Ginger is possibly one of the earliest trade commodities. It was transplanted along with the earliest human migrations from Asia and served as a key element in spice trade-based colonial expansions from Europe. In fact, the demand for ginger was so great that it was made extinct in the wild as early as two thousand years ago. It features prominently in all the main traditional medicine systems of the world. In these systems, it was universally seen as an antidote to the effects of cold, especially as it affects the digestive and respiratory systems. Ginger is a well-known modern folk remedy for upset stomach and motion sickness, and there is clinical evidence that it may be effective against motion sickness and other causes of nausea and vomiting. Modern clinical trials have confirmed several key features of the plant's traditional reputation, and laboratory studies suggest that clinical research will eventually reinforce other traditional applications. Among effects on circulatory functions demonstrated in laboratory studies, ginger appears to have antiplatelet ("blood thinning") effects; however these effects have have been refuted in more recent clinical studies, so although there is one case study indicating interaction with phenprocoumon, theoretical concerns that ginger might increase the effects of other blood thinners are now less well supported. Laboratory studies indicate that ginger may also increase the bioavailability of many other medications. So strong has been its reputation and so clear its effects on consumption that in some of its prospect grades it merits high ratings even where it has almost no clinical trial data.