Effects of dark chocolate on appetite variables and glucose tolerance: a 4 week randomised crossover intervention in healthy middle aged subjects

Cocoa is a well acknowledged polyphenol-rich functional product. However, the mechanisms and effects of cocoa products on glucose metabolism and appetite regulation are not clear. A crossover randomised study was carried out in twenty (4male; 16female) healthy middle-age (62.6 ± 6.5 yr) subjects with normal BMI (23.0 ± 2.0 kg/m 2). Effects on postprandial glucose-, insulin- and subjective appetite responses to a preload (30 min) of 70% dark-chocolate (DC), with and without a preceding 4-week DC intervention, were evaluated. SCFA (acetate, propionate and butyrate), BDNF, GLP-1, and PYY were determined in plasma at fasting. An isocaloric white-chocolate-like product (CP) was included as a control. DC increased (main effects; p < 0.05) glucose- and insulin responses in comparison with CP. Postprandial hunger sensations were reduced (p < 0.05), whereas acetate and propionate were higher (p < 0.05) after 4-week DC intervention. The results suggest that cocoa may play a role in appetite regulation, however the unexpected increase in postprandial glucose- and insulin concentrations requires further investigation.