[4] The Jahai people believe in a religious system with Karei (pronounced "Karεy") as a supernatural force that oversees their actions and behaviours.

[5] Therefore this led to a rich odor lexicon in the Jahai language,[5] a trait also shared among the Maniq people in Thailand.

[6] The Jahai people, who are traditionally nomadic, live in permanent settlements in parts of the Royal Belum State Park as part of the tourist attraction.

They lived in isolation, and most likely lacking of infrastructure such as roads, schools, health services, and so on.

The mortality rate of the Jahai people in villages along the Kejar River was as high as 50% in children due to serawan, a mystery illness which caused the population there to dwindle from 600 to 400.