"Lo Lo Den" Tribe woman with red lips caused by chewing Areca nut (also called Betelnut or Betel Quids) (Bảo Lạc, Vietnam)
The Areca nut is wrapped with "lá trầu" leaf (Betel leaf) and chewed for its exhilarating lift. Betel chewing has been claimed to produce a sense of well-being, euphoria, heightened alertness, sweating, salivation, a hot sensation in the body and increased capacity to work.
Just like alcohol, tobacco, coffee and sakau, Areca nut and Betel leaf are culturally-approved psychoactive drugs.
The Areca nut, by association, is sometimes inaccurately called the "Betel nut".
See the Areca nut Wikipedia page.
For more information about the "Lo Lo Den" Tribe, please check the album description.