Glutinous rice reportedly originated in Northern Thailand, and several hill tribes, including the Karen, Mon, and Hmong, live in this area. A comparison of the rice cake-eating culture among the Karen, Lahu, Akha and Lisu tribes was made by collecting data from field surveys conducted six times during 2005-2009. Rice cakes made by pounding rice in a mortar were found with all these tribes when celebrating at their religious ceremonies on their New Year's Day and Christmas. These rice cakes were also presented to temples and churches. With the exception of the Karen, rice was pounded with a mortar and pestle. Kneaded rice cakes were also made by the Lisu and Aka tribes. The Lisu make them communally in the village on Thanksgiving Day, while the Akha usually make them at home. The Karen wrap the rice cakes in bamboo leaves and eat for good health. The Karen, Lafu and Akha tribes add perilla seeds to steamed rice when pounding the rice, while the Lisu add black sesame. This helps to prevent the rice cakes from sticking to the mortar and pestle, and imparts a more sweet-scented and better taste.