The Spanish-based researchers at CIBERDEM, the Instituto de Ciencia y Tecnología de Alimentos y Nutrición, and the Universidad Complutense de Madrid had previously shown the anti-diabetic potential of cocoa flavanols in vitro. Fernández-Millán et al’s latest study, due for publication in Molecular Nutrition & Food Research, used a live animal model.
“These findings provide the first in vivo evidence that a cocoa-rich diet may delay the loss of functional beta cell mass and delay the progression of diabetes by preventing oxidative stress and beta-cell apoptosis,” they said.
Rats fed cocoa powder
Pre-diabetic obese rats were fed a control diet or 10% cocoa-rich diet for six to 15 weeks. The cocoa came from 100 g/Kg of Natural Forastero cocoa powder, provided by Nutrexpa.
After the trial period, the researchers conducted a glucose tolerance test (GTT) and assessed beta cell mass, beta cell apoptosis and markers of apoptosis and oxidative stress.
They found that cocoa feeding rats demonstrated improved factors associated with type 2 diabetes such as attenuated hyperglycaemia, reduced insulin resistant and increased beta cell mass compared to the control group.
Reduced body weight
Although there was no difference in food intakes, they also found that the cocoa group had 20% less body weight than the control group.
“This effect has been attributed to the ability of cocoa polyphenols to regulate lipid metabolism and prevent visceral fat deposition,” said the study.
The researchers said their findings were consistent with earlier research by Fu et al that found dietary supplementation with the flavanol epicatechin preserved functional beta cell mass in non-obese diabetic mice.
Molecular Nutrition & Food Research (online ahead of publication)
‘Cocoa-rich diet attenuates beta cell mass loss and function in young Zucker diabetic fatty rats by preventing oxidative stress and beta cell apoptosis’
Authors: Elisa Fernández-Millán, Isabel Cordero-Herrera, Sonia Ramos, Fernando Escriva, Carmen Alvarez, Luis Goya and María Angeles Martín