Bitter foods include lettuce, lettuce, fennel, celery, bitter gourd, coriander, moss and so on. Dried and fresh fruits include almonds, black dates, peach kernels, mint leaves and tea leaves. Among cereals and beans, there are glutinous rice, fermented soybean, buckwheat and so on.

Source.

Lettuce is native to the Mediterranean coast of Europe and domesticated from wild varieties. The ancient Greeks and Romans ate it first.

Lettuce has been introduced into China for a long time, and it is widely planted in the southeast coast, especially in the suburbs of big cities and Guangdong and Guangxi. In recent years, the planting area has expanded rapidly, and lettuce has also entered the dining table of ordinary people from hotels and restaurants.