebo group.
In addition, the bean extract was associated with a lower desire to eat over the course of three years than placebo. Ghrelin levels decreased similarly in both groups, said the researchers, but a rebound in levels was observed in the placebo group, while no such increase was seen in the bean group.
“These results support that further studies are needed to prove the concept of employing [the bean extract] as a supplement in mixed balanced meals in obese, glucose-intolerant and diabetic subjects,” they said.
Source: British Journal of Nutrition
Published online ahead of print, doi: 10.1017/S0007114512003741
“Phaseolus vulgaris extract affects glycometabolic and appetite control in healthy human subjects”
Authors: A. Spadafranca, S. Rinelli, A. Riva, P. Morazzoni, P. Magni, S. Bertoli, A. Battezzati