BACKGROUND: Foods with a low glycemic index are increasingly being acknowledged 
as beneficial in relation to the insulin resistance syndrome. Certain organic 
acids can lower the glycemic index of bread products. However, the possible 
effect of acids in fermented milk products on the glycemic index and on 
insulinemic characteristics has not been addressed. The metabolic effects of 
fermented milk or pickled products used as additives to mixed meals have also 
not been addressed.
OBJECTIVES: One objective was to characterize the glycemic and insulinemic 
responses after intake of regular or fermented milk products (study 1). In 
addition, the acute metabolic effect of fermented milk (yogurt) and pickled 
cucumber as supplements to a traditional breakfast based on a high-glycemic 
index bread was evaluated (study 2).
DESIGN: Ten healthy volunteers were served different breakfast meals after an 
overnight fast. Capillary blood samples were collected before and during 2 
(study 1) or 3 (study 2) h after the meal. White-wheat bread was used as a 
reference meal in both studies.
RESULTS: The lactic acid in the fermented milk products did not lower the 
glycemic and insulinemic indexes. Despite low glycemic indexes of 15-30, all of 
the milk products produced high insulinemic indexes of 90-98, which were not 
significantly different from the insulinemic index of the reference bread. 
Addition of fermented milk (yogurt) and pickled cucumber to a breakfast with a 
high-glycemic index bread significantly lowered postprandial glycemia and 
insulinemia compared with the reference meal. In contrast, addition of regular 
milk and fresh cucumber had no favorable effect on the metabolic responses.
CONCLUSIONS: Milk products appear insulinotropic as judged from 3-fold to 6-fold 
higher insulinemic indexes than expected from the corresponding glycemic 
indexes. The presence of organic acids may counteract the insulinotropic effect 
of milk in mixed meals.