, it is of interest to know whether addition of a small dose of acarbose to rapidly digestible starch can change the digestive profile to that of a slowly digestible starch. If this is achieved, one would expect with acarbose a lower influx rate of starch-derived glucose in the early postprandial period and a higher influx rate in the late postprandial period, resulting in approximately the same bioavailability of glucose as without acarbose. However, in our study we found that a low dose of
12.5 mg of acarbose added to rapidly digestible corn pasta significantly reduced the rate of appearance of exogenous glucose in the first 4 h after ingestion, whereas in the postprandial period between 4 and 6 h the RaEx was the same. Consequently, the bioavailability of starch during the 6-h test period was reduced by 22%. In addition, the percentage of the ingested dose that was excreted as 13CO2 during the study period was significantly reduced by acarbose (CP 37.5 ± 2.8 %dose; CPac 27.2 ± 2.2 %dose; P = 0.004). Similar data were found by Achour et al.  comparing digestible and partially indigestible cornstarch: the percentage of the ingested dose excreted after ingestion of digestible starch was 35.3 ± 3.0 and that after partially indigestible starch 28.2 ± 1.8 over a period of 8 h.