The chocolate will have a lower GI because it is high in fats..just because it has a low GI does not necessarily mean its a great food to be eating. Avoid anything processed and that high in sugars to begin with and just eat natural!
Actually Sarge, everything lowers GI, even other sugars!
Pure glucose's numbers drop when you add maltodextrin, OR proteins, OR fats, or SALT, OR Water, OR Cellulose fiber.... anything the mucks up the absorbtion rate lowers GI...