Plants with hypoglycemic activity in humans.

More than 400 plants with suspected glucose-lowering potential are known. In most cases, the evidence for this action is based purely on animal experiments or traditional use. This, however, provides only limited information about its clinical usefullness. Therefore this paper reviews direct evidence from clinical trials. A systematic literature search identified 22 such papers. The majority reported positive effects. However, much of the data are of poor methodological quality. Only five randomised controlled trials were found, and even these do not convincingly demonstrate the usefulness of the remedies in question. It is concluded that the use of hypoglycemic plant remedies is not supported by results from rigorous clinical trials and requires further investigation.